MRE pictures
MRE pictures

1999 Military Photographer of the Year winner, "Combat Cuisine".  See more MRE pictures.

Photo courtesy U.S. Department of Defense

Introduction to How MREs Work

The saying, "An army travels on its stomach" is one of those brilliant, concise statements of fact that sums up the nature of the universe. Without food, any human being is an unhappy animal. A soldier is a human on the move and under a lot of stress, so food is vitally important to performance and survival.

Food is the human body's source of fuel. Food also provides the building blocks for the body's natural repair and maintenance processes. And there is also a very strong psychological component to food. Bad food, even if it is nutritious, does not satisfy people, and in many cases people will not eat it. Otherwise we would all be happy eating dry kibble like dogs do. Tasty, healthy, nutritious food is essential to human happiness.

Given these facts, it is not surprising that the U.S. military spends an inordinate amount of time and effort supplying food to its troops. Food for the soldiers is just as essential as fuel for the vehicles and ammunition for the weapons.

Right on the packaging, military meals state that, "Restriction of food and nutrients leads to rapid weight loss, which leads to: Loss of strength, Decreased endurance, Loss of motivation, Decreased mental alertness." Obviously food is extremely important to human performance.

In this edition of How Stuff Works you will have the chance to learn about the MRE, or Meal, Ready to Eat -- the portable meals that soldiers eat in battle. There is a lot more to feeding a soldier than you would think!

Contents of an MRE bag

What's Inside?

Imagine that you are a soldier on the battlefield. You are far from a mess tent with its portable kitchen, so you pull an MRE out of your backpack or your vehicle. You might, for example, pull out a "Chicken in Thai Style Sauce" meal. The entire meal is packaged in a heavy plastic bag. Inside the bag, you find:

  • One box measuring 8-1/4" by 4-3/4" by 3/4" inches labeled "Chicken in Thai Style Sauce". Inside the box is a flexible pouch containing an 8-ounce (227 gram) serving of chicken and sauce. This is the entrée.
  • One box measuring 7-1/2" by 4-3/4" by 3/4" inches labeled "Yellow and Wild Rice Pilaf". Inside the box is a flexible pouch containing a 5-ounce (142 gram) serving of rice.
  • One flameless heater (see next section).
  • One 1.4 ounce (40 gram) foil package of crackers.
  • One 1.3 ounce (37 gram) Nutra Fruit cereal bar.
  • One packet of spiced cider drink mix
  • One packet of instant coffee
  • One packet sugar
  • One packet salt
  • One packet pepper
  • One packet grape jelly
  • One piece chewing gum
  • One moist towelette
  • One pack matches
  • One packet toilet paper
  • One plastic spoon

All together, this meal contains 210 calories for the chicken, 160 calories for the rice, 180 calories for the crackers, 130 calories for the cereal bar and 140 calories for the drink, jelly, etc., for a total of 820 calories for the meal.

A Security Police student with an MRE.

Photo courtesy U.S. Department of Defense

How Does It Taste?

The obvious question when you're talking about food is "How does it taste?" An MRE basically tastes like any sort of food out of a can does. For example, if you have had Chef Boy-R-Dee spaghetti out of a can, that is about what the MRE version of spaghetti in meat sauce tastes like.

The Thai chicken tastes like chop suey out of a can. It has a lot of chicken, along with mushrooms, celery and red pepper in a sauce that is slightly sweet (in the same way that sweet and sour chicken sauce at a Chinese restaurant tastes sweet, although this sauce is not that strong, nor is it pink). The amount of salt is completely normal for American cuisine -- it is not overpowering, but there is enough to avoid blandness. The rice that comes with the chicken is a mixture of white rice, a little wild rice, peas and carrots and a bit of sauce. It tastes a bit dry if eaten by itself, but mixed with the chicken it is fine.

Prepared "Chicken in Thai Style Sauce"

The crackers are interesting in that they are completely intact when you unwrap them. They look, taste and chew like normal saltine crackers with slightly less salt than a normal saltine.

The cereal bar tastes like any cereal bar -- it is a normal, commercial product.

