Impacts of whey protein edible coating on chemical and microbial factors of gutted kilka during frozen storage

The aim of the present study was to investigate the impact of whey protein coating on quality and shelf life of Kilka fish. Whey protein edible coating was prepared in three different concentrations, including 3, 7, 10 and 13%. Then gutted Kilkas were coated for 1h, packed in polyethylene dishes with cellophane blanket and stored at -18 °C. Total microbial count, total volatile nitrogen (TVN) and moisture evaluation were carried out within 0, 1, 2, 3 and 4 months (sample size: 75 packages, weighted 250 grams each). Results showed that there was no significant difference between total microbial count and total volatile nitrogen among samples (p>0.05). Moisture of coated samples with 13% concentration of whey protein had significant difference with other treatments (p < 0.05) suggesting that whey protein edible coating with 13 % concentrations can enhance quality and increase shelf life of Kilka fish in storage of freezing up to 4 months.