Effects of modified atmosphere packing over the shelf life of sous vide from captive pirarucu (Arapaima gigas)

- The anaerobic bacteria counts in modified atmosphere samples remained lower limits.
- The N-TVB, TBARS, color and sensorial analyses determinated the rejected of products.
- In this research, the changes of concentration gases follow the relation CO2 > O2 > N2.
- Multiple Factor Analysis showed that shelf-life of sous vide of pirarucu is 49 days.

The goal of this study was to evaluate the effects of modified atmosphere in packing sous vide of pirarucu in tucupi and shrimp sauce under refrigeration. Three treatments were carried out vacuum at 98%, 60%CO2/40%N2, and 70%CO2/30%N2. The composition of CO2 and N2 was monitored along with evaluation of pH, aw, water retention capacity, acidity, texture, N-TVB and TBARS, color, mesophilic and psychotropic anaerobes, presence of Salmonella spp, sulphite-reducing Clostridia, counts of coagulase-positive Staphylococci, coliforms at 45 °C and sensorial analysis. All results were compared through ANOVA, Tukey's test, Principal Component Analysis and Multiple Factor Analysis. We observed a trend towards the reduction of CO2 in packages while O2 has increased by the end of storage. The microbiological results were within the established limits by law during the entire period. The shelf life of sous vide stored could be defined by N-TVB, TBARS, b* and C*, general acceptance, texture and flavor in 49 days of storage.Industrial relevanceThe development of sous vide with freshwater fish is an alternative for a value-added product to be supplied to market niches. Employing the sous vide technique on fish yields a product with better color, taste, texture, and nutrient retention than the traditional cooking processes, which makes it an attractive alternative for its consumption. This study aimed to prepare sous vide using captive pirarucu, tucupi and shrimp and to analyze the microbiological, physicochemical and sensory quality parameters during refrigerated in atmosphere modified packaging storage. The results of this study establish the product's shelf life (49 days) and contribute to defining processing and storage conditions for fish sous vide.