Shelf-stable sandwiches approved for Meal, Ready-to-Eat
Pepperoni stick and barbecue chicken pocket sandwiches have been approved for the Meal, Ready-to-Eat (MRE).
The shelf-stable sandwiches were first developed by the Department of Defense Combat Feeding Program at the U.S. Army Soldier Systems Center (Natick) in the mid-1990s as a ration to enhance soldier mobility. They require no refrigeration or freezing, utensils or heat source before consuming, although they can be warmed with a flameless ration heater.
“What this gives us is something unique,” said Dan Nattress, project officer. “We’ve combined shelf-stable bread that now supplements the MRE with meat into a lightweight, identifiable, eat-out-of-hand food.”
Shelf-stable sandwiches are comparable to Hot Pocket sandwiches found at the grocery store in size, calories and appearance, but the major difference is in the processing that allows the food to meet the Combat Feeding Program’s minimum shelf life requirements of 3 years at 80 degrees F or six months at 100 degrees F.
Military rations are commonly stabilized through thermal processing in retort pouches, but heat tends to destroy the flavor and texture of the sandwiches, said Michelle Richardson, also a project officer.
Instead, the sandwiches are developed using intermediate moisture technology. Products using this technology are preserved by controlling water activity and acidity levels. Humectants, which are substances that promote water retention, help lower water activity by reducing the amount of water available for bacteria growth. The pH or acid levels are controlled by choosing low-acid ingredients or incorporating natural acids into the product.
The amount of oxygen in contact with the food is also controlled by including oxygen scavenger packets. The sandwiches are packaged in tri-laminate pouches to prevent the transmission of water and oxygen, both necessary for the growth of yeast mold and bacteria.
“The combination of meat with the bread with differing water activities and pHs makes both safety and acceptability a concern,” Richardson said. “The water activity of the different components needs to complement each other. If the water activity of the meat is too high, you may get soggy bread.”
She said the shelf-stable sandwiches were acceptable to soldiers who tried them, and they meet Food and Drug Administration requirements for food safety.
The sandwiches are being further developed and commercialized under a Cooperative Research and Development Agreement with GoodMark Foods, Inc. in Raleigh, N.C. By partnering with industry, production costs should decrease while opening the opportunity for sales in areas such as vending machines for anyone who wants a lightweight, nutritious meal that requires no preparation or silverware, said Nattress.
Other varieties under consideration are a pizza pocket with Italian sausage and pepperoni slices in a tomato sauce, sliced beef in a barbecue sauce, tuna or chicken salad, ham and cheese, and peanut butter and jelly.
“Just about any variety you can make with a Hot Pocket you can make with this,” Nattress said.
The same technology is being applied to a new program in combat breakfast foods.
“The number of breakfast items available to the warfighter is very limited and not highly acceptable,” Richardson said, who’s leading the research. “The investigation of inter-component films and coatings may allow the use of ingredients previously impossible due to moisture or fat migration.”
Some concepts that Richardson has proposed are cream cheese-filled bagels with and without fruit fillings, sausage and cheese biscuits, breakfast burritos with bacon and eggs in a tortilla wrap, and breakfast pizza. Prototypes are scheduled to be ready this year with production planned for 2004.