Evaluation of barley protein concentrate and fish protein concentrate,made from trimmings,as sustainable ingredients in Atlantic salmon (Salmo salar L.) feeds

Barley protein concentrate (BPC) was tested as a protein source in the diets of Atlantic salmon post‐smolts. Fish were fed one of four experimental diets consisting of a fish meal/soya protein concentrate control (CT) along with two feeds supplemented with increasing levels of BPC replacing the more costly SPC. A fourth diet partially replaced FM in the high BPC diet with a liquid fish protein concentrate (FPC) made from fish trimmings. No significant differences were observed in terms of growth at the end of the 12‐week feeding period, although the protein efficiency ratio (g gain g^?1 protein consumed) was significantly lower for the control compared to fish fed diets containing either BPC only or FPC and BPC. This suggests that diets containing BPC had a beneficial effect when compared to the control diet. Furthermore, the lack of any detriment to fish growth in diets containing BPC suggests there are no significant issues regarding any negative effects of potential antinutritional factors which can otherwise be the case with other plant origin products. The data presented in this study indicate that BPC and FPC are products which could be of benefit to salmon culture, and related species, in providing a valuable new raw material to the industry.     

Chemical and Organoleptic Comparison of Fish Sauce Made from Cold Water Species and Typical Thai Fish Sauce

ABSTRACT

Organoleptic and chemical properties of fish sauce made experimentally from the four cold water fish species–Arctic capelin, Atlantic herring, Atlantic cod and blue whiting–were compared with three first grade commercial fish sauces made from tropical anchovies. Although the flavor of the fish sauces made from cold water species were judged as inferior to the flavor of the tropical fish sauces, the blue whiting and Atlantic herring sauces obtained fair ranking. Chemical analyses revealed that sugar had been added in all the three commercial sauces. Although sugar is added during blending just before bottling, flavor enhancing chemical reactions, between amino groups and reducing sugars, probably occur during storage of the final product. Accordingly, this procedure should be adapted also in preparation of fish sauce from cold water species.     

Protein Hydrolysate from Visceral Waste Proteins of Bolti Fish (Tilapia nilotica): Chemical and Nutritional Variations as Affected by Processing pHs and Time of Hydrolysis

The main objective of the current work was to evaluate the proximate chemical composition and nutritional quality of amino acids of protein hydrolysates from viscera of Tilapia nilotica fish. The results of amino acid composition showed that all hydrolysates contained sufficient and/or excessive amounts of both essential and nonessential amino acids, with appreciable values of essential amino acid/nonessential amino acid ratio (0.77 to 1.59) and essential amino acid/total amino acid ratio (43.35 to 61.35). All protein hydrolysates had a high content of the flavor enhancer amino acids. The lowest values of essential amino acids were found for phenylalanine and methionine with chemical scores ranging from 0.04 to 0.77 and 0.09 to 1.06, respectively, except for 18 h hydrolysates. The protein efficiency ratio had values greatly exceeding 2.0, which is considered a high quality. On the other hand, the levels of sugar and ash contents ranged from 2.69 to 3.32 g L^?1 and 0.48 to 2.1%, respectively, with 9.2 to 14% dry matter. Mineral composition showed that sufficient amounts of calcium, sodium, potassium, magnesium, and iron were present. The results suggest that the studied hydrolysates are appropriate for use in balanced human or animal diets.