text:
Innovations of Organic Agriculture, Challenges and Organic Certification in the United States

Organic agriculture is a production system that maintains the health of an agro-ecosystem by enhancing biodiversity and producing healthy soils by eliminating the use of chemicals. Other practices are used to enhance properties of the soil and increase long term soil fertility and prevent pest and diseases. Globally, organic agriculture has grown approximately by 20% yearly as consumers and growers make healthier food choices and show more concern about the impacts of our actions on the environment. Organic agriculture attempts to increase the level of food security and create a more sustainable environment for future generations. Organic certification has continuously increased as the benefits steady arise for farmers looking to produce healthier food. This article will observe the history, present day, challenges, certifications, impacts and benefits of the intriguing organic agricultural world.

Introduction
Organic agriculture"s origin can be traced back to the early years of the twentieth century. Europe and the United States are perceived as the original pioneers with rich roots of organic agriculture that changed the view on agriculture, nutrition and food. Many farmers, scientists and consumers perceived organic farming as a paradigm shift in agriculture (Wynen, 1996). The pioneers of the early organic movement were inspired by a need to overturn the constant dilemmas of agriculture -erosion, soil depletion, decline of biodiversity, low quality food and livestock feed, and rural poverty. They welcomed a concept that the long-term effects of soil damage or health affects the overall health of a nation that is primarily focused on agriculture. The soil"s health and vitality were believed to be embodied in its biology and in the organic soil fraction called humus (Heckman, 2006).
Over the previous few decades there has been an eventful change in the idea, movement and industry of organic agriculture. Around the early 1970s in the United States, a gathering of industrial growers and farmers began practicing organic farming, which at that time was a little-known and uncommon agricultural practice. They wanted to intervene into this new practice because they were convinced that there was something wrong with the commercial food model on a large production scale. During this time, majority of society was unaware of the new termed word "organic". Many were accustomed to conventional production, so it was very rare for consumers to shop organic food. Not only was the unawareness in society was high but a few scholars and scientists were frowned upon and disregarded for there interests in pursuing organic research. The United States government and federal scientists did not acknowledge the fresh practices of organic farming. The growth of organic agriculture has flourished into a multi-billion-dollar industry over the last four decades. Presently, there are isolated organic food sections located in various food supermarkets established all over the United States. According to Crowder and Reganold (Crowder and Reganold, 2015), seventy-five five percent of US consumers report buying organic products. Certified organic agricultural production area in the United States has increased steadily since the inception of the 1990 Organic Foods Production Act. Advantages of organic agriculture include economic benefits for producers. directly towards organic agriculture. Furthermore, the federal government has completely adapted this practice because not only do they receive organic farming, but they have created federal standards that must be followed in order to be certified organic. The approval of organic production methods now produces foods that carry the official USDA seal. On several counts, the organic movement has been incredibly successful, arguably among the most effective movements of the late twentieth century (Obach, 2015).

Principles of Organic Agriculture
Organic agriculture is production system that evades the use of synthetic pesticides and fertilizers, relies on biological pest control, and relies on crop rotation, green manure, compost, and other recycled wastes to maintain soil fertility (Goh, 2011). Improving the overall health of an agricultural ecosystem including the populations of plants, animals, soils, and humans is the ultimate objective of organic agriculture. Organic agriculture is based on certain principles as stated by Lynch (2009): • Protect the environment, minimize soil degradation and erosion, decrease pollution, and optimize biological activity and health, • Maintain soil fertility by optimizing conditions for biological activity within the soil, • Maintain biological diversity within the system, • Recycle materials and resources to the greatest extent possible within the enterprise, and • Rely on renewable resources in locally produced organic food systems.

Organic Agriculture and the Environment
Soil degradation is a significant issue that continues to challenge organic agriculture. Tilling is a practice that is commonly used in many of the developed countries. It has many purposes but the main purpose for weed management and introducing and managing organic amendments (Barberi, 2006). Raviv (2010) reported that the most important field of research in organic horticulture should be the identification of novel and efficient methods for weed control that have no negative effects on system sustainability, especially on soil quality parameters such as soil humidity, soil pH, soil microbial activity, soil water holding capacity, etc. Raviv (2010) also believed that boosting tillage could balance the improved energy efficiency in an organic farming system. Agriculture has the capability to alter nature"s characteristics such as soil, water, air, flora, and topography. Environmental injury arises from agricultural mistakes like mishandling of pesticides and fertilizers, grouping large numbers of livestock in a small area, over tilling, and repetitive crop rotations. These issues can lead to soil degradation and desertification. Consequently, energy efficient strategies to control weeds need to be further developed, including no-till and reduced tillage cropping systems. However, if managed correctly, all of these negatives can reverse into positive impacts by diversifying the landscape and increasing biodiversity (Scherr and McNeely, 2008;Rahmann, 2011). Here, organic agriculture can play a significant role, much more progressive than conventional farming. Conventional farming requires a lot of enforcing and overlooking of agricultural practices, primarily with pesticides and fertilizers. Organic agriculture diminishes the threats of misuse of pesticides considerably. Also, by using organic and natural fertilizers, there is limited risks of fertilizer pollution. Animals and plants are relying on the environment, so it is imperative that agricultural events do not bring any neglect or harm but instead enhance the natural environment.

Challenges of Organic Agriculture
Major challenges in organic crop production are as follows:

Crop Yield
Over the years, one of the primary challenges of an organic farming system has been conventional farming production consistently outperforming the organic production system. Past studies have shown a consistent disparity between organic and conventional yields due to meta analyses performed. Not long ago, a meta analyses report concluded an average lower yield in organic systems from 19% to 25% across numerous crops (De Ponti et al., 2012;Ponisio et al., 2015;Seufert et al., 2012). A consistent lower yield in organic production could create hesitation of converting to organic because critics of organic agriculture can argue there is no rational reason to convert to organic if the yields are lower. With a growing population, critics can contend that conventional farming is more efficient with nearly 30% less land. Therefore, the unfarmed land can be used for environmental benefits and conservation (Baier, 2000;Asafu-Adjaye et al., 2015;Phalan et al. 2011;Trewavas, 2001). However, yield gains have not been plainly associated with increased land set aside for conservation at the global or regional scale, thus the yield/conservation tradeoff is likely a false narrative that does not accurately represent the complexity of an agricultural system (Kremen, 2015).

Pest Management
Integrated pest management (IPM) is one of the earliest large-scale promoted Sustainable Agricultural Practices (SAPs). According to (FAO, 2020), IPM "means the careful consideration of all available pest control techniques and subsequent integration of appropriate measures that discourage the development of pest populations and keep pesticides and other interventions to levels that are economically justified and reduce or minimize risks to human health and the environment." The use of cultural, mechanical, physical, and biological controls is preferred in organic IPM, instead of using chemical pesticides. Due to the growth of organic farming, many countries are adapting to this method not only economic benefits but also for sustainable crop production. Organic pesticides are a growing trend in the US. However, they do have several contrasts when compared to conventional pesticides. Some of the shortcomings are the lack of systemic activity, brief shelf life, generally only effective on immature insects, most require ingestion to be effective and can be costly.

Disease Management
Environmental and toxicity issues have surfaced due largely to mishandling and abusive use of many synthetic fungicides (Singh Gurjar et al., 2012). A growing consciousness about environmental contamination due to pesticides, human health and development of fungicide-resistant strains in plant pathogens has confronted the plant pathologists to pursue eco-friendly non-toxic organic compounds for replacing the suggested fungicides in recent years (Meena et al., 2013). Scientists have found out that countless compounds obtained from living organisms have discovered a use in crop protection. Organic agriculture only allows a few "natural" compounds for managing pests and diseases such as copper which is applied as fungicide in apple, grape, potato, and tomato production. In the organic production of crops such as apple, grape, tomato, and potato, which are susceptible to severe fungal infections, copper is often used as one of the very few "natural" fungicides permitted in organic agriculture. But as a heavy metal, copper is under debate in the organic sector (Nuijten et al., 2018). Being that it is under investigation, introducing resistant varieties has become the prominent lead strategy to replace copper.
The European project CO-FREE aimed to develop innovative methods, tools, and concepts for the replacement of copper to reduce the use of copper in organic farming systems, as it is considered harmful for the environment (Dagostin et al., 2011). According to Dagostin et al., it is shown that it is not easy to minimize copper use by replacement with alternative plant protection products, as they are often less effective than copper-based sprayings itself, causing a major negative economic impact in most production systems (De Wit, 2016). However, previous studies have shown that when new varieties are introduced to society, they often run into sizeable obstacles. These obstacles arise because of the lack of awareness of the new varieties from retailers and consumers, which is needed to open and sustain a market (Tamm et al., 2004;Speiser et al., 2013;Vanloqueren and Baret, 2008). For producers, disease resistance is an imperative trait needed. However, consumers, traders, and retailers are not as concerned as farmers due to the lack of knowledge that current varieties are not always robust. The reason disease management has never been a concern for consumers is because, through the use and availability of chemical pesticides, many demands were still met (Vanloqueren and Baret, 2008).

