Use of nanocapsules carrying astaxanthin from Haematococcus microalgae coated by maltodextrin-sodium caseinate as a substitute for sodium nitrite in formulation of common sausage and evaluating microbial and texture properties of the product

In the present research, after extracting astaxanthin from Haematococcus microalgae and nanoencapsulation it with maltodextrin-sodium caseinate combination coating, carrier nanocapsules with different ratios replaced sodium nitrite (limit of 120 mg/kg) in the sausage formulation. Then, the microbial (Count of mesophilic, psychrophilic, enterobacteriaceae, lactic acid and pseudomonas bacteria) and tissue properties of the formulated sausages were evaluated and compared during the storage period (28 days at refrigerator temperature). The results showed that the treatments that were formulated with ratios of 1 (30 mg/kg) to 3 (90 mg/kg) and 1 (60 mg/kg) to 1 (60 mg/kg) of nanocapsule to sodium nitrite (C and D) have the same efficiency in terms of the ability to inhibit the growth and proliferation of bacterial groups compared to the treatment of 120 mg/kg (A) of sodium nitrite and in the all of storage period, the minimum count of bacteria is related to these treatments. The treatment containing 90 mg/kg of nanocapsules and 30 mg/kg of sodium nitrite (E) had the same ability as treatments A, C and D in inhibiting some bacterial groups until the middle of the storage period. Also, the count level in the treatment containing only nanocapsules (120 mg/kg, B) was significantly lower than the control. The results of measuring the texture characteristics of the treatments showed that the effect of nanocapsules carrying astaxanthin on increasing the water holding capacity of sausages and also reducing of cooking loss, hardness, gumminess, chewiness and tissue cutting is more than sodium nitrite. Springiness, cohesiveness and porosity indices of sausages formulated with different proportions of nanocapsules and sodium nitrite had no significant difference (p>0.05) and were more favorable than the control. In the following, it was found that the texture indicators of the formulated treatments (unlike the control) did not change significantly during the storage period (p>0.05).