Avaliação do teor proteico do peixe pedra - pomadasys kaakan e corvina otolithes ruber comercializado no mercado de peixe da praia de Costa de Sol-Maputo

Abstract

The Fish, from a nutritional point of view, is a food that constitutes one of the main protein sources of high biological and energetic value. The nutritional value and quality of a fish can variety or be influenced by the way the fish is caught, the size, sex, age, species and season of the year. The main objective of this study was to evaluate the Protein Content of Fish Stone (Pomadasys kaakan) and Corvina fish (Otolithes ruber) commercialized in the Fish Market of Costa de Sol-Maputo. The samples obtained were analyzed in EMU in the Chemistry (soil moisture), soil (ash and protein determination) laboratories. The moisture content was determined by gravimetric using an oven at 105 ° C up to constant weight, and ashes by calcination of the dried and subsequent samples incinerated in a muffle at 550 ° C for 4 hours. The protein content was determined by the Micro-Kjedahl method which involved in multiplying the total nitrogen content present in the sample and by factor 6.25. The results obtained showed that fish stone has a higher protein and ash content in both sizes, small (4 - 8 cm, 28.4% protein and 3.1% ash), large (9-23 cm, 31.1% proteins and 1.4% ash) respectively. In general, it can be concluded that the levels evaluated are in accordance with the table of standard proportions of the chemical composition of fish and that the stone fish is a very protein fish compared to the corvine fish, being Corvine have in the present study high humidity. The variation of the chemical composition of the fish was influenced by factors such as species, size and feeding. The results obtained in this work may be advantageous for the consumer, not only as well as for the economy in order to better meet the demand of fish from the commercial point of view, in the area of health and nutrition, better guidance for an adequate diet.