Organic Vertical Gardening
Vertical gardening refers to any kind of construction and support structure for growing plants in an upwards direction effectively. When plants are grown vertically, it increases the options for garden creativity and production. Vertical gardening is an efficient way to utilize limited space. As more buildings go up, the availability of land decreases which can create a problem in the agricultural world. Vertical gardening can help neutralize this issue by maximizing the use of the limited space. There are 2 major categories that vertical gardens can be split into: green facades and living wall systems (Natarajan et al., 2015). Green facade is a vertical system that includes plants that climb up tall surfaces or objects once they are planted into the soil at the base of a wall. Not only will the plants use the wall for vertical support but can use other structures attached to the wall such as a trellis or cable. Living wall systems are containers, panels or planters that contain soil or medium for plants to grow in, that are attached along a wall (Natarajan et al., 2015). Vertical gardening has many advantages. From a maintenance standpoint, the advantages could include reducing disease problems by being elevated from the ground surface, by increasing the air circulation through the foliage, and also making it easy to detect pests. Plus, growing crops vertically makes harvesting much easier because the plants are eye level and easier to reach versus bending over numerous times for crops that are traditionally planted in the soil. There is no definite, set structure to create a vertical gardening system and this allows for creativity when designing. These systems can be made from fences, cages, ladders, hanging baskets, and many other types of structures.

Microbial Bio-fertilizers
Biofertilizers has been acknowledged as a substitute to chemical fertilizers to increase soil fertility and crop production in sustainable farming. Biofertilizer is a substance comprised of living microorganisms which, when applied to seed, plant surfaces or soil, inhabits the rhizosphere or the interior of the plant and stimulates growth by increasing the supply or availability of primary nutrients to the host plant (Vessey, 2003). A few of the new, common biofertilizers currently being used are rhizobium, azotobacter, azospirillum, cyanobacteria, azolla, phosphate solubilizing microorganism, arbuscular mycorrhiza, silicate solubilizing bacteria and rhizobacteria. Many of these biofertilizers help with nitrogen fixation and others help by serving as bioprotectants or biostimulants for plants. Phosphorus availability can also be improved, although the efficacy can vary depending on crop species, formulation, soil amendments, soil pH/type, and weather conditions.

Aeroponics
Aeroponics is an agricultural system that produces plants with the lack of soil. Aeroponics offers an effective method to produce plants, including fruits and vegetables, without potting and repotting them to replace their access to nutrient-rich soil. Plants are placed in soilless growing media frames that leaves the roots suspended in the air. Nutrients are provided to the suspended roots via air and mist. There are many types of aeroponic systems and depending on the system, nutrients can be manually or automatically applied. Most aeroponic systems possess one or more pumps that can be programmed to automatically nourish the plants without heavy supervision. Aeroponics do provide advantages over traditional soil grown crops. One benefit of this system is the capability of growing vertically and horizontally depending on space availability. Another advantage is the noticeable decrease in labor intensity (Buckseth et al., 2016). Without having to prepare soil and testing for the right qualities needed, most of the labor for aeroponics comes from harvest. Lastly, two of the more pertinent advantages is the ability to extend growing seasons and reduce pest and disease thresholds. However, there are a few disadvantages, but the higher concern would be the cost of startup and maintenance on an aeroponic system, as they can be costly depending on complexity.

Biodegradable Mulches
Biodegradable plastic mulch (plastic BDM) provides crop production benefits parallel to polyethylene (PE) mulch but it conserves time and energy by being able to be tilled into the soil once harvest is completed (Ghimire et al., 2018). Plastic BDMs offer a likely solution to disposal and environmental issues linked with PE mulch use. However, weed management and durability are the key factors that must be comparable or excel PE in order to be a viable alternative for organic crop production (Ghimire et al., 2018). Plastic BDMs are mostly produced from natural raw materials that can be considered biobased, derived from fossil fuels or a combination of the two. Recently, there have been some studies that have researched the biodegradability and effectiveness of plastic BDMs. The studies so far are promising but are still in the early stages.

Cover Crops
Cover crops have often been used in the past but today their popularity is steady increasing. In the past, it was well known that cover crops help replenish nutrients in the soil for cash crops to be grown but today cover crops are used to provide a variety of functions. As more and more research has been done, cover crops have been found to have many functions, many of which are connected to cover crop efficiency. These functions include weed suppression, soil nutrient retention, soil erosion control, and organic matter addition. The incorporation of diverse cover crop varieties is a new trend that has been found to have a positive effect. This is important because in past years, farmers have used the same cover crop annually, but this new discovery could bring forth new practices. Cover crops that possess allelopathic properties have been linked to the suppression of weeds which can limit the amount of labor hours used for weed management. Also, it is obvious how important organic matter is in an organic system, so having diverse cover crops that can be till into the soil will increase the organic matter composition.

Organic Certification
Being USDA organic certified has huge implications in the market. However, many consumers are not aware of the levels of organic certification. There are different levels of USDA organic certification. Certified products with 100% organic ingredients can say 100% Organic and display the USDA Organic seal. Certified products with 95% organic ingredients can say Organic and display the USDA Organic seal. Certified products with a minimum of 70% organic ingredients can say "Made with Organic Ingredients" but may not display the USDA Organic seal. Products made with less than 70% organic ingredients, or products that are not certified, can only list individual ingredients that are organic in the product"s ingredient statement. The required ingredient list is the only place the word "organic" can appear on the entire package for these products (Connolly, 2015).

Benefits of Organic Certification
One of the fastest growing agricultural sectors has been organic agriculture. This industry has provided the US with economic growth, creating jobs and agricultural awareness. Figure 1 shows the certified organic growth in the United States over the last few years. Becoming organic certified has its perks and benefits. Many farmers and growers proudly promote their organic certification once the certification process has been completed. The USDA Organic seal can be placed anywhere on the product or packaging once certification has been obtained. Furthermore, sometimes when it comes to marketing, the organic seal is the only marketing tool needed in order to get consumers interested. The desire for organic products has been and continues to thrive and become more popular.
Consumers are constantly pursuing products that are organic, healthy, natural and good quality. Not only are the products a marketing tool but consumers knowing that a producer is openly using organic, high quality production techniques to produce better products will draw the attention of the growing organic society. Spotting "Organic" on a food package is a massive attraction for this audience. If a product is not certified organic, which means "organic" can only be used in the ingredient listing, many buyers will not realize the product has an organic association. According to (Connolly, 2015) about 25 percent of consumers browse the ingredients of a product and recognize that organic ingredients were used to make the product. If that is the case, then there is nearly 75% of unaware buyers that are not knowing the organic certification importance of your product, which is a big economic disparity. This is important because consumers are willing to pay more for organic labeled products. There are many factors that can influence this decision such as peace of mind knowing how the product was produced, wanting a healthier lifestyle, looking for a different taste or type of food, desiring to help protect the environment and others.
Customers know that organic brands are united with a healthy lifestyle and care for the environment. In the big picture, customers know that harmful ingredients are not used if the product is labeled organic. Some will take a quick glance at the ingredient list to confirm no harmful ingredients have been used. When a brand makes a product that is well trusted by consumers, they are not just buying that particular product. The brand gains trust and able to get consumers to buy into the brand, not just the organic product, which means they will be inspired to purchase other items made from that particular brand (Connolly, 2015)

Organic Certification Process
The major steps involved in the certification process under the USDA NOP are highlighted below (Nandwani, 2018): Step 1 Submission of an application to a certifier by a farmer: This application contains several documents such as organic system plan; map of the farm; field histories; operator agreement; and report of organic yields and sales.
Step 2 Reviewing the application by the certifier: The certifier will read through the application and assess whether the farm meets the regulations and specifications.
Step 3 The inspector visits the farm: Organic farms are usually inspected annually. However, an impromptu visit may be carried out, usually at the discretion of the certifier. At the end of inspection, the inspector reviews any areas of concern. A report is written by the certifier which is forwarded to the certification agency.
Step 4 Reviewing the inspection report: A decision is made after reviewing the report by the certifier whether it conforms to the standards and regulations.
Step 5 Issuance of the organic certificate. It is worthy of note that organic farmers that gross less than $5000 from sales of organic products are exempt from the certification requirement (Klonsky, 2010).

