New harvests for gelling agent from 'long ogo'
common thickening agent in Japanese cooking is the focus of new
research in the US.
With a grant in hand, researchers at the university of Arizona developed a method to harvest the seaweed Gracilaria parvispora, nicknamed 'long ogo' by the Japanese.
"Our scientific challenge was to find a way to put the seaweed into a practical aquaculture system. People have been trying for years to grow this particular species, and they haven't been able to do it," said lead researcher Edward Glenn, a professor of soil, water and environmental science in the University of Arizona's College of Agriculture and Life Sciences (CALS).
Long ogo was once the most important edible seaweed on Hawaii's reefs but the reef populations of seaweed declined as a result of overharvesting. The reproductive plants are now protected by state law.
But the US researchers have developed a way to grow the complete life cycle of long ogo without needing to harvest starter plants from the ocean. Glenn says the sustainable system for growing fresh long ogo is unique in the United States.
A key part of the project is the hatchery where algal spores are allowed to settle onto rocks or coral chips and start growing in tanks. The rocks or chunks of coral are then given away to the local farmers on the Hawaian island of Molokai so they can start their own plot of long ogo.
According to Glenn the starter plants can be grown in a variety of places: an ancient fishpond in the ocean, a land-locked fishpond or even in the effluent runoff ditch from a shrimp-farming operation. The small plots of long ogo that are grown in the ocean release spores periodically, thereby replenishing the natural population.
Low in calories and rich in iron, calcium and potassium this red seaweed turns green when cooked, long ogo is eaten fresh and often combined with other foods. "It's crunchy and slightly salty, like a pickle without the vinegar taste," said Glenn. A $300,000 business, the researchers are currently looking for backing from the US department of agriculture to develop new markets for the product, including health care and organic markets.
Some large-scale seaweed-processing plants use harsh chemicals to extract the agar, but there is an opportunity to extract Molokai agar in gentler ways so it can be marketed as an organic product,?claim the researchers. "We can say this was grown in the pristine waters of Hawaii," said Nelson.
