Kobsak Kanjanapongkul, Tipaporn Yoovidhya, Suvit Tia, and Pisit Wongsa-Ngasri

pp. 413 - 419

Abstract

A static ohmic heating system was developed to remove protein from fish mince (threadfin bream) washwater collected from a surimi production plant in order to improve water quality. The samples were heated under different electric field strengths (EFS, 20, 25, and 30 V/cm) until reaching the desired temperature (50, 60, and 70°C), and further held at that temperature for a certain time (0, 15, and 30 minutes). Heating the samples to 70°C resulted in a better protein removal when compared to 50 and 60°C. After heating to 70°C, the samples were centrifuged. The analysis of the supernatant obtained shows the reduction of protein, COD, BOD, TS, and TDS to 42%, 25%, 23%, 44%, and 61%, respectively. The electrical conductivity of the samples showed a linear relationship with temperature and the temperature demonstrated a parabolic relationship with heating time. EFS and holding time have no significant effect on protein removal.