Abstract

• Fish sauce, salt-fermented product, is an economically important fishery product in most Southeast Asian countries. Its manufacturing processes have been conducted with various species of fish based on salt to fish ratios. In this research, the appearance and taste of fish sauce, was improved to reach the export quality product by treating with two effective methods, adsorption mechanism and high membrane technology. The characteristics of coconut coir pith activated carbon were determined and it was used as adsorbent. According to the SEM images, processed activated carbon had mesopore suitable for dye removal and micropores which were important for adsorption mechanism. The physico-chemical properties of processed fish sauce such as protein content, salt content, pH, turbidity, colour and total solids content before and after treatment by adsorption have been analyzed. Selected adsorbent, coconut coir pith activated carbon provided the colour bleaching efficiency 40.70 % and sodium chloride reducing efficiency 8.82 % in the treatment of fish sauce. After membrane filtration, turbidity and deep brown colour of fish sauce were distinctly reduced and clear fish sauce was obtained but dissolved solids that had less than (0.1 to 0.01) m pore size cannot be removed by membrane filtration. So it was obviously seen that lignocellulosic adsorbent could effectively improve the quality of fish sauce than ultrafiltration.