Alaska Sea Grant’s seafood technology specialist, Chris Sannito, had a busy spring and summer keeping up with a number of food processing and safety projects. In addition to offering regular classes and workshops on seafood safety, quality control and product development, Sannito regularly responds to requests for assistance with food safety and processing questions. It is a public service that the Kodiak Seafood and Marine Science Center (KSMSC) is able to provide using its state-of-the-art research kitchens and food labs designed to test products and experiment with new techniques.
Sannito worked with Noble Ocean Farms to test seaweed samples using KSMSC’s water activity meter and verify that they are dry enough to be shelf stable. For another project, the Alaska Department of Environmental Conservation referred the Orca Cannery in Cordova to Sannito for assistance with a study of their new fish smoking oven. The study used sixteen temperature probes placed throughout the oven to look for cold spots, which informs where to place product probes during smoking to ensure that the oven is always heating food at temperatures that maintain food safety and that are required by law.
A highlight for Sannito this spring was a visit to JBT Corporation in Erlanger, Kentucky, where he learned about a technology called high-pressure processing (HPP).
The HPP technology is a post-packaging process that uses extreme pressure to significantly reduce bacteria and pathogens, like E. coli and listeria, allowing packaged food to remain safe to eat and shelf stable longer. Alaska Sea Grant was awarded a grant from the USDA to explore using this technology for processing Alaska mariculture products.
The technology works by filling a chamber with water, then creating pressures of up to 88,000 pounds per square inch–far more pressure than is found in the deepest trenches in the ocean. The process doesn’t sterilize the food but damages any live bacteria that are left after packaging. “What’s so great about this technology is that it doesn’t cook the food or use any chemical processes, so it doesn’t alter the taste or nutritional content,” explained Sannito. High pressure processing can extend the shelf life of a product up to six times.
The JBT Company is one of only three main world-wide producers of this technology. Sannito said visiting the manufacturing plant where these HPP units are assembled was fascinating. “There’s this thin steel band wrapped around a cylinder that creates the ability to withstand these great pressures. If you stretched that band out in a straight line it would be 173 miles long,” he said.
The device has special pumps, or concentrators, that produce these extreme pressures. It’s enough pressure to create diamonds from graphite and has all different kinds of applications in multiple industries. “So far, it has mostly been used for things like fruit juices, avocados, and fresh pet foods,” said Sannito.
The HPP equipment is expensive, but it could make a huge difference for the marketability of Alaska grown mariculture products like packaged, fresh seaweed. “Currently, we don’t have a great way to process fresh seaweed so that it can last very long,” explained Sannito. “You can steam blanch it or dry it. But, adding high pressure processing could triple the shelf life.”
In addition to touring the facility and learning about the technology, Sannito was able to put some packaged mariculture products through the HPP process. After 60 days, Sannito will compare those items to a control product and report on the results.