Investigation of sensory, chemical and microbiological effects of icing with potato, sweet potato, sugar beet and red beet peel extract on rainbow trout (Oncorhynchus mykiss) fillets during storage period (3±1ºc)

In the current study, the sensory, chemical and microbiological effects of icing with potato, sweet potato, sugar beet and red beet peel extract on rainbow trout fillets investigated during 25 days of storage. Sensory results showed that shelf life of the control group and fish fillets iced with red beet and sweet potato peel extract were 21 days, while fish filltes icing with potato and sugar beet peel extract had longer (25 days) shelf life. Treatment of fish with potato and red beet peel extract resulted in lower TVB-N, PV and FFA values. During storage periods, PV and TBA values were below 13.80 meq O2/kg and 1.11 MA/kg, respectively. Main fatty acids in fish fillets iced with potato, sweet potato, sugar beet and red beet peel extract were oleic acid (C18:1ω9), decosahexaenoic acid (DHA, C22:6ω3), palmitic acid (C16:0), palmitoleic acid (C16:1) and eicosapentaenoic acid (EPA, C20:5ω3). Oleic acid was major fatty acid found the highest levels (35%) in fish treated with red beet peel extract, whilst the highest lioleic acid was found in the red beet peel extract (20.17%) group. The highest microbial growth was found in control group, followed by fish treated with sugar beet extract. The result of the study showed that icing with potato and red beet peel extract increased the shelf life of rainbow trout and provided good quality parameters.