Umami taste in edible seaweeds: The current comprehension and perception

The fifth basic taste umami, described as the essence of deliciousness, was discovered more than a century ago in Japan, after extraction of free glutamate from dashi, the Japanese broth prepared with brown seaweed Saccharina japonica (konbu). Although umami was accepted as a basic taste in the Eastern world a long time ago, umami gained recognition in the Western world very slowly. However, as the consumer's longing for delicious food is constantly growing, umami taste can be an important choice criterion. Moreover, in recent years, there has been an increasing demand for vegetarian and vegan products and edible seaweeds are a resource that has been used in the development of new food products. Consumption of edible seaweeds is becoming popular worldwide, not only due to their abundance and unique flavors but also because of their nutritional benefits and umami taste. In this review, the basic concepts of umami in seaweeds are described. The traditional consumption of sea weeds in the Eastern world, but also the more innovative approach in Western countries, are referred. The quantification of compounds responsible for the umami taste in aqueous extracts (broths) based on edible sea weeds was reviewed. Also, the influence of seaweed conservation techniques (drying techniques applied) and extraction conditions on umami potentials have been discussed, as well as the latest studies on metabolic pathways, including the biochemical reactions between glutamate and umami receptors.