Anderson says they have recently turned their attention to probiotics, the so-called “beneficial bacteria” that are now added to some popular foods like yogurt. From the Army’s standpoint, probiotics are of interest because they might protect soldiers from gastrointestinal viruses. But the challenge, as with other foods, is incorporating them into rations that can last for several years. “The technology hasn’t come around yet to allow probiotics, which are really live bacteria, to survive for our shelf-life requirement,” says Anderson.
The food has to be tasty, of course: after all, if the food isn’t eaten, it doesn’t provide any benefits. Some military rations, like cheese tortellini, can withstand the rigorous heat treatment required to enable them last for years and remain palatable. A cheese-and-vegetable omelette, on the other hand, proved so unpopular that it was discontinued. So the scientists at Natick go through a constant cycle of testing new processing methods, like using high-pressure instead of high-heat. This year, they will be adding several items to the military menu, particularly new gluten-free and vegetarian options.
Of all the hurdles they face, getting bakery items to be edible (and taste good) after three years in 80F heat is still proving impossible for modern food science. They have been looking at processes such as osmotic dehydration (which they use to create meat rations that taste like deli cold cuts) to prolong the life of bakery items, but without success so far.
So creating pizzas and sandwiches is still a challenge, and creating the simplest sandwich is perhaps the most difficult challenge of all. “The impossible peanut butter and jelly sandwich is something we would like to have,” says Anderson.
Peanut butter and jelly sandwiches have a military history. They were on the ration menus in World War II, some people have suggested that GIs added jelly to their peanut butter to make it taste better. This American lunch favourite is one of Natick’s most frequently requested items, but it’s also one of food science’s ultimate technical challenges. Not only does it mean keeping the bread fresh, but combining ingredients with different water contents.
One problem the researchers have experienced is that peanut butter sucks moisture out of the bread, the same way it sticks the roof of your mouth, making it dry. Another is that the water from the jelly goes into the peanut butter. Not to put too fine a point on it, this makes as Anderson puts it, “an absolute mess”.