Effects of freezing on the chemical characteristics and on the amino acid composition of fillets automatically processed from Amazonian fish

Abstract

The objective of this article was to assess the influence of refrigerated storage on the chemical characteristics and amino acid composition of fillets automatically processed from the following species of Amazonian fish: aracu (Schizodon fasciatum), jaraqui (Semaprochilodus spp.) and mapará (Hypophthalmus edentatus). The fillets were industrially processed and stored at -30^o C for 120 days. The chemical and nutritional composition of the samples was analyzed based on their contents of: humidity, protein, fat, ash, nifext fraction and amino acid profile. After characterizing the chemical and nutritional aspects of the species, jaraqui and aracu were classified as semi-fat; they also showed the contents of protein and callories observed in other studies on freshwater fish. Mapará was considered a fat species and showed lower protein contents. It was observed that the contents of essential amino acids are responsible for an average of aproximately 42.51% of all the amino acids in the fillets of the species analyzed. Storage time did not influence their quality or composition of amino acids. This study suggests that the species analyzed are promising and likely to show a high added value. Furthermore, their technological and nutritional characteristics tend to remain stable, even under prolonged freezing.