Studies on the Benefits for Human Health on Fermented Seafood and the Development of Freshness Maintenance Technique of Fish

Abstract

  I and my students have developed some fish sauces made from puffer, whale and sea urchin gonad as the local specialties of Shimonoseki city in west Japan. These sauces were commercialized. Antioxidant actives of these sauces were measured by using chemiluminescence, ESR (electron spin resonance), ORAC (oxygen radical absorbance capacity) and HORAC (hydroxyl radical averting capacity) methods. As the results, these sauces indicated the high antioxidant activities. Furthermore, these sauces were researched by the next-generation food functional estimation method, i.e., the new simultaneous measurement method using cellular signal transduction mechanisms. This method means the simultaneous measurement of chemiluminescence and fluorescence by LED light indicating superoxide anion radical generation and intracellular calcium ion concentration, respectively, of neutrophil-like HL60 culture cells. It was found that some sauces indicated the anti-inflammatory activity in addition to antioxidant activity. On the other hand, I and co-researchers investigated the supply of high quality frozen raw fish by a quick freezing method using alcohol brine. The whole body of Japanese horse mackerel was used. Alcohol brine freezing at -25°C was compared with air freezing at -20°C. Quality of fish meat was analyzed using K value as an indicator of freshness by HPLC, pH, TBARS value as an indicator of lipid oxidation, remaining ethanol by GC/MS and sensory test. As the results, it was indicated that the fish meat frozen quickly by alcohol brine method was superior to that by air freezing.