Future of Organic Production
Diversification is a key agroecological principle of organic agriculture. Diversification in organic agriculture provides positive outcomes including increase biodiversity, pollination, pest management, soil fertility, disease management, and yield stability. It is believed that demand for organic foods will continue to increase, therefore larger and more organic farms will be needed. In areas where organic agriculture is thought of as superior and worthy, farmers will benefit from the premium prices and consumers will be pleased with the organic products. In food secure developed countries, organic farming will serve a great food production significance. For underdeveloped countries, organic agriculture could be a good fit due to synthetic chemicals being too expensive. As far as organic production in the US, a consistent rise has been the trend for almost 2 decades and is anticipated to continue that tendency.


extfieldsofstudy:
Medicine
Computer Science

provenance: AgriculturalAndFoodSciences,2019-2020-Agricultural And Food Sciences-2020.jsonl.gz.gz

text:
Biodegradable Food Packaging Materials and Prospects of the Fourth Industrial Revolution for Tomato Fruit and Product Handling

The environment and food safety are major areas of concern influencing the development of biodegradable packaging for partial replacement of petrochemical-based polymers. This review is aimed at updating the recent advances in biodegradable packaging material and the role of virtual technology and nanotechnology in the tomato supply chain. Some of the common biodegradable materials are gelatin, starch, chitosan, cellulose, and polylactic acid. The tensile strength, tear resistance, permeability, degradability, and solubility are some of the properties defining the selection and utilization of food packaging materials. Biodegradable films can be degraded in soil by microbial enzymatic actions and bioassimilation. Nanoparticles are incorporated into blended films to improve the performance of packaging materials. The prospects of the fourth industrial revolution can be realized with the use of virtual platforms such as sensor systems in authentification and traceability of food and packaging products. There is a research gap on the development of a hybrid sensor system unit that can integrate sampling headspace (SHS), detection unit, and data processing of big data for heterogeneous tomato-derived volatiles. Principal component analysis (PCA), linear discriminant analysis (LDA), and artificial neutral network (ANN) are some of the common mathematical models for data interpretation of sensor systems.

Introduction
The global population is about 7.8 billion in 2020 and is estimated to reach 10 billion in 2050 [1]. The increasing population, urbanization, variability in diet, and climate change put pressure on food security including postharvest of fresh produce. The major loss of fresh produce occurs at the postharvest stage [2]. The fresh produce including tomato fruit is perishable due to high moisture content [2]. Generally, postharvest losses (30-50%) of the fresh produce are associated with handling, storage, and packaging. The bulk nature of produce along the supply chain makes it difficult to monitor and control losses. Nevertheless, digital technologies including smart packaging innovations are considered suitable for tracking and controlling postharvest losses. The application of these smart logistic technologies finds use in product traceability systems on information that relates the product to its genetic factors and environmental conditions [3]. Furthermore, IFPRI [3] stressed that digitalization focused on the ecosystem including agricultural production, processing, transportation, and market system can enhance the food value chain and improve competitiveness. This necessitated the concept of digitalization of logistic systems including food packaging and market services. However, the use of synthetic plastic materials in food packaging can have an adverse effect on climate and the environment [4]. Hence, ecofriendly packaging materials are increasingly becoming the alternative. Muller et al. [4] reported that polylactic acid and starch are potential materials to replace synthetic polymer films, i.e., plastics food packaging materials. Moreover, Jeevahan et al. [5] reported that edible biofilms are compostable and can be manufactured from the polysaccharides, proteins, and lipids. The production of edible biofilms is a recent approach to generate biodegradable food packaging safe to humans and the environment. In addition, Guerrini et al. [6] reported that biodegradable films have physicochemical and mechanical properties suitable to replace common polymerplastic applications. However, the food industries are facing a range of challenges from climate change, increasing consumer safety demands, and subsequent issues relating to government policies and legislative requirements [7]. The environmental concerns associated with the nonbiodegradable nature of plastic biopolymers are impacting negatively on the ecosystem. In view of this, there is an increasing demand to replace synthetic plastic materials with biodegradable materials. This review is aimed at gathering recent advances in biodegradable packaging film materials and their performance on the quality of tomato. The role of virtual technology and nanotechnology in the tomato supply chain is highlighted in response to fourth industrial revolution.

Importance of Food Packaging
The economic value of packaging is reflected in the packaging conversion industry, packaging supply chain, and in the retail industry. In 2015, the packaging industry recorded revenues of $839 billion worldwide [8] and was projected to grow by 3.5% by 2020. Western Europe and Americas are the largest consumers of packaging. The packaging industry contributes~2% to gross domestic product (GDP) of the South African economy. The global demand for bio-based food packaging material is forecasted to reach~1 million tons per year by 2020 [9]. The packaging material is considered as the major component in the sustainable development goal number 12 focused on themes (climate action, ocean action, plastic pollution in the ocean, food loss and waste, and sustainable transport) that relate to sustainable consumption and production. Food packaging provides protection and preservation of food by making a physical barrier against contamination due to foreign matter and environmental-related factors. This ultimately contributes to extended shelf life of food product. Other functions include mechanical and physical strength, convenience, and communication through product labeling [10,11]. The actors in the value chain specific to food packaging include food processors, farmers, retailers, and researchers [12]. Postharvest strategy of minimizing loss through the packaging of tomato along the supply chain results in extended shelf life, improved income, livelihood, and food security [13]. Recent development in novel food packaging is driven by consumer's demand for convenience, ready to eat food, shelf stability, and maintenance of food quality [14]. The plastic polymers have been utilized for food packaging material production due to their availability and simplicity of manufacturing [15]. The petroleum polymers are hardly degradable and thus causing defects in the ecosystem [15]. Moreover, O'Brine and Thompson [16] reported that polymer plastic materials may take over 100 years to decompose. Similarly, Webb et al. [17] reported that polymer plastics that are landfilled could take longer than 20 years with no change in the plastic property. Hence, there are developments to replace petroleum-derived plastic with biodegradable materials. The innovation and development of food packaging from renewable, compostable, and biodegradable to active and intelligent packaging were reported [18,19]. In addition, barrier properties, compatibility materials, and shelf life extension properties of the innovative packaging determine selection and utilization [18,19]. The environmental safety concerns are limiting the use of plastic films for packaging in the food industries. Consequently, biopolymer films are receiving attention due to their biodegradable properties.

