Fresh Picked Versus Store Bought Vegetables

When I was a kid, I used to spend Summers at my grandparents’ farm in Georgia.  I remember picking shiny green apples, ripe muscadines, persimmons, blueberries and blackberries from bushes and trees all over the property.  I also remember shucking fresh corn, picking spinach and lettuce and plucking baseball-sized ruby red tomatoes from the fields that my grandfather cultivated.  And up until I started growing my own produce, those were the best fruits and vegetables I had ever tasted.

Stored Lettuce

How Fresh Is This Lettuce?

Those in-between years were a steady diet of lackluster “fresh” produce from a grocery shelf, with the occasional treat that might come from a farmers’ market or local grower.  I knew I was getting some measure of nutrition, and the taste, while bland compared to what I remembered from my childhood days in the fields, was okay.  But, just okay.

When the idea to build the Bell Back 400 (the 400 feet of suburban farm we have developed in our backyard) popped into my head, I knew I had to make a good case for investing the time and money into the effort.  So, in my homework phase, I did some research into the quality of fresh produce versus vegetables picked, stored, shipped and piled onto a market shelf.

The science behind some of this can be intense, but I only needed a layman’s understanding, so I presented my case using leafy vegetables as an example.

Photosynthesis – Why Those Fresh Vegetables Taste So Good

A plant utilizes a process called photosynthesis to produce stored energy.  ‘Stored’ is key, as we will see.

The process of photosynthesis is essentially:

Carbon dioxide + water + light (typically sunlight) = starches and simple sugars

These sugars and starches are stored in the plant.

It is these stored sugars that actually give the vegetable it’s flavor.

It is also during the process of photosynthesis that the internal nutritious goodies (vitamins, minerals, phytochemicals, etc) are produced.

As a green friendly aside, oxygen is a byproduct of photosynthesis.  Plants and their ability to feed oxygen into the atmosphere are critical in maintaining healthy oxygen levels across the planet.

So, photosynthesis results in energy being stored in the plant.  How does the plant utilize this energy to fuel growth, flowering, and seeding?

Respiration – Red Bull For Plants

Respiration is the process a plant uses to convert the stored sugars into actual energy to fuel growth.

Stored sugars + oxygen = energy

Water is a by product of this process.  Respiration results in the energy a plant needs to grow and seed.

As you can see, photosynthesis and respiration are intertwined processes that a plant depends on for survival.

Process Interrupted – Where Did The Flavor Go?

When a plant is harvested and stored away from sunlight or artificial grow lights, the process of photosynthesis is interrupted.  This means that the plant will no longer produce stored energy, the simple sugars that provide the leaf’s rich flavor.  Production of phytochemicals and other beneficial nutrients will also cease.

Photosynthesis also depends on water.  Even if the harvested vegetables are stored under the appropriate light, without added water, photosynthesis will come to a grinding halt when the plant’s internal water content is exhausted.  This is why picked vegetables wilt quickly when left in the sun.

So, without appropriate storage conditions, photosynthesis stops.

However, as long as oxygen is present, the process of respiration will continue.  This will burn up the energy stores of the plant until there is no fuel left.  Once these energy stores are depleted, you are left with a fairly bland tasting vegetable with significantly reduced nutrition value.

However, this deterioration does not happen immediately.  Depending on the vegetable, the initial level of stored sugars, storage practices, etc., it can take any number of hours, or even days (1 or 2), for the energy stores to be fully depleted.

When I cut lettuce or spinach from the garden, it usually ends up on a plate within a few hours, if not sooner.  Even during this short storage period, I spray the leaves with water and store the produce in a clear bag in a fluorescent light lit crisper.  This ensures that all the vegetable will retain maximum flavor from the stored sugars, and the highest levels of nutrients and phytochemicals.

And yes, you really can taste the difference.

Produce On Store Shelves

When Was This Produce Harvested?

Are The Stores At Least Trying?

You’ll notice that in many markets and higher end grocery stores that the produce aisle has displays lit by fluorescent lights and built-in water sprays systems.

Knowing what we now know about photosynthesis and respiration, can you guess why?

And if you are rooting thru a stack of ‘fresh’ spinach in the local market, which bundles of greens do you think will look more fresh? The bundles on top exposed to light, or the bundles in the middle of the pile away from light?

Stores do try to extend the life of the produce they bring in, but it really isn’t even close to the taste or nutrition level of what fresh harvested vegetables offer.  How much time has gone by since those store veggies were picked?  How were they stored during transport?  How long have they been on the shelf?

Ask your local grocery store manager where they get their produce.  How is it shipped?  What is the typical time from harvest to when it actually appears on their shelves.

Then just ask yourself – how much of the original flavor and nutrition is left?


Update: 11/2014

If you liked this post, please check out our new edible gardening community:

Farming Suburbia

Whether you are growing tomatoes on your patio or have a backyard full of herbs and produce, you are Farming Suburbia.

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