Avaliação da concentração de metabissulfito de sódio no músculo do camarão processado de forma artesanal e industrial comercializado na cidade de Quelimane

Abstract

The present study evaluated the concentration of Sodium Metabisulfite in the muscle of Shrimp processed (Artisanal and Industrial) and marketed in the City of Quelimane, with the objective of understanding whether the concentrations of Metabisulfite found in the shrimp sold in Quelimane comply with national legislation. This research was conducted using samples obtained from artisanal and industrial processors collected from March to May. The concentrations of Sodium Metabisulfite in the shrimp were analyzed using the Monier-Williams method, which involves determining the preservative by heating the sample with hydrochloric acid in an inert atmosphere. The released SO2 is collected in a 3% hydrogen peroxide solution, where it is oxidized to sulfuric acid, which is then stoichiometrically determined by titration with sodium hydroxide. The results revealed significant differences between the results of artisanal and industrially processed shrimp. In the artisanal processing, most samples showed very low or undetectable levels of sulfite, which may be related to a lack of knowledge about the importance and uniform application of the preservative. Among the samples obtained from artisanal processors, the concentration of the preservative found was 0 ppm. However, samples from industrial processors showed better results, with Metabisulfite concentrations within the limits established by Mozambican legislation, ranging from 44.3 to 103.59 ppm. Processor L exhibited higher concentrations compared to Processor K, with a minimum of 63.25 and a maximum of 103.59 ppm, while Processor K varied from 8.49 to 72 ppm, being its minimum and maximum. These discrepancies have significant implications for the fishing industry in Quelimane and for the local population. From the results obtained, it was possible to observe that there is a considerable influence of processing methods on the absorption of Sodium Metabisulfite by the shrimp, with industrial methods proving to be much more efficient than artisanal ones. Inadequate artisanal processing compromises food safety and can affect consumer health, in addition to damaging the reputation of the local fishing industry in the external market. The study highlights the need for improvements in artisanal processing methods and reinforces the importance of rigorous control over the chemical quality of shrimp, aiming not only to meet export standards but also to ensure food safety.