Overview of Biodegradable Packaging
The utilization of biodegradable materials on the markets of North America, Europe, and Asia has grown in the range of 15-20% CAGR from 2012 to 2017 [20] but the market data for Africa is not well established. Atarés and Chiralt [21] reported the application of essential oil in biodegradable food packaging films in Spain for the production of bio-based packages with potential health benefits (antioxidants and antimicrobial properties). The lipid nature of essential oils can decrease water vapor permeability in hydrophilic materials and can also improve the structural, mechanical, and optical properties of packaging films. The biodegradable packaging films developed and tested on tomato fruit in Finland for preservation objectives resulted in extended shelf life [22]. In Malaysia, Ali et al. [23] demonstrated the use of gum arabic as edible coating film for extending the shelf life and postharvest quality of tomato. Starch edible coatings derived from Colombian native potatoes were applied on Andean blueberry (a wild fruit native to South America) resulting in reduced respiration rate of~27% [24]. However, previous works recommended further research focused on the improvement of the physical strength of biodegradable films comparable to that of petroleum polyfilms [22]. Sanaa and Medimagh [25] reported biomass materials that can be used to produce biodegradable and biopolymer in Africa: the vegetable cellulose extracts from cotton fibers in South Africa; Luffa Cylindrica in Nigeria; Washingtonian filifera in Algeria; Napier grass in Botswana; Hibiscus sabdariffa in Kenya, Ethiopia, and Uganda. The biopolymers such as chitosan, cellulose, and pectin were given attention in the manufacturing sector of food packaging and the research community [25]. Moreover, in Ethiopia, the film produced from pectin and chitosan extract and tested on tomato resulted in extended shelf life (15-17 days) compared to the control (10 days). Furthermore, in Nigeria, reports show that there is an intensive production of biodegradable plastic film from blending cassava starch and biodegradable polymer materials. Postharvest loss of fresh tomato on the market was reported to be 9. 50, 9.80, and 10.04% in Eastern, central, and southern African countries of sub-Saharan countries, respectively [13], with Kenya, South Africa, and Nigeria recording 10.10, 10.20, and 13.40% postharvest losses, respectively [13]. Nevertheless, reduced postharvest losses among commercial or emerging farmers of tomato were achieved with the use of recyclable cardboard boxes of various sizes, bulk bins, plastic crates, and wooden crates for packaging and transportation in the South African supply chain [26].
Food packaging films can be produced either by lamination, casting, coextrusion, or coating processes from the raw plastic polymer, biopolymer, and biodegradable materials [10] (Table 1). The food packaging film is extracted from biopolymers, including gelatin, starch, cellulose, and bio-derived monomers such as polylactic acid [27]. The bacteria-derived compounds include cellulose, xanthan, curlan, and pullulan [19]. Chitosan is a natural polymer, nontoxic, edible, and biodegradable derived by deacetylation of chitin which is the second most abundant biopolymer in nature after cellulose [28]. Supplementation of different kinds of additives is recommended to improve the properties of the biodegradable film [27]. The edible biodegradable films can be stabilized by material components of hydrophilic nature such as proteins or polysaccharides. The production of films or coatings involves casting film-forming aqueous dispersions and subsequent drying. The essential oils (additives) are added to film during dispersion phase, and the mixture is achieved by homogenization or emulsification processes [21]. Thus, the dried polymer can be a structural matrix of the film and lipid droplets [21] including hydrocolloids such as edible fats, fatty acids, proteins, and polysaccharides [29]. Ivankovic et al. [19] reviewed that there are three generation stages of biodegradable polymers from which biodegradable food packaging materials can be manufactured. Accordingly, the first generation is low-density polyethylene (LDPE) film consisting of 5-15% starch filters and autoxidative additives. The second-generation films are composed of 40-70% pregelatinized starch, low-density polyethylene (LDPE), and hydrophilic copolymer additives. The third-generation materials are produced from biomaterials and can be classified into (a) polymer extracted from biomass such as starch, chitin, chitosan, plant proteins, and soybeans; (b) polymers synthesized from bio-derived monomers including polylactate and other polymers; and (c) biomonomers and polymers produced from natural or genetically modified organisms. The nanocomposite materials were identified to possess superior characteristics such as high performance, lightweight, and environmentally friendly compared to plastic food packaging materials [30]. The low cost, renewability, and availability of biopolymer are some of the desirable considerations applicable for thermoplastic starch-based food packaging materials [31].
The fruits coated with gum arabic soybean gum, jojoba wax, and glycerol resulted in delayed in changes of weight loss, firmness, and titratable acidity including delayed softening of tomato [23,32]. The tomato fruits coated with 10-15% gum arabic film yielded less weight loss during storage period than the control sample [23]. This suggests that gum arabic film exhibited effective semipermeable barrier against O 2 , CO 2 , moisture, and solute movement, which probably decreased respiration, water loss, and oxidation reaction rates. de Jesús Salas-Méndez et al. [33] reported that the mixture of edible coatings (whey protein, glycerol, and candelilla wax) and Fluorensia cernua extract coated on tomato inhib-ited~40% growth of pathogenic fungi. The mixture of 0.75% chitosan and 2 mM cinnamic acid coated on tomatoes yielded high firmness after 12 days of storage [34]. The film made from chitosan colloids and grapefruit seed extract (0.5-1%) inactivated Salmonella on cherry tomatoes during storage [35].

Preservation Mechanism of Edible Coatings.
Quality deterioration of fruits is in function of biochemical processes in the cell structure, cell wall composition, and intracellular materials. Cellulase and polygalacturonase are two major cell wall hydrolase enzymes and were shown to correlate with softening and ripening of fruits [36]. Edible coating of fruits can delay ripening by lowering permeability of O 2 resulting in increased intracellular CO 2 . High levels of CO 2 can limit the activities of cell wall hydrolase enzymes and allow retention of the firmness during storage [23]. This effect of a lowoxygen environment is readily used for optimizing storage conditions and transport and for prolonging the shelf life of several fruit commodities [37]. Decreasing respiration rates of coated tomatoes could be responsible for delayed ripening and can result in reduced changes in physiological weight loss, color, titratable acidity, and retention of firmness [23]. The antimicrobial properties of edible coatings [38] can protect the fruit against firmness-degradative agents such insects and mites [39] which are carriers of fungal and bacterial spores [40] and can cause spoilage and softening of ripe tomato fruits [41]. The biodegradable packaging materials applied on fruits including tomato are decomposable and can be degraded by microorganisms in the soil [6,42,43].

Biodegradation of Biodegradable
Films. Soil microorganisms can degrade biodegradable materials into natural compounds such as water, carbon dioxide, and methane including monomers such as amine, alcohol, and carboxylate acid ( Table 2). Biodegradability is in function of chemical composition, nature of bonding, and water availability. The appearance of IR spectra peaks for carbonyl signals is indicative of enzymatic degradation of starch into maltose (disaccharide) and glucose (monosaccharide) [44]. The microbial action is enzymatic nature. The microbial cells exhibit saprophytic growth utilizing plant-derived metabolites as substrates [45]. The microorganisms secrete an array of amylases and cellulases responsible for enzymatic hydrolytic and oxidative breakage of glycosidic bonds in starch and cellulose. The extracellular enzymes such as esterase, cutinase, and lipase hydrolyze labile aliphatic ester linkages of plasticizing films [46]. These enzymatic processes generate metabolites that are absorbed by microorganisms for energy requirements. This is evident in the decrease and disappearance of IR spectra carbonyl signals with time. Tai et al. [44] showed significant peaks of carbonyls in 30 days and decrease after day 45, which suggested starch/cellulose breakdown and metabolite absorption, respectively. Enzymatic depolymerization of chitosan showed a sharp increase of sugars with time during 15 h and slower in 15-24 h [47]. The slower decrease of metabolites is indicative of the saprophytic phase. UV light irradiation with wavelength < 350 nm can cause chain scission of polymer molecules and can also accelerate enzymatic activity. Combined treatment of UV irradiation and cellulase enzyme degraded 60% of cellulose 3 International Journal of Food Science acetate compared to UV treatment (23%) in 7 weeks [48]. Biodegradation process is commonly characterized using thermalgravimetric analysis (TGA) reflected in three-stage degradation profiles; the first degradation corresponds to loss of water and volatiles, the second stage relates to the formation of starch subunits of lower molecular weight, and the third stage is associated with breakdown of starch components [46,49]. The degradation of biodegradation film is in function of microbial activity in soil and water, hydrophilic nature of plasticizer, surface area of the sample, crystallinity, molecular weight of the sample, and temperature. The addition of plasticizers increases the number of polar groups and water permeability in the samples and accelerates the interaction of polar groups with water [50]. Plasticizers of biosurfactant nature possess excellent surface/interface activity and biocompatibility [51] and enhanced soil hydrocarbon bio-degradation by lowering interfacial tension between soil and water [52]. Increased yields of metabolites such as volatile fatty acids were shown at optimal pH 10 under controlled fermentation process [51]. Higher pH levels can inhibit acidophilic bacteria and subsequently limiting the production of metabolites. The pulsed electric fields treated zein-chitosan-poly(vinyl alcohol) film had enhanced stability of films against electrolyte and enzyme degradation [53].

Properties of Biodegradable Films
3.3.1. Structural Properties. The chemical structures and composition of packaging materials can be examined using Fourier transform infrared (FT-IR) spectroscopy and atomic force microscopy (AFM) [72]. Diffraction method using Xray diffraction has been applied in the assessment and  International Journal of Food Science quantification of amorphous and crystalline structures in starch. The crystallinity is strongly associated with amylopectin molecule. Amylose is largely found in the amorphous lamellae, and amylopectin forms crystalline lamellae of the starch granule [73]. Crystallinity influences dispersion characteristics such as swelling of starch in plasticizers [73]. The IR spectrum is commonly characterized by the interaction of chemical bonding with IR radiations. IR spectrum for starch films exhibited broad band due to vibrational stretching of hydroxyl (-OH) groups linked inter-and intrachain. The narrow bands were associated with stretching of C-H bonds while the peaks related to carbonyl (C=O) groups attached to the ring of glucose [74]. The surface microscopic analyses of film structure were examined using scanning electron microscopy and transmission electron microscopy [75,76]. Starch and PVA films exhibited homogenous and smooth surfaces. The cross-section of the films was the characteristic of heterogeneous and irregular (bubble like) structures which varied with degree of crystallinity. The film blends (PVA/starch) are characteristic of microstructure phase separation due to inadequate miscibility, differences in crystallinity, and extrusion method. Compatibilizer compounds such as formaldehyde and poly(ethylene glycol) are blended with films to prevent phase separation blended films [77]. Factors influencing phase separation include proportional of starch and phosphate groups in the amylopectin chain. Potato starch film did not exhibit phase separation owing to the presence of higher content of phosphate groups than other native starches. The thickness of the films determined using SEM was reported, and film blends showed higher thickness than pure starch. The differences in thickness were due to variation in molecular weight. Higher molecular weight yielded higher thickness [78]. Biodegradable edible packaging material (coating or film) has a recommended thickness of less than 254 μm [9].

