Aproveitamento do resíduo de filetagem da tilápia do Nilo para produção de farinhas com potencial aplicação na alimentação humana

Nile tilápia is one of the most commonly produced fish species in the world, but its industrialization process is low yielding large quantities of waste that need to be better exploited. The objective was to promote the use of residues from the processing of Nile tilápia for the preparation of flours, characterizing them from a nutritional, oxidative and microbiological stability point of view and promoting their application in products intended for human consumption, such as French bread. Three experiments were carried out. In the first experiment (Experiment I) three flours with head, carcass and mechanically separated meat (CMS) of Nile tilápia were elaborated. These were evaluated for yield, microbiological, chemical and physical quality. In the second experiment (Experiment II), CMS flours stabilized with BHT, tea-green and resveratrol at 0.02, 0.06 and 0.1% concentrations were prepared and without antioxidant in order to characterize and evaluate lipid oxidation of flours, during an accelerated shelf-life test at 60oC. In the third experiment (Experiment III) four formulations of French bread were elaborated with increasing levels of Nile tilápia carcass meal (0, 5, 10 and 15%). The loaves were evaluated for their chemical composition, technological quality and sensorial profile. The results of Experiment I revealed that head and carcass meal presented higher yields than CMS. In the centesimal composition, were found mean values for protein of 50.3%, 56.6% and 79.0%, lipids of 4.6%, 7.2% and 13% and ashes of 38.4%, 32.6% and 4.3%, respectively for head, carcass and CMS flours. Also the predominance of oleic fatty acids; palmitic, linoleic and amino acids; glutamic acid, leucine, lysine and glycine were observed. Chromaticity component L * ranged from 77.19 to 55.32, a * from 4.44 to 4.88 and b * from 4.13 to 9.51. There was a variation of 366?m to 986?m in the Mean Particle Size Diameter (DGM) of the flour particles. In experiment II, it was possible to observe that the centesimal composition of the CMS flour did not change during the shelf-life (p> 0.05) indicating values of 8.51%, 74.84%, 12.61% and 4, 04%, for moisture, protein, lipids and minerals, respectively. Flour colorimetry was not influenced by treatments or time in the oven (p> 0.05), obtaining averages for the L * component of 52.07, a * of 4.67 and b * of 8.89. The pH (7.2) and the water activity (0.375) decreased during the shelf-life (p 0.05) for the peroxide index and for the TBARS between the control treatment and the antioxidants tested at any of the concentrations during the 60oC oven test, whose minimum and maximum values were 10 and 45 meq.kg-1 and 1.59 to 2.95 mg MDA.kg -1. In the experiment III, the addition of the levels of 0, 5, 10 and 15% of meal of tilápia carcasses in loaves, linearly decreased the moisture and carbohydrate content (P 0.05) by inclusion levels, however, 15% of Nile tilápia flour resulted in a higher amount of polyunsaturated fatty acids (4.63%) in relation to bread without inclusion (4.46%). It was observed a linear increase (P 0,05) indicando valores de 8,51%, 74,84%, 12,61% e 4,04%, para a umidade, proteína, lipídios e minerais, respectivamente. A colorimetria das farinhas, não foi influenciada pelos tratamentos ou pelo tempo em estufa (p>0,05), obtendo médias para o componente L* de 52,07, a* de 4,67 e b* de 8,89. O pH (7,2) e a atividade de água (0,375) diminuíram durante a vida-de-prateleira (p0,05) para o índice de peróxido e para o TBARS, entre o tratamento controle e os antioxidantes testados em nenhuma das concentrações, durante o teste em estufa a 600C, cujos valores mínimos e máximos obtidos foram de 10 e 45 meq kg -1 e 1,59 a 2,95 mg MDA.kg-1. No experimento III, a adição dos níveis de 0, 5, 10 e 15% de farinha de carcaças de tilápia em pães, diminuíram linearmente os teores de umidade e carboidratos (P0,05) pelos níveis de inclusão, porém 15% de farinha de tilápia do Nilo acarretou em maior quantidade de ácidos graxos poli-insaturados (4,63%), em relação ao pão sem inclusão (4.46%). Observou-se aumento linear (P