No abstract

ABSTRACT. This study aimed to elaborate and characterize meals containing waste from processing of tilapia, tuna, salmon and sardine for human consumption. Carcasses of tilapia and salmon, tuna torsos without fins and sardine tails were cooked, pressed, milled and dehydrated, resulting in waste meal. Greater protein (83.28%) and lower mineral matter (5.31%) were observed in tuna meal. Salmon meal presented greater content of lipids (18.81%) and sardine meal, lower content (3.98%). Tilapia meal presented greater mineral matter (37.66%), calcium (9.37%) and phosphorus (6.08%). Higher content of iron was observed in sardine and tuna meals. Higher amounts of fatty acids from n-3 series were found in salmon (53.71 g kg ). Concerning amino acids, glutamic acid showed greater proportion in all meals, followed by lysine, leucine, glycine and aspartic acid. All meals presented high biological and nutritional values and are regarded as important sources of calcium, phosphorus and iron.Keywords: waste reuse, Nile tilapia, salmon, tuna, sardine.Elaboração de farinhas de resíduos do beneficiamento de peixes para alimentação humana RESUMO. Este estudo objetivou elaborar e caracterizar farinhas de resíduos do beneficiamento da tilápia, atum, salmão e sardinha para consumo humano. Carcaças de tilápia e salmão, troncos de atum sem nadadeiras e caudas de sardinha foram cozidas, prensadas, moídas e desidratadas, resultando nas farinhas. Maior proteína (83,28%) e menor matéria mineral (5,31%) foram observados na farinha de atum. Farinha de salmão apresentou maior teor de lipídeos (18,81%) e a de sardinha, menor teor (3,98%). Farinha de tilápia apresentou maior matéria mineral (37,66%), cálcio (9,37%) e fósforo (6,08%). Observou-se maior teor de ferro nas farinhas de sardinha e atum (121,95 e 106,38 mg kg ). No perfil de aminoácidos, o ácido glutâmico apareceu em maior proporção em todas as farinhas, seguido pela lisina, leucina, glicina e ácido aspártico. Todas as farinhas apresentaram alto valor biológico e nutricional, sendo boa fonte de cálcio, fósforo e ferro.Palavras-chave: aproveitamento de resíduos, tilápia-do-Nilo, salmão, atum, sardinha.

Tilapia, salmon, tuna and sardine meals were prepared to develop and analyze extruded snacks with residue meal from fish processing. Residue meals were included in five types of corn snacks: control (0% fish meal) and four with 9% tilapia, salmon, tuna and sardine meals. Although moisture, lipids and carbohydrates rates did not differ among the snacks, protein rates increased with the increment of fish meal, reaching 11.85% in the tuna snack. Tuna and sardine snacks had the highest iron levels. The most abundant fatty acids were linoleic, oleic, palmitic, linolenic and stearic acids, with sardine, salmon and tuna snacks presenting the highest values of n-3 series fatty acids. Greater luminosity rate was reported for salmon snack, followed by tilapia, tuna and sardine snacks. The highest sensory acceptance index was verified in tilapia (78.07%) and salmon (72.40%). A 9% addition of residue meals of tilapia, salmon and tuna improved the nutritional value of the snacks.

-This study was conducted to determine the digestible lysine requirements of Nile tilapia fingerlings. Fish (n = 300; average initial weight = 1.44 g) were distributed 15 300-L aquariums, in a completely randomized design with five treatments and three replicates, and fed extruded diets containing 11.3, 13.7, 16.1, 18.4 or 20.8 g/kg of digestible lysine. The arginine:lysine ratio was maintained at 1.3:1. All fish were fed diets containing 281 g/kg of digestible protein and 3,372 kcal digestible energy/kg, hand-fed until apparent satiation. There was no effect of the dietary lysine levels on survival rate, or protein and ash body rates. With increasing levels of lysine in the diet, a quadratic effect on weight gain, feed conversion, protein efficiency ratio, protein deposition rate, deposition rate of fat, body moisture and body lipids was observed, where the best values of the variables were estimated at 15.96, 16.4, 14.35, 15.21, 15.87, 15.21 and 16.29 g/kg of lysine, respectively.The digestible lysine requirement of Nile tilapia fingerlings is 15.21 g/kg (5.41 g/100 g of digestible protein), in diets balanced for the arginine:lysine ratio.

Threonine is the third-limiting essential amino acid in diets based on cereal ingredients. A 4-week trial was conducted to determine the threonine requirement of large Nile tilapia based on fish growth, feed efficiency, body composition, protein and amino acid retention. Six hundred fish (563.3 AE 15.1 g) were distributed into twenty 1.2-m 3 cages. Five diets containing 288 g kg À1 of crude protein, 12.7 MJ kg À1 of digestible energy and 8.9, 10.5, 12.2, 13.7 and 15.4 g kg À1 of threonine were elaborated. Fish were hand-fed five times a day to extruded diets. Significantly, differences in growth performance and amino acids retention among the treatments were observed. Fish fed 10.5 g kg À1 of threonine showed higher daily weight gain, gutted weight and fillet weight (P < 0.05) compared to fish fed with other experimental diets. Diets containing 8.9-15.4 g kg À1 of threonine did not affect whole body and muscle proximate composition. Based on second-order regression analysis, the dietary threonine requirement estimated based on final gain, fillet weight and fillet yield was 12, 12.1 and 11.5 g kg À1 diet, respectively. The dietary threonine requirement for maximum fillet yield of Nile tilapia was estimated to be 11.5 g kg À1 .