Permeability
Properties. The polymer matrix must exhibit effective permeability of gases for increased shelf life of food products [29]. The shelf life and freshness of vegetables and fruits including tomato are directly related to the transfer of water between the produce and the surrounding atmosphere. Thus, the primary role of packaging is to reduce the transfer of water. The poor moisture barriers in edible films were due to the hydrophilic nature of polysaccharides [29]. Lipids are hydrophobic in nature, and their inclusion in chitosan and polysaccharide films contributes to improved water vapor barrier properties. The entanglement of hydrogen bonding between NH 2 group of chitosan and OH group of plasticizers (e.g., CAP and PVA) increased hydrophobicity of blended films (CAP/chitosan and PVA/chitosan) resulting in six reductions in water transfer rate [79]. Furthermore, Yu et al. [79] demonstrated that the addition of silica TGA: thermalgravimetric analysis; CRV: carvacrol (CRV) essential oil (2-methyl-5-(1-methylethyl)-phenol); PEF: pulsed electric fields.
5 International Journal of Food Science nanoparticles into biodegradable films decreased permeability of moisture. Depending on the respiratory requirements of the product and polar molecular of packaging material ingredients, oxygen permeability properties can be altered by incorporating PVC, chitosan, and silica. Oxygen permeability values were reduced by~26% when silica was incorporated into PVA/chitosan biodegradable films [79]. The equilibrium-modified atmosphere packaging (EMAP) finds intensive application in the packaging of fresh fruit and vegetable including tomato. The EMA packaging optimizes gas transport properties according to the respiratory requirements of fresh produce. The equilibrium atmosphere is attained when the exchange of gases through the film is in steady state with the production or consumption of gases due to the respiration and transpiration processes of the fresh produce [72]. The gas transport properties can be adjusted by perforation through macroperforation and microperforation using mechanical and laser procedures, respectively [72]. Among the alternative biopolymers, starch and polylactic acid (PLA) are the major materials of interest in the research community.

Mechanical Properties.
Zhou et al. [80] developed biodegradable polylactic films using pea starch and polylactic acid for cherry tomato packaging film. However, biodegradable polylactic film exhibits poor mechanical properties compared to petroleum polylactic films [80,81]. The biopolymers such as starch are associated with brittle films. The incorporated hydrophilic plasticizers such as polyols (glycerol, sorbitol, and polyethylene glycol) into film-forming dispersions decreased intermolecular forces and increased mobility of polymers resulting in increased flexibility and extensibility [82]. The mechanical properties (compression test, tensile strength, and strain) including film-forming capacity of the film are associated with polymer crystallinity and amylose content [82], molecular weight properties, and their distribution and concentration of additives. Plasticizing agents such as polyvinyl alcohol (PVA) and cellulose acetate phthalate (CAP) can change the mechanical behavior owing to the formation of inter-and intramolecular hydrogen bonds. The blend of starch and PVA yielded biodegradable film with better mechanical performance [83]. The film blend of chitosan-CAP and nanoZnO recorded higher tensile strength than pure chitosan film [84]. The increase in tensile strength in film blends is indicative of better interaction among the components of the film. The tensile strengths of the films increased with increasing diblock copolymer [85]. Inclusion of plasticizers and nanoparticles into starch films increased and decreased elongation at break, respectively (Table 3). Nanofillers provide reinforcement and increase interfacial bonding interaction in the film matrix. Lower molecular weight yielded higher tensile strength and elongation at break of starch films. The decrease in brittleness can be achieved by blending PLA with plasticizers such as polycaprolactone (PCL) [86]. However, the PLA-PCL blends exhibited poor gas barrier properties but can be improved using suitable fillers such as highly dispersed nanoparticles [86]. There is a need for increased research objectives to improve the mechanical properties of the biodegradable polylactic film using nanoparticles in response to the respiratory requirements of tomato fruits. Rhim et al. [87] reported that drawbacks in biodegradable polylactic film limit their full utilization in the food industry. Some of the limitations are thermal instability, low heat sealability, brittleness, lowmelting length, and high water vapor and oxygen permeability [87]. Moreover, the hydrophilic nature of some biodegradable biopolymers was characterized with low water vapor barrier and consequently exhibiting weak mechanical properties [88,89].

Solubility Properties.
The solubility values of biodegradable films are in function of hydrophilic nature of polymers. The solubility of starch film (0.208 g dissolved /g dry film ) and PVA (0.19 g dissolved /g dry film ) decreased in the film blend of PVA/starch (0.11 g dissolved /g dry film ) [90]. This suggested a decrease in the hydrophilicity of the film matrix. The entanglement of hydrogen and hydroxyl bonding between polymers can lead to structural reorientation, thus exposing the hydrophobic nature of the film matrix and subsequently, decreasing water affinity. Nevertheless, Pellá et al. [91] reported higher water affinity of films in blended potato starch/PVA than those of pure films (Table 3). This was ascribed to an increase in -OH groups. Sajjan et al. [92] reported that lower solubility values are indicative of films with good stability in aqueous medium and are recommended for packaging applications especially for storage.

Optical
Properties. The color parameters (L * , a * , and b * ) and color difference (ΔE) are commonly measured using CIE system [93] while transmission of light and transparency [94] can be measured using UV Vis Spectrophotometer [93]. Prolonged exposure to UV and visible radiations can discolor and deteriorate the packaged food products. In view of this, transparency and UV-screening ability of packaging films are vital parameters in quality control. Generally, synthetic plastic films (low-density polyethylene and polypropylene) were reported to have lower screening ability against UV radiation [84]. The blended films loaded with nanoparticles exhibited higher absorption peaks (wavelength) than pure films. The higher surface area of nanoparticles increased the UV absorption capacity of the polymer matrix [75]. The nanocomposites (ZnO and nanoclay) increased the opacity of starch films, suggesting that nanoparticles are UV blockers and thus minimize the penetration of light.

Advances in Packaging Technology
The packaging technologies for food applications include active, intelligent, smart, modified packaging, controlled packaging, and biodegradable coatings.

Active Packaging. Inclusion of antimicrobial components
is an aspect of innovative food packaging technologies such as active and intelligent packaging [96][97][98][99][100][101]. Active packaging is material components with the capacity to protect the packaged food from microbial proliferation [102] and provide information about the quality during transport and storage. The petroleum-based polymeric materials are commonly applied in active packaging [103]. However, environmental 6 International Journal of Food Science and safety concerns have driven research and development in packaging towards bioactive materials [103]. Active materials are intentionally added to packaging material or packaging headspace to prolong shelf life through a controlled release of antimicrobial compounds [104]. Active food packaging was developed to respond to the food market demand for improved quality of fresh produce and maintaining safety [96]. Tomato fruits preserved using active packaging resulted in extended shelf life [96], improved safety, and maintained sensory properties [97,98]. Essential oils with antimicrobial and antioxidants activity are incorporated into food packaging films to produce active packaging materials and thus contributing to the preservation of the food [105]. Essential oils inhibit the growth of microorganisms [105]. Moreover, Azmai et al. [106] reported that coating with chitosan and cinnamic acid improved the quality attributes such as firmness and total soluble solids, reduced physiological weight loss of tomato, and prolonged the shelf life. However, global migration of compounds from packaging material into food is a food safety concern and can cause contamination [107]. Bradley et al. [108] postulated that intelligent food packaging can cause toxicological risk, environmental contamination, and problems with recovery and recycling of the packaging materials. The package of active biodegradable corrugated cardboard tray tested on cherry tomato was reported to extend the shelf life of tomato for a month [96].

Active
Scavenging and Adsorbents. The liquid exudate from fresh tomatoes influences sensorial and microbial quality [109]. The adsorbent pads are designed to take up the exudate and ultimately preserving integrity and quality of packaged products [110]. The active scavenging systems remove gases such as CO 2 , O 2 , and ethylene from the package or container. The presence of oxygen in package accelerates oxidation or spoilage. The decreased reactive oxygen species was associated with delayed overripening and decreased susceptibility to Botrytis cinerea [111]. The role of scavenging was achieved using flavonoids produced from different tomato varieties [111]. Ethylene scavengers (KMnO 4 , activated carbon, clay, and zeolites) have been applied on fruits and vegetables including tomatoes. The KMnO 4 transforms ethylene into acetate and ethanol. Cherry tomato treated with 0.1% (v/v) ethanol during storage resulted in elevated ascorbic acid, sucrose, and fructose contents, inhibited ripening, and improved sensorial quality [112]. The KMnO 4 -based technology has been reported to have a limited commercial application due to uncertainties on its effectiveness as postharvest tool and also concerns relating to health, environmental, and safety [113]. However, KMnO 4 -promoted nano zeolite was reported to show high ethylene removal efficiency [114]. The condensation due to transpiring tomatoes can lead to accumulation of moisture. The removal of moisture can be achieved using active element (silica gel, polyacrylate  International Journal of Food Science salts, zeolites, and microporous clays) in the packaging system [115]. A sodium polyacrylate-cotton mixture applied as moisture adsorbent in the form of sachets resulted in noncondensation of water in active packaging system of tomato fruits [115]. The preservative releasers based on the blend of itaconic acid and chitosan enriched with tomato bioactive extract yielded significant antimicrobial effects on packaging films [116]. Other preservative releasers applied in packaging system for tomato include silver zeolite, organic acids, spice/herb extract, vitamins C and E, sorbates, chlorine dioxide/sulfur dioxide, and benzoates and propionates [117].

