Determinação do valor real de sulfitos nos vinhos tintos

Abstract

Wine is an alcoholic beverage, resulting from the fermentation of fresh, healthy grapes and mature, by means of microorganisms called yeasts, which transform the sugar of grape juice in ethyl alcohol, carbon dioxide and a series of secondary substances in varying amounts. To maintain the quality of food, whether its nutritional value or appearance, various products such as sodium metabisulfite or sodium pyrosulfite (Na2S2O5) are added to food as a preservative to prolong the life of food. The sulphurizing agents most used by the food and beverage industry are: metabisulfite and sodium or potassium bisulfite, which release sulfur dioxide (SO2) under the conditions of use. However, it is important to note that the amount of sulfites added to food does not reflect the levels remaining at the time of consumption of the product, due to losses that may occur during processing and storage. Objective of the work was to determine the value sulphites in Drostdy-Hof, Cellar-Cask, Baronne, Orla Maritima and Red wines Clos selected for the study using the Monier-Williams method; assess whether sulfite concentrations in different brands and lots differ significantly or not. You The results of the analyzes showed that the concentrations of sulfites in all wines analyzed ranged on average between 69.5 mg L-1 to 105.1 mg L-1. For the brands Orla Marítima, Drostdy - Hof and Baronne the sulfite concentrations are within the value recommended by the WHO and the Clos and Cellar - Cask brands above the value recommended by the WHO. According to the test (ANOVA) the sulfite concentrations in different wines differ significantly, the same is true between the different brands of wine.