Abstract

MENA, Sarahi; RODRIGUEZ, Leonardo  and  BARRERO, Marinela. Tuna (Thunnus thynnus) glazed with hydrocolloids as alternative of edible coatings and storaged at -10ºC. ALAN [online]. 2010, vol.60, n.3, pp.270-279. ISSN 0004-0622.

Numerous studies have been focused to natural ingredients to maintain the quality and shell life of foods. Edibles coating, biodegradable ingredients, such as hydrocolloids and proteins can be used for coating fish with the purpose to suppress changes of quality during frozen storage. At the present time several developing of edibles packing, like glaze using hydrocolloids, (gelatin, carrageen, starch), that besides acts as protective film for food, they are economic, can be ingested by the consumer without toxicity risk, help to preserve organoleptics and nutritional characteristics of the product and, being biodegradable they contribute to the conservation of the atmosphere. The objective of the present study was to evaluate the incorporation of hydrocolloids in the glazing tuna process as alternative of packing, to enhance its physical and chemical characteristics. Samples of tuna was glazed incorporating to its solutions of carrageen at 0.05, 0,1 and 0.15%, and gelatin at 0.5, 1%. The samples were shaped as square (15 cm3), frozen al -30ºC and glazed incorporating hydrocolloids submerging the sample its solutions at 0 ºC by 30 seconds and storage at -10ºC by 0, 15 and 30 days. Proximal analysis results, soluble proteins, TBA, and color showed that all the samples glazed with hydrocolloids decrease deterioration of the tuna products respect to samples glazed without hydrocolloids; concluding that glazing adding hydrocolloids protects tuna for loss humidity and delays degradation of proteins. Moreover, carrageen shows to a better performance at the concentrations of 0.05% compared with the gelatin and the starch.

Keywords : Thunnus thynnus; proteins; edible coating; tuna; hydrocolloids.