Intelligent and Smart
Packaging for Tomatoes. Intelligent packaging is a packaging that comprises of external or internal indicators that give information about the history on safety and quality of the product [104]. Vanderroost et al. [118] reviewed that smart or intelligent packaging technologies offer the opportunity to record and detect changes in the packaged product and its environment [118]. Intelligent packaging tracks the history of the food along the supply chain [97]. For instance, Bartkowiak et al. [119] reported that the lactic acid-based time-temperature indicators [102] provided history on quality and time-temperature of lactic acid-based food. Hence, this application can find use in tomato and tomato-derived products that are acidic in nature. However, a few of such technologies were commercialized, partly due to higher cost of investment. Lee et al. [97] suggested low-cost intelligent packaging material production for food industries.

The Fourth Industrial Revolution in Packaging and Tomato Supply Chain
The major technological drivers for the fourth industrial framework (4IR) are physical, digital, and biological technologies [120]. The appropriate technology driver for packaging and tomato supply chain is digital technology which includes fields such as artificial intelligence and robotics, linked sensors (Internet of Things), virtual and augmented realities, additive manufacturing (3D bioprinting organic tissues), advanced materials, and nanomaterials [121]. In agricultural production, the digital technology finds application in areas of smart sensing and monitoring, smart control, smart analysis, and planning [122]. The notable digital technology in packaging and tomato supply chain is the use of sensors and electronic nose for classification and discrimination of germplasm of food crops, quality control, and verification and authentification of geographical origin. Traditionally, wet extraction and analysis is a common laboratory approach of obtaining key trait information about tomato germplasm in different agroecological zones; however, this approach involves the use of chemicals which are detrimental to the environment and human safety. Levin [121] outlined methodological approach required to achieve smart sensing digital systems in the quality analysis of food crops: (i) sample handling systems, (ii) detection systems, and (iii) data processing systems (Table 4).

Sample Handling
System. The conventional isolation techniques for volatile compounds such as steam distillation and solvent extraction can cause modification to quantity and quality of flavor profiles in samples [123]. In addition, these techniques are destructive and time-consuming. The rapid techniques include the purge and trap headspace sampling method [123,124]. The headspace can be in static or dynamic mode. This method involves trapping and concentrating volatile compounds on a solid support which is then heated to release volatiles into gas chromatography (GC) or GC/mass spectrometer (MS) systems containing sensing elements. The purge and trap and dynamic headspace sampling were used to extract the flavor compounds from tomato fruits [125,126]. The static headspace sampling methods in tomatoes [127] extracted a true reflection of flavor profile but yielded low amounts of compounds, suggesting loss of volatiles during sample handling and may result in undetection. Such shortcomings were eliminated with the use of cold trapping static headspace. This cryofocusing technique allows samples to be concentrated without heating. The solid-phase microextraction (SPME) is a user-friendly preconcentration method. In this technique, volatile components interact and react with fiber-coated probe inserted into the headspace of a sample and then transferred to a GC injection port where the volatiles are desorbed. The SPME has been applied in the analysis and discrimination of volatiles in tomato landraces [128]. The stir bar sorptive extraction is another sampling technique in which a magnetic bar coated with polymers is suspended in the headspace. This technique is similar to inside-needle dynamic extraction method, a preconcentration technique in which absorbing polymers are fixed inside the needle, and enables the interaction of polymers with volatiles [129]. The mechanism of volatile release, different types, and factors guiding the selection of stir bar sorptive were reported [129].

Detection
System. The detection system is the application of an array of sensors operating as devices to identify chemical compounds in the headspace. Chemical sensor transforms chemical quantity into an electrical signal in function of the concentration of specific atoms, molecules, or ions in gaseous or liquid forms [124,130]. The sensors applied in e-nose are capable of responding to molecules or particles which are volatile in nature and can vary with relative molar masses. Several sensor arrays used in the development of enose have been reported. Piezoelectric sensor is a device that utilizes acoustic waves generated by piezoelectric materials such as quartz or LiNbO 3 [130] to detect changes in pressure, acceleration, temperature, strain, or force and converting them to an electrical charge [131]. The acoustic (piezoelectric) impulse response parameters (dominant frequency, firmness index, and elasticity coefficient) yielded a good to strong correlation with firmness parameters (compression force and puncture force) of tomatoes during storage time [131]. Electrochemical sensors are devices that convert electrochemical reactions between an electrode and analyte into an output signal specifically related to the concentration or partial pressure of the gaseous species [132]. The types of electrochemical sensors include potentiometric, conductometric, 8 International Journal of Food Science amperometric, and voltametric but they have limited detection limits [130,[132][133][134]. The recent areas of research in electrochemistry involve the modification of electrochemical sensors using conductive materials such as nanoparticles to enhance their response and detection limits [135]. The sensitivity of a conductive material-based sensor is defined by change in the electrical conductivity of the semiconducting material when exposed to test volatiles. Nanoparticles such as spherical Cd 2 SnO 4 and Zn 2 SnO 4 provide large surface area for the absorption and have high electron density [136]. The electrochemical DNA sensor was developed to perform the direct determination in intact genomic DNA extracted from tomato seeds [137]. This suggests that electrochemical sensor can be used to discriminate the bionature such as organic or inorganic germplasm in tomato cultivars. Other detection systems include and optical and thermal sensors. The optical sensors which include absorbance, reflectance, luminescence, and surface plasmon resonance techniques [138] are nondestructive methods based on multispectral three-dimensional (3D) imaging [139]. The fertilizer application and irrigation water were optimized based on the reflectance characteristics of the canopy such as leaf temperature, leaf relative water content, and leaf chlorophyll content in the field of tomato [138]. Thermal sensors detect heat produced by a specific analyte in the chemical reaction. The different types of heat sensors include resistance temperature detectors (RTDs), thermocouples, thermistors, infrared sensor, and semiconductor sensors. Thermal sensing depends on analyte change of state in response to temperature and light. The signals of optothermal window/light-emitting diode correlated strongly with colorrelated quality parameters of tomato-derived products [140].
The problem associated with e-nose is that they tend to produce limited information by targeting specific measurements. In real time, the food ground matrix (fresh or processed) is a complex of interacting volatile constituents. Peris and Escuder-Gilabert [130] proposed a sensor hybrid system to generate different sensor outputs in a single spectrum. Nevertheless, this would require the application of more complex electronics combined with standardized sensor outputs. The problem associated with e-nose such as masking of sample constituents, influence of moisture, and nonlinearity of signals were solved by integrating e-nose system with mass spectrometry. The MS-e-nose integrated systems are a new technology that introduces volatile compounds into the ionization chamber of MS-based instrument that produces an output of ion-fragmentation patterns [130] representing a chemical footprint for volatile compounds in a sample. The MS-based e-noses find application in qualitative analyses of alcoholic beverages.

Data Processing
System. The sensor array output of samples is processed using pattern recognition techniques [141]. The interaction of volatile compounds with sensing elements produces changes in the electrical resistance of the sensor.
The changes in electric signals are different depending on the sensor kinetics and thus a variety of signals collected and remitted into data acquisition and processing unit in which a volatile fingerprint can be interpreted using appropriate mathematical recognition techniques such as principal component analysis (PCA), linear discriminant analysis (LDA), and artificial neutral network (ANN). The discrimination of geographical origin and identification of different 9 International Journal of Food Science olive oil varieties were achieved based on metal oxide semiconductor sensor using PCA and LDA and yielded~98% and 96% recognition success rates, respectively [141]. Optimization of recognition pattern requires the use of an array of sensors commonly in the range from 1 to 32 sensors. The sensors are evaluated using a loading analysis of PCA to identify significant patterns and their corresponding sensors. PEN2 with 10 different metal oxide sensors (MOS) was used to recognize the ripening state of tomato [142], and PCA biplot loadings showed that sensor MOS 2, 6, and 8 were located on the extreme positive coordinates of the biplot but MOS 2 had variance of~95% (please see figures in Gómez et al. [142]). This indicated that the three sensors were extremely distinguished; however, MOS 2 exerted higher influence on the ripening pattern of tomato. In addition, sensors 6 and 8 clustered together, which is an indicative of similarities in their response to ripening.

