Effect of whey protein coating on physico-chemical properties of gutted Kilka during frozen storage

The a im of th is paper was to study the effects w hey pro t e in c oat i ng on ch e m ic al a nd physic al properties of gut t ed K i l ka dur i ng f roz en stor a ge. Coating of Kilka has done by dipping in whey protein solution with different concentrations of 3, 7, 10 and 13%, for 1h. Then, after being packed in polyethylene dishes, they were covered in cellophane blanket and stored in -18°C. There were 125 testing and control packages, each of them weight 250grams. Heme iron, peroxide value, protein, lipid and pH has measured after 0, 1, 2, 3 and 4 months storage in freezer. R e s u l ts of h e me iron, p e roxi de v a l ue and lipid of control tr e at m ents h a ve s hown s i gni f icant difference among ex p e r i m ent al tr e at m ents (p0.05). Our results showed that coating process with di ff e r e nt whey pro t e in con c entrat i on leads to decrease in peroxide value and increases the iron content. 13% whey protein concentration was provided the most satisfactory results

Effects of different concentrations of sodium alginate as an edible film on chemical changes of dressed kilka during frozen storage

The aim of this study was to investigate the effects of sodium alginate edible coating with concentrations of 0/25, 1/25, 0/75 and 1/75% (W/V) on chemical changes of dressed Kilka during frozen storage. Prepared samples of Kilka fish have been coated for 1 h with the dipping method. Coated and uncoated samples have been packed in polyethylene dishes with selphon coverage (75 packs of 250 g). Chemical parameters (moisture, ash, protein, TVN and lipid) were examined in frozen storage at -18ºC for 4 months. SPSS Statistical Software was used for data analysis, using One Way ANOVA test. Significant reduction was found (P<0.05) in moisture value with increase of sodium alginate concentration during the study. Significant differences were found in TVN values during the third and fourth months but there were no significant differences (P<0.05) in ash and protein content. The highest content of TVN was found in control samples and use of sodium alginate edible coating affected the reduction of TVN, prevented the lipid oxidation, increased the shelf-life of Kilka and reduced the moisture