SURVEY ON PHYSICOCHEMICAL TRANSFORMATION OF SALT-FERMENTED FISH SAUCE FROM ANCHOVY

Abstract

Fresh anchovy and salt, mixed at a ratio of 3:1 (V/V) were fermented for 8 months. The experimental results showed that the total nitrogen content was 9.75 ± 0.71 g/L after one month of fermentation, increased to 33.08 ± 0.81 g/L in the 5^th month (p ≤ 0.05) and relatively unchanged between 6^th and 8^th months (p > 0.05). The volatile basic nitrogen content appeared from the 1^st to the 5^th months and reached to 156.61 ± 3.64 mg/100mL (p ≤ 0.05), but increased slowly during the period from 6^th to 8^th months (p > 0.05). The color of the product in the 1^st month was red (L^û = 98.05 ± 0.12, a^û = - 3.32 ± 0.63, b^û = 3.50 ± 0.26) and changed into brown in the 8^th month (L^û = 65.73 ± 0.95, a^û = - 1.25 ± 0.23, b^û = 70.05 ± 0.11). The  amoniac nitrogen content was 4.93 ± 0.22 g/L and relatively unchanged between 2^th and 8^th months (p > 0.05). The volatile amoniac nitrogen content appeared from the 1^st to the 4^th months and reached to 6.41 ± 0.15 g/L (p < 0.05), but increased slowly during the period from 5^th to 8^th months (p > 0.05). The volatile NaCl content appeared from the 1^st to the 8^th months and reached to 265.15 ±  0.88 g/L (p ≤ 0.05).

Keywords: Fish sauce, total nitrogen, volatile based-nitrogen, fish sauce colour.