Applications of Virtual Platforms in Traceability.
The conductivity of sensors is in function with changes in physicochemical characteristics of the product. The sensor PEN2 e-nose (Airsense Analytics, GmBH, Schwerin, Germany) was used to detect quality changes (soluble solids content, pH, firmness, and vitamin C) in juice extracted from cherry tomato [143]. In the same study, Hong and Wang [143] analyzed the sensorial characteristics of tomato juice using α-Astree e-tongue (Alpha MOS Company, Toulouse, France). Berna et al. [144] compared two electronic nose systems, quartz microbalance-based electronic nose (E-nose) and a mass spectrometry-based electronic nose (MSE-nose) against gas chromatography (GC) as a standard reference in the analysis of aroma differences among tomato cultivars. The MSE-nose produced variation while E-nose hardly discriminated the differences among the cultivars [144]. The electronic sensories (e-nose and e-tongue) are commercial ready on the markets; however, their application would require validation studies specific to genetic factors, geographic locations, growth traits, and changes in postharvest handling and logistics. Other studies reported analysis of sourness, saltiness, and umami using electronic nose and electronic tongue coupled with gas chromatography-mass spectrometry (SPME/GC-MS) [145].
The unpredictable changes in supply chain, dynamics in quality, and regulatory system requirements for food safety and sustainability would require networked processes of virtualization to enable centralized operational management of food supply chains [146]. This is aimed at achieving a food supply chain that can be monitored, controlled, planned, and optimized in real-time using the Internet-based virtual objects instead of on-site physical observation [146]. The RFID (radio frequency identification), EPC global (Electronic Product Code), and ebXML (Electronic business using eXtensible Markup language) are some of the electromagnetic or electrostatic coupling technologies commonly applied to virtualization of supply chain traceability for commercial products including food and petroleum-based plastic materials. The European Union regulatory requirements for traceability of food contact materials are mandatory [147]. South Africa is among the major regional tomato producer in sub-Saharan Africa and ranks among the major exporters of fresh produce including tomato to the EU [148,149]. However, no information relates to the traceability of biodegradable packaging materials in the South African tomato supply chain. The authentification of biodegradable packaging can be assured by developing a footprint characteristic of a material component to enable digital differentiation between biodegradable and synthetic plastic packaging materials. The biodegradable packaging materials are considered suitable for organically produced agricultural products including tomato. Literature showed that there are several benefits of supply chain traceability including enhanced integrity of a supply chain, easy tracking of product from farm to consumer, tracing of products to their origin, avoiding the risk of inappropriate labeling of products, and improves effectiveness of product audits.
There are concerns with packaging labeling regarding the misrepresentation of package, package ingredients, and false statements aimed at making an economic gain. This desire to gain a profit by mislabeling of products is a concern in the markets. Consumers are increasingly becoming aware of the value of food quality and safety. The contaminants resulting from nonbiodegradable packaging materials represent an important food safety topic [150,151] and can lead to decreased consumer confidence in finished/processed food products. Subsequently, such safety concerns have stimulated interest in authentification and traceability for compliance with the regulations, consumer protection, and competition. The packaging products must reflect the origin of the material ingredients, details of postharvest treatments, and the geographic location ( Figure 1). Turci et al. [152] reported that the internal traceability has been established as the reliable approach of preventing fraudulent or deceptive labeling and also to certify originality and quality of tomato products on the market and their postharvest influencing factors including packaging material nature. The commonly documented parameters for authentification and internal traceability for tomatoes are protein [153], metabolite [154], and DNA [152]. There is a need to identify nanoparticle makers for traceability and authentification of biodegradable materials. The nanosensor signals expressed in nanometers are developed to detect changes in structural and functional properties of materials at nano level (1 nm = 10 −9 ) [155] and are embedded in food packaging material to monitor freshness of perishable products [156] during production, processing, and distribution. The suitability of nanomaterials is in function of good mechanical and electrical properties [157] and high surface area [155]. The tracking of food ingredients using nanosensor through the processing chain [158] suggests the potential application of nanodevices to monitor the ingredients of biodegradable materials. The structural differences between natural biopolymers and synthetic polymers [159] can be streamlined at nanoscale to develop differentiating markers. The data on structural and functional properties of material components in response to electromagnetic behavior can lead to the development of nanodevices to enable the identification of material ingredients and formulations. The biodegradable materials can be degraded by enzymatic action of living organisms (bacteria, yeasts, and fungi) and storage conditions (humidity and water). There is a gap in research for mathematical modeling relating to impact of degradability agents on the durability and mechanical integrity of biodegradable materials. The network of nanosensors can be implemented to achieve product monitoring and environmental conditions. The RFID and wireless sensor network (WSN) integration was suggested [160] to capture environmental information along with product tagging and thus assuring the end-user on meeting the system requirements throughout product delivery and storage such as maintaining the required temperature and humidity [160]. The loss of sensor data occurs due to corrupted network or hardware failure [160,161]. The missing data can be predicted by data mining techniques [160] using interpolation methods: k-nearest neighbors (KNN) [161], global refinement method Delaunay Triangulation, PCA, multichannel singular spectrum analysis (MSSA), and compressive sensing [161]. The RFID-WSN can be integrated with data mining techniques to incorporate the data due to changes in the storage conditions. The novel environmental space-time improved compressive sensing (ESTI-CS) algorithm [161] achieved environmental reconstruction with a minimal error of 20% for 90% corrupted network. However, there is limited information on the implementation of nanosensor technology in integrated sensor system.

Conclusions and Recommendations
The demand to replace synthetic plastic with biodegradable packaging materials is increasing. The development of biodegradable packaging is influenced by several factors including policy and legislative changes and world demand for food and energy resources. The biodegradable materials are associated with poor properties (high brittleness and low transparency). Nevertheless, the use of nanocomposite ingredients can improve brittleness and other physical properties. There are limited studies focused on interactions between the polymers and the food products. In addition, there are few studies that point to toxicities associated with the global migration of ingredients from a biodegradable package into the food. The appreciable use of digital platforms in the tomato industry to attain objectives of 4IR would require great amount of data to develop a hybrid sensor response in function of production (agronomy and genetic traits), postharvest treatment, storage conditions (temperature and relative humidity), quality traits, and geographical origin of genetic factors. There is a need to develop fingerprint markers to enable differentiation and authentication of biodegradable materials.

Conflicts of Interest
The authors declare that they have no conflicts of interest regarding the publication of this paper.


text:
Inoculation of Rhizobacteria to Red Chili Plant (Capsicum annum L.) in Saline Sandy Soil

Submited : 26/08/2019 Accepted : 31/01/2020 Abstract A red chili plant (Capsicum spp.) is one of the horticultural commodities in Indonesia which has good economic value, so it has priority to be developed. Agriculture practices in Java island have partly switched to coastal areas which have characteristics of saline soils. Saline soils are alkaline and nutrient-poor, especially essential nutrients such as P and N. One way to restore fertility in saline soils used beneficial and fertilizing bacteria such as PGPR. Plant growth-promoting rhizobacteria (PGPR) are free-living, soil-borne bacteria, which are capable of enhancing the growth of the plant either directly or indirectly. The objectives of this research were to determain the effect of PGPR isolates to the growth of red chili plants in saline sandy soil and to determine the best PGPR isolate capable to improve the growth of red chili plant in saline sandy soil. The result showed that the inoculation of rhizobacteria significantly affected to plant height and root length of the red chili plant (Capsicum annum). The combination of 3 PGPR isolates (Azospirillum PSA 10, Azotobacter PSA 8, and Marinococcus PSA 1) was the best result in increasing the height and root length of the chili plant (Capsicum annum).

INTRODUCTION
Salinity causes problems for plants in saline soils because of the excessive concentration of dissolved salt in the soil, which causes water difficult to be absorbed by plants, resulting in low turgor pressure. This resulted in a deterioration in plant growth, and changes in anatomical and physiological characteristics (Yulianto et al., 2017). The osmotic pressure of saline soil is also one of the natural problems that adversely affected plant growth (Hadijah, 2014). Coastal areas would have the potential for red chili plant cultivation if it managed properly. Certain techniques are needed to improve the growth of plant crops. One way to restore fertility in saline soils used beneficial and fertilizing bacteria such as PGPR (Widawati, 2015). Plant growth-promoting rhizobacteria (PGPR) are free-living, soil-borne bacteria, which are capable of enhancing the growth of the plant either directly or indirectly (Kanchana et al., 2014;Pii et al., 2015).
These bacteria are also known to colonize plant roots actively. The roles of PGPR for plants are: 1) as a biofertilizer, PGPR can accelerate the process of plant growth through accelerating nutrient absorption, 2) as bio-stimulants, PGPR can stimulate plant growth through phytohormones production and 3) as a bioprotectant, PGPR protects plants from pathogens (Rai, 2006). PGPR includes several bacteria such as Rhizobium, Azospirillum, Azotobacter. Azotobacter sp. PSA 8 and Azospirillum sp. PSA 10 was known capable of synthesizing growth-promoting hormone or phytohormo ne such as Indole Acetic Acid (auxin), capable of fixing atmospheric nitrogen and dissolving phosphate. Marinococcus sp. PSA 1 was aerobic, have cocci cells, Gram-positive, irregular colony shape, and it can dissolve phosphate. The bacterium was known as saline halotolerant, which was capable of growing in medium containing 5 % NaCl (Kusumawardhani, 2018). The objectives of this research were to determaine the effect of PGPR isolates to the growth of red chili plants in saline sandy soil and to determine the best PGPR isolate is able to improve the growth of red chili plant in saline sandy soil.

