Novel processes utilized in food safety programs at both the Department of Defense Combat Feeding Directorate and the National Aeronautics and Space Administration’s (NASA) Advanced Food Technology Project were discussed at the July 2010 Institute of Food Technologists (IFT) Annual Meeting and Food Expo in Chicago. Presented at the same symposium, two commonalities emerged for these seemingly disparate environments: The loss of personnel to foodborne illness may jeopardize a mission, and food resupply is problematic at best.
The challenges for NASA are defined by time and, in a finite way, space. A spacecraft does not have enough room or power for refrigeration. All food has to be shelf stable, and it has to last a long time, because the next big mission, a round-trip flight to Mars, will take at least 2.5 years. Spearheading the effort to insure a safe, palatable food supply for this journey is Michele Perchonok, PhD, manager of both the Advanced Food Technology Project and the Shuttle Food System for NASA.
“We actually know how to make a food safe,” said Dr. Perchonok. “The problem is that as we make the food safe we are either heating it, or irradiating it, or drying it to an extent that we are likely losing some acceptability and nutrition.” And, due to power and volume concerns, refrigeration is out. “All of our food has to be shelf stable.”
Food for Mars
The goal is to achieve a five-year shelf life for food going on the Mars mission. To date, accelerated shelf life studies have shown that only a few items currently being served on the international space station were acceptable at even a theoretical three-year mark. Extending this expiration date is an art that involves formulation, preservation, packaging, and storage. The rate-limiting step in Dr. Perchonok’s view right now is packaging. “We would like to get a non-foil layer material amenable to the sterilization technology.”
Success is defined by acceptability: The food has to be not only nutritious but also pleasing. “You can’t just give them a bunch of calories and a multivitamin,” explained Dr. Perchonok. NASA research has shown that the eating experience of familiar tastes and textures, especially of favorite foods, is critical to the psychosocial health of crews on long missions.
Food During Wartime
In space you take your food with you, but in combat the method is to buy local. “We procure a lot of our [food items] right from wherever we fight,” said Andy Senecal, PhD, program advisor for the U.S. Army food safety and defense team. And food safety standards, especially in poorer countries, are of critical concern. “Enteric diseases can become a big problem and [are] actually considered the number one non-battlefield injury.”
Right now the best defense is inspection of food production facilities at the site of procurement. This strategy addresses only the cleanliness of the facility and the proper temperature of food preparation, however. “What we would like to do is give inspectors better, more rapid, field-deployable type devices where they can actually assay the product itself.”
We actually know how to make a food safe. The problem is that as we make the food safe we are either heating it, or irradiating it, or drying it to an extent that we are likely losing some acceptability and nutrition.
Michele Perchonok, PhD, NASA
Such testing is currently done in central labs with up to six weeks of turnaround time. To hasten the process, Dr. Senecal and colleagues are working on biosensor devices, polymerase chain reaction- and immuno-based assays that can be both highly portable and user friendly. Such devices exist in one form or another for use in chemical/biological warfare settings but await validation for food.