Lorena Batista de Moura

Digestible methionine + cystine requirement for Nile tilapia from 550 to 700 g

This trial was conducted to determine the dietary digestible methionine + cystine requirement of Nile tilapia (550 to 700 g) based on the ideal protein concept. Six hundred fish were distributed in a completely randomized design with five treatments and four replicates, with 30 fish per experimental unit. The fish were fed diets containing approximately 262 g of digestible protein/kg, 3,040 kcal of digestible energy/kg and 7.90, 9.40, 10.90, 12.40 or 13.90 g of methionine + cystine/kg. The fish were hand-fed three times a day until apparent satiation for 30 days. No effects of dietary methionine + cystine on feed conversion ratio, daily protein deposition, whole body moisture, fillet moisture, crude protein, ether extract and ash, plasmatic HDL and LDL cholesterol were observed. Dietary methionine resulted in a linear increase in whole body protein and linear reduction in lipid deposition rate, hepatosomatic index, whole body ether extract and ash, plasmatic total cholesterol, plasmatic total lipids and plasmatic triglycerides. According to the Linear Response Plateau, the daily weight gain and fillet yield increased up to a level of 9.00 and 9.90 g methionine + cystine/kg of diet, respectively. The digestible methionine + cystine requirement of Nile tilapia is 9.00 g/kg for weight gain and 9.90 g/kg for fillet yield, corresponding to methionine + cystine:lysine ratios of 0.60 and 0.66, respectively.

Extruded snacks with the addition of different fish meals

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.

Addition of different tuna meal levels to pizza dough

O objetivo deste trabalho foi desenvolver massas de pizza com diferentes niveis de inclusao de farinha de atum (Tunnus spp.). Para a producao da farinha de atum, foram utilizados troncos de atum sem nadadeiras, cozidos por uma hora, prensados, moidos e desidratados por 24 horas a 60 °C. Foram elaboradas massas de pizza sem inclusao (0%) ou com inclusao de 5, 10, 15 e 20% de farinha de atum, sendo estas inclusoes calculadas com base na quantidade de farinha de trigo. A farinha de atum e as diferentes massas foram analisadas quanto aos teores de umidade, proteina bruta, lipideos totais, cinzas e carboidratos, alem do valor calorico e do perfil de acidos graxos. Analises microbiologica e sensorial foram realizadas nas massas de pizza. A crescente inclusao de farinha de atum resultou em aumento do teor de proteina bruta (10,89 a 18,94%), de lipideos totais (4,63 a 5,89%) e de cinzas (2,54 a 3,54%) nas massas, sem influenciar no teor de umidade e no valor calorico. A inclusao de farinha de atum aumentou linearmente a quantidade de acidos graxos da serie n-3 nas massas, com aumento de 1,56 para 5,93 g/kg, em 20% de inclusao de farinha de atum. A relacao entre acidos graxos poli-insaturados e saturados da farinha de atum e das massas variou entre 1,21 e 1,85. A analise microbiologica demonstrou que as massas foram produzidas em condicoes adequadas de higiene. Observou-se que a inclusao de 5 a 20% de farinha de atum na massa de pizza nao interferiu significativamente (p>0,05) nos parâmetros de aroma, sabor, impressao global e intencao de compra. Concluiu-se que a inclusao de 5 ate 20% de farinha de atum e eficaz para melhorar o valor nutritivo e o perfil de acidos graxos de massa de pizza.