We have the best seafood and the finest coffee. But let’s not fool ourselves. Like the rest of the country, we are actually spending less of our money on fresh, raw ingredients and more on processed convenience foods than ever before. According to the U.S. Bureau of Labor Statistics, American households now spend more on processed foods than on any other category of food—and twice as much as they did in 1982.
But the Northwest has a contribution here, too. The region has a taste for food processing technologies that are already making convenience foods fresher, tastier and longer lasting, and that could revolutionize safety in the years ahead.
Consider salmon. Locals might be able to tell the difference between Copper River sockeye and king fillets at a glance, but much of the country lives thousands of miles from fresh seafood and has to make do with canned meat and premade ready meals. “When you put a salmon fillet into a canned product and run it through a conventional thermal process, the damage is so severe you don’t see the original shape,” says Juming Tang, professor of biological systems engineering at Washington State University (WSU).
Conventional processing involves vacuum packing the food in a can or a pouch, then putting it through a pressure cooker at temperatures above 212 degrees for more than an hour to kill most of the bacteria (although some highly acid foods can make do with lower temperatures). Not only does this method alter the appearance and texture of the original food, making it drier and less appealing to the eye, but it also breaks down critical nutrients, such as the beneficial omega-3 oils in salmon.
During the past few years, Tang’s team at WSU has been developing new microwave-based technology for food preservation that addresses some of those issues. Its Microwave-Assisted Thermal Sterilization (MATS) system immerses packaged food such as salmon or pasta in pressurized hot water while simultaneously heating it with microwaves at a frequency of 915 megahertz—a frequency that penetrates food more deeply than the 2,450 MHz used in domestic microwave ovens.
This combination eliminates food pathogens and microorganisms in five to eight minutes, with far less effect on the food. “We can see texture difference, color difference and an appearance totally different from conventionally processed products,” says Tang. “And we can show a much higher retention of nutrients.”