Chemical Composition of Fish Sauces Produced in Southeast and East Asian Countries

Liquid fish sauces (n=61) collected from seven Southeast and East Asian countries were analyzed for free amino acids, organic acids, nucleosides and nucleic acid bases as well as creatine, creatinine, pH, salt content, moisture, and total nitrogen. The fish sauces were only made from fish species such as anchovy and sardine. A high nitrogen recovery of 97.9% was obtained for all nitrogen-containing compounds in a Vietnamese fish sauce. The fish sauces of Vietnam, Japan, and Thailand showed high concentrations of these compounds except for organic acids and a very close amino acid pattern whereas those of Myanmar and Laos exhibited the lowest contents and a different amino acid pattern from those of the above three countries. Korean and Chinese fish sauces showed intermediate contents and the same amino acid pattern. Of all organic acids determined, acetate dominated in Myanmar and Chinese fish sauces, suggesting that acetic acid fermentation is predominant. In the fish sauces from other countries, pyroglutamate and lactate were high. These data will give a standard for the chemical composition of fish sauces from various Southeast and East Asian countries and during the production of fish sauce. These results also indicate that creatinine which originates from creatine during fish sauce fermentation and receives only small bacterial decomposition is a possible marker for the quality control in fish sauce factories, because its determination is much easier and time saving than for the other compounds.