Improving shelf life of calf fillet in refrigerated storage using edible coating based on chitosan/natamycin containing Spirulina platensis and Chlorella vulgaris microalgae

In the present study, edible coating based on chitosan/natamycin containing Spirulina platensis and Chlorella vulgaris microalgae were used for calf fillet in refrigerated storage. An experiment was conducted in a completely randomized design with four levels of the packaging compounds (zero, 1, 1.5, and 2%) at time intervals of zero, seven, 14, and 28 days. Meat testing included pH evaluation, thiobarbituric acid (TBA), the total volatile basic nitrogen (TVB-N), texture index (e.g., hardness, chewiness, springiness, cohesiveness, elasticity, gumminess, and adhesiveness), total microbial load, and sensory evaluation (e.g., tenderness, juiciness, flavor and overall acceptability) in three replications. The results showed that the amount of pH, TBA and TVB-N of all treatments were significantly lower than the uncoated sample during storage time (p ≤ 0.05). The greatest pH change was achieved for the control treatment, and the lowest, were observed for the T7 treatment (p < 0.05) due to the strong buffering properties of algae. The lowest values of TBA and TVB-N were recorded for T7 and T5 treatments. They were significantly increased (p ≤ 0.05) during the storage time. Furthermore, the use of coating led to increasing all parameters of texture index except hardness. The total microbial load was reduced in all of the coated samples significantly (p ≤ 0.05). Sensory evaluation results showed that overall acceptability scores were significantly higher than the control (especially T1