Carp species forms the bulk of the aquaculture production in India and studies have shown that the filleting waste of these species, particularly skin can be a good source of gelatin. This study is a comparison of the gelatins from these unexploited sources with that of mammalian gelatins to get a better understanding of their physicochemical and functional properties with respect to mammalian gelatins. The study showed that mammalian gelatins had significantly superior physical properties viz., higher viscosity, melting & setting temperature and faster setting time. The odour scores were significantly higher (P<0.05) for bovine and porcine skin gelatins (3.1-3.12), indicating that they had a distinguishable odour and hence can be considered as inferior to fish skin gelatins in organoleptic qualities. The gel strengths of rohu and common carp skin gelatins were significantly lower than mammalian gelatins. Among the carp skin gelatins, grass carp skin gelatin was found to have better compatibility with gelatin from bovine and porcine skins.

Effects of smoking duration as well as turmeric treatment on the quality characteristics of ready‐to‐cook sutchi catfish fillets during chill storage were evaluated. One lot of fillet portions was dip treated in 2% turmeric solution (w/v) and smoked at 60C for 1 h. Another lot was dip treated in 2% turmeric solution (w/v) and smoked at 60C for 2 h. Significant reductions in the free fatty acid (FFA), peroxide value (PV) and thiobarbituric acid reactive substance (TBARS) values were observed in samples treated with turmeric and smoked for 1 h (T1) and 2 h (T2) compared to their respective control samples (C1 and C2) during storage at 4C. Smoking for 2 h has significantly reduced FFA formation, but increased PV and TBARS of both control and treated samples during storage. Highest total volatile base‐nitrogen content was observed in C1 followed by C2 samples. The textural parameters showed a decreasing trend in all the samples over the storage period. Higher hardness values were observed in C2 and T2 samples compared to C1 and T1 samples. The sensory scores were found to be higher for the treated samples, among which T2 samples showed the highest overall acceptability score. The results of the present study revealed a shelf life of 7, 14, 17 and 21 days for C1, T1, C2 and T2 samples, respectively, during chill storage. Practical Applications Although synthetic additives are widely used in fish processing industry to control the process of lipid oxidation as well as microbial growth, the present trend is to decrease their use because of the growing concern about the safety of such chemical additives. In recent years, fish processing sector is giving more emphasis on the use of natural preservatives such as spices and its derivatives for improving the stability and shelf life of fish and fish products. The present study gives an account of the effects of turmeric treatment on the quality characteristics of a value‐added smoked fish product during refrigerated storage. Turmeric treatment along with extended smoking is found to be effective in delaying the spoilage process during storage. The findings of the study could be used among the processors to decide upon the appropriate preprocessing protocol for improving the quality of the product to get better profitability as well as consumer satisfaction at the retail markets.