MATERIAL AND METHOD Subculture
Azospirillum sp. PSA 10 was subcultured on Caceres agar medium, Azotobacter sp. PSA 8 was subcultured on Ashby mannitol agar medium, and Marinococcus sp. PSA 1 was subcultured on Pikovskaya medium. The cultures were incubated for 2 x 24 hours at room temperature (Widawati et al., 2015;Hindersah et al., 2016).

Measurement of Salinity Soil
The saline sandy soil was sampled from the Sodong beach area, Cilacap. Soil salinity was measured using a calibrated hand refractometer (Martiningsih et al., 2015;Putra et al., 2018).

Seedling preparation
The saline sandy soils were taken then dried and sifted evenly. The sandy soil was mixed with manure with a ratio of 2: 1 then sterilized in drum sterilizer. Selected red chili seeds (Panex F1 100) with uniform size were planted on the planting BioEksakta: Jurnal Ilmiah Biologi Unsoed Volume 2, Nomor 2 (2020): 261 -265 E-ISSN: 2714-8564 medium slowly and then covered with soil. The seedling that has been grown or already had 3-4 leaves or after 21-24 days were selected for the further experiment (Widayanthi et al., 2017).

Inocula Preparation
Amount of 1 loop of the culture of Azospirillum sp. PSA 10., Azotobacter sp. PSA 8 from the nutrient agar medium was inoculated to nutrient broth medium and incubated in the shaker incubator (150 rpm, room temperature) for 1 x 24 hours at room temperature. Amount of 1 loop of the culture of Marinococcus sp. PSA 1 was inoculated in nutrient agar medium with streak continues method then incubated for 1 x 24 hours at room temperature. Amount of 3-4 mL of aquadest was added onto the cultures that already incubated and scraped off using drugalsky, the solutions were placed in a test tube. The amount of 1 mL solution was taken and inoculated in 20 mL nutrient broth medium. The population of bacterial inoculum was determined as many as 10 8 CFU / mL by spectrophotometric method.

Inoculation of red chili plant with PGPR isolates
Selected seedling was planted in a polybag with a diameter of 25 x 20 cm which contained saline sandy soil. The roots of selected red chili seedlings were planted in the polybag in an upright position. The amount of 2 mL of liquid bacterial isolates with a population of 10 8 CFU / mL was sprayed onto the roots in each polybag (Widayanthi et al., 2017).
This research was conducted experimentally using a Completely Randomized Design (CRD) with 8 treatments. Each treatment was repeated 3 times. The treatments were comprised of as follows:

Maintenance of Seedling
Maintenance of red chili seedling included watering and weeding. Watering plants were done in the morning and evening or at necessary by spraying water using a hand sprayer. Seedlings that are growing poorly or are not in good condition were replaced with other healthy seedlings. Weeding was done manually to control weeds. Maintenance of the seedling for 35 days in the greenhouse.

Measurement of Plant Growth
Measurement of plant height was done by measuring the height of chili plants from the base of the stem to the highest shoot using a ruler. The root length measurement was done by measuring the length of the root from the root base to the tip of the root using a ruler (Widayanthi et al., 2017).

RESULT AND DISCUSSION
The media used for the growth of red chili plants were prepared based on the results of measurements of salinity soil on the Sodong beach Cilacap. The Sodong beach soil had the salinity of 0.5 dS/m. Rachman et al. (2018); Sitorus (2012); Thohiron & Prasetyo (2012), stated that the salinity content is classified as very low if it has an Electrical Conductivity value <1 dS/m. Coastal areas usually contained saline soil because there were influenced by tides. Low salinity in coastal areas was due to natural leaching of salt by rainwater, because the sodium contained in saline soil was diluted.
The result of this research showed that the growth of red chili was significantly affected following the application of PGPR isolates especially in increasing the plant height and root length based on Analysis of Variance (ANOVA) at 5 %. This result indicated that PGPR isolates could provide nutrients for plants such as P and N and to produce phytohormone, so they can increase the plant growth. PGPR isolates used were might be able to trigger root development, so that supports absorbing more nutrients and affect plant height. Kusumawardhani (2018) reported that Azospirillum sp. PSA 10 and Azotobacter sp. PSA 8 were capable to fix nitrogen, dissolve phosphate, and produce phytohormones such as IAA, while Marinococcus sp. PSA 1 could fix nitrogen and dissolve phosphate. In addition, Azospirillum sp. PSA 10, Azotobacter sp. PSA 8, and Marinococcus sp. PSA 1 was resistant to salinity of NaCl 5 %. Iswati (2012) found that the addition of PGPR significantly affected the root length of tomato plants. A'yun et al. (2013) reported that PGPR (Azotobacter sp.) had a significant effect on the chili plant's height. The combination treatment of PGPR isolates (Azospirillum sp. PSA 10, Azotobacter sp. PSA 8, Marinoococcus sp. PSA 1) showed the highest root length and plant height of 9.4 and 14.9 cm (Table 1). This indicated that the PGPR consortium was able to stimulate the chili (C. annum) plant height. Anggarwulan et al. (2008) also found that the consortium of PGPR isolates was able to stimulate plant growth because bacterial BioEksakta: Jurnal Ilmiah Biologi Unsoed Volume 2, Nomor 2 (2020): 261 -265 consortium has an excellent synergistic correlation in the availability of N and P elements. Aiman et al. (2017) and Mukhtar et al. (2019) reported that Azospirillum sp., Azotobacter sp., and Marinococcus sp., could fix nitrogen, dissolve phosphate, and produce phytohormone thus if the plant inoculated by PGPR consortium produced better plant yield. PGPR saline-resistant bacteria can help plant growth in extreme environments to obtain the required elements such as N and P. The N element is absorbed by plant roots in the form of ammonia (NH3), but N element was available in the form of N2 in the air. The mechanism of N fixing by the PGPR bacteria was by converting N2 from the atmosphere into ammonia aided by the nitrogenase enzyme . PGPR hydrolyze organic P into inorganic forms, such as in the form of orthophosphate (H2PO4 and HPO4 2-), through the secretion of organic acid, produce phosphatase enzymes such as phosphomonoesterase enzymes and phytase enzymes which responsible for the hydrolysis of organic phosphate into inorganic phosphates. The presence of supply N and P elements as nutrients available in the soil can, therefore, help the plant growth.
Based on Least Significant Difference (LSD) analysis at 5 % of plant height and root length of red chili plant (C. annum) showed that the combination treatment of PGPR isolates showed the best result followed by Azospirillum sp. PSA 10, Marinoccocus sp. PSA 1, and Azotobacter sp. PSA 8. Kusumawardhani (2018) reported that Azospirillum sp. PSA 10, Marinoccocus sp. PSA 1, and Azotobacter sp. PSA 8 was capable of fixing nitrogen. Azospirillum PSA 10 was able to dissolve phosphate higher than Azotobacter sp. PSA8. According to Oedjijono et al. (2012), members of the genus Azospirillum sp. can fix nitrogen more dominant than other nitrogen-fixing bacteria. Widawati et al. (2015) stated that Azospirillum sp. bacteria could live and spread widely in the rhizospheric area in several soil ecosystems. Their population was higher in plant rhizosphere than other rhizospheric bacteria.
The ability of Marinococcus sp. PSA 1 in dissolving phosphate was higher than Azotobacter sp. PSA 8 (Kusumawardhani, 2018). Marinococcus sp. is moderate halophilic bacteria means that the bacterium could adapt to a wide range of salt concentrations (Shin et al., 2016). Marinococcus sp. had a metabolite that functions as osmoprotectant such as ectoine, which able to reverse the plant growth inhibition caused by osmotic stress (Rai, 2000).

CONCLUSION
Based on the results obtained, it can be concluded that PGPR isolates affected the height and root length of Chili plant in saline sandy soil. The combination of PGPR isolates of Azospirillum sp. PSA 10, Azotobacter sp. PSA 8, and Marinococcus sp. PSA 1 showed the highest result in increasing the height, and root length of Chili plants in saline sandy soil.