ANCHORAGE - If successful, a pilot project to make surimi from squid could eventually change the industry. A process called pH shifting has the promise of dramatically increasing yield from conventional methods that lose 30 percent to 40 percent of the soluble protein through the washing of whitefish.
Surimi, the top export from the Alaska pollock fishery to Japan, is made from grinding and washing muscle tissue, often from fish by-products, into items such as imitation crab legs and fish sticks. The industry is under increasing pressure for source material from the fishmeal and fish oil industries, thanks to the global expansion of aquaculture as well as efforts to fatten up fillets through more efficient capture of the fish weight.
Conventional washing methods leave the main muscle and connective tissue, while pH shifting retains all of the protein except for the connective tissue, according to Tyre Lanier, North Carolina State food science professor.
Lanier said even by recapturing the soluble proteins, conventional yield maxes out at about 60 percent while pH shifting can yield 85 percent to 90 percent. Other important promises of pH shifting are improved gelation - the solidification of the finished product - without using additives.
If successful, Lanier said the pH shifting technology could be marketed to companies building new surimi processing plants, particularly in Asia where the Chinese have rapidly expanded into the industry and brought down equipment costs.
New species beyond squid such as catfish or carp could also be targeted for surimi production, especially if industry moves toward aquaculture as a means to cultivate fish for surimi.