Quality changes during cod (Gadus morhua) desalting at different temperatures

BACKGROUNDTo advise consumers and manufacturers regarding decreasing the time needed to desalt salted cod (a time-consuming process), there is a need to develop knowledge about quality changes at different desalting temperatures. The objective of this work was to evaluate the physico-chemical, microbiological and sensory quality changes and their causes during cod desalting at 5, 10 and 15 degrees C, using a cod/water ratio of 1:9 without water changes. The influence of slices with different thickness and different desalting times was also evaluated. RESULTSDesalting promoted a decrease in the levels of total volatile basic nitrogen, thiobarbituric acid reactive substances and free amino acids nitrogen (FAA-N). The highest FAA-N values were found in thicker' samples desalted at 15 degrees C due to the higher proteolytic bacteria number observed in these samples, which activity compensated the leaching of soluble components to the desalting solution. The water uptake and the salt leaching out of the muscle found during the processes created conditions for the bacterial growth, contributing to the spoilage at 15 degrees C. Based on fresh odour and off'-flavours results, thicker' samples desalted at 15 degrees C after 72 h were close to spoilage and on microbial levels were spoiled. CONCLUSIONIn order to extend the shelf life and safety of cod desalted products, desalting at temperatures above 10 degrees C is not advisable. (c) 2014 Society of Chemical Industry