A Marine adds Tabasco sauce to flavor a breakfast MRE

Photo courtesy U.S. Department of Defense

In other words, if you grew up like a lot of Americans, eating casseroles, Hamburger Helper and lots of prepared foods out of a can or a jar, then an MRE is a completely normal, completely acceptable meal for you. If, on the other hand, you are the sort of person who prefers a salad of mixed greens with essence of cranberries effused in a vinaigrette dressing, along with a filet topped with a caramelized red onion glaze, baby carrots and angel hair pasta on the side, finishing with a strawberry sorbet and mixed fresh berries for dessert, then the MRE menu is unlikely to suit you. Of course, given all that, it is unlikely that you will enjoy any part of the military experience…






  • It is lighter.



Starkist's tuna retort pouch


Heating an MRE on a field stove

Photo courtesy U.S. Department of Defense

Flameless Heaters



A Marine demonstrates a flameless heater.

Photo courtesy U.S. Department of Defense




Chemistry Tricks

M&Ms are an example of a food product designed around the rigors of military life. The M&Ms history page describes the birth of M&Ms this way:

Who would have guessed that the idea for "M&M's"® Plain Chocolate Candies was born in the backdrop of the Spanish Civil War? Legend has it that on a trip to Spain, Forrest Mars Sr. encountered soldiers who were eating pellets of chocolate that were encased in a hard sugary coating to prevent them from melting. Inspired by this idea, Mr. Mars went back to his kitchen and invented the recipe for "M&M's"® Plain Chocolate Candies. First sold to the public in 1941, "M&M's"® Plain Chocolate Candies became a favorite of American GIs serving in World War II. Packaged in cardboard tubes, "M&M's"® Plain Chocolate Candies were sold to the military as a convenient snack that traveled well in any climate. By the late 1940's, they became widely available to the public, who gave them an excellent reception.

Food scientists are constantly looking for ways to make prepared foods last longer, work in different climates, or taste and feel better.

For example, during the Gulf War, food engineers found a way to make chocolate bars that do not melt in desert heat like normal chocolate bars do. The technique involves emulsifiers that separate the fat in the chocolate so that, even when melted, it can not flow together to melt the bar. The chocolate does not liquefy in high heat, but it still "feels" like chocolate (rather than plastic) when you chew it. Hershey released it's version of the chocolate to the general public as Desert Bars during the first Gulf war.

Another recent triumph has been bread that does not disintegrate and does not go stale even after years on the shelf. It looks, tastes and feels like normal bread, and can even be used to make things like PB&J sandwiches, but it lasts far longer than normal bread does. It is called pouch bread because it comes sealed in a protective tri-laminate pouch like MREs do.

This article hints at some of the experiments that food engineers conducted while perfecting shelf-stable bread products for the military:

The reduction of sucrose ester (SE) [because of price] and the addition of sodium stearoyl lactylate (SSL) in pouch bread were evaluated. Water activity (Aw), pH and microbiological analysis were conducted to ensure specifications were met. Parameters such as specific volume, peak-force, L-value, and sensory were measured before during and after storage. Measured parameters indicated any changes in volume, texture, crumb color, acceptability, and relative chemical stability of the proposed emulsifier system. A significant synergistic effect of two emulsifiers was shown. Replacing half of the SE with 0.25% SSL almost reduce the peak force (hardness) in half without significant changes in specific volume and L-value. Whereas replacing 75%SE with 0.25% SSL increased the peak force by 33%. This level also affected L-values, appearance and sensory attributes. Research results show the beneficial, synergism of SE and SSL exist. The optimization of these emulsifiers, allows pouch bread to have an extended shelf life---now at a reduced cost. Maintaining low oxygen levels [with oxygen scavenging packets], controlling Aw [with emulsifiers] and using tri-laminated packaging give additional quality protection.

Researchers run extensive taste tests and extended feeding tests, both in the lab and in the field, to see which meals are best received. Meals that no one likes are eliminated. This research has turned up several interesting pieces of information:

  • People like variety. The original MRE program had six entrees on the menu. Today there are 24 because people eat more when there is a lot of variety.
  • "Commercial" graphics, rather than olive drab packaging, improves consumption.
  • Name brand side items (candy, chips, etc.) and a variety of "accessories" with a meal improve consumption of the rest of the meal.
  • People like the option of hot sauce regardless of what they are eating.

