Biodegradation of surimi processing and crab canning wastewater using indigenous bacteria consortium

Abstract

Biological treatment of surimi and crab wastewater has been carried out using a consortium of indigenous bacteria isolated from the wastewater. The treatment carried out is by combining a consortium of proteolytic bacteria, lipolytic bacteria and proteo-lipolytic bacteria. The bacterial consortium was added to surimi and crab canning wastewater. The purpose of this study was to determine the optimum consortium of indigenous bacteria which can degrade protein and fat in the wastewater of surimi and crab canning. Liquid waste samples were taken from the initial sewerage of surimi processing and crab canning. Biodegradation of surimi processing wastewater and crab canning was carried out aerobically on a laboratory scale. The maximum growth rates of proteolytic bacteria were 0.020, 0.021 and 0.23 per hour, while lipolytic bacteria had a maximum growth rate of 0.0012 and 0.003 per hour. The decrease in dissolved protein content in surimi wastewater was higher than in crab canning wastewater. The dissolved protein content of surimi wastewater decreased from 11.38 to 3.28 mg/L using a proteo-lipolytic consortium, while there was a decrease of 3.19 to 2.64 mg/L in crab wastewater with the same consortium. The lipid content of crab canning wastewater decreased from 0.0623 to 0.0100 mgL using a proteo-lipolytic consortium while there was a decrease of 0.0318 to 0.0120 mg/L in surimi wastewater with the same consortium. The highest percentage of degradation in dissolved protein was 46.73% in surimi wastewater using a lipolytic bacteria consortium while in crab canning wastewater was 12.48% with the same consortium of bacteria. The highest reduction rate of lipid content was 84% in crab canning wastewater using proteo-lipolytic consortium, while in surimi wastewater was 62.28% using te same consortium. Consortium bacteria in surimi wastewater tended to degrade protein higher than bacteria in crab canning wastewater.