See the links at the end of the article for details on this sort of research.

Recreations of Civil War era storage barrels, at Fort Macon State Park

A Little History

Nations have been fighting wars for centuries, and the food problem has always been a big one for armies on the move. Having looked at the food eaten by modern soldiers, it is fascinating to look back and see, for example, what soldiers ate during the Civil War.

At Fort Macon State Park on the coast of North Carolina there is a restored fort that served during the Spanish-American war and then the Civil War. The storeroom and kitchen are restored versions of the facilities as they would have appeared over a century ago.

As you can see, the primary unit of storage was the barrel. Meat was salted and stored, in salt, in barrels (the salt prevented bacteria from attacking the meat and preserved it). Flour, rice, coffee, etc. were stored dry in barrels. At the fort they could bake normal loaves of bread, but in the field soldiers ate hardtack -- incredibly hard, square biscuits shipped in boxes. Think of how hard a dog biscuit is and you have the general feeling of hardtack.

In the photo above, you may notice barrels labeled "sour kraut" and "pickled onions", and you may find that odd. These vegetable are anti-scorbutics -- that is, they contain vitamin C and therefore help prevent scurvy, which is caused by a lack of vitamin C. Scurvy was a big problem for soldiers and sailors for many centuries until artificial vitamin C pills became widely available.

A recreation of Civil War era food scales, at Fort Macon State Park

A typical daily ration for a soldier stationed at Fort Macon during the civil war looked like this (source: park signage):

  • Pork or Bacon, three fourths pound, or Fresh or Salt Beef, one pound four ounces.
  • Soft bread or Flour, eighteen ounces, or Hard Bread (Hardtack), twelve ounces, or Corn Meal, one pound four ounces.
  • Beans or Peas, 2.56 ounces, or Rice, 1.6 ounces, or in lieu thereof twice a week 1.5 ounces Desiccated Potatoes and one ounce Desiccated Mixed Vegetables.
  • Coffee, 1.6 ounces, or Tea, 0.24 ounces.
  • Sugar, 2.4 ounces.
  • Vinegar, 1.28 ounces
  • Salt, 0.64 ounces
  • Pepper, 0.04 ounces,
  • Sperm Candles, 0.16 ounces, or Adamantine Candles, 0.2 ounces, or Tallow Candles, 0.24 ounces.
  • Soap, 0.64 ounces.

The 1861 Military Handbook and Soldiers Manual of Information has recipes that the cooks used to prepare meals for soldiers eating together in the fort. For example:

To Cook Salt Meat for Fifty Men - Put fifty pounds of meat in the boiler. Fill with water and let soak all night. Next morning wash the meat well. Fill with fresh water, and boil gently three hours and serve. Skim off the fat, which, when cold, is an excellent substitute for butter. Soup for Fifty Men - Put in the boiler seven and one half gallons of water. Add to it fifty pounds of meat, the rations of preserved or fresh vegetables (about eight pounds of fresh vegetables; or four squares from a cake of preserved vegetables); a table-spoonful of pepper, if handy; ten small table-spoonfuls of salt. Simmer three hours, and serve. When rice is issued put it in when boiling. Three pounds will be sufficient. Skim off the fat, which, when cold, is an excellent substitute for butter. Salt Pork with Mashed Peas for One Hundred Men - Put in two stoves fifty pounds of pork each; divide 22 pounds of peas in four pudding cloths, rather loosely tied, putting to boil at the same time as your pork; let all boil gently till done, say about two hours; take out the pudding cloth and peas; put all meat in one caldron; remove the liquor from the other pan, turning back the peas in it; add two tea-spoonfuls of pepper, a pound of fat, and with a wooden spatula smash the peas and serve both.

As you can see, military food preparation and menus have changed substantially since the Civil War.

For more information on MREs and a variety of military food topics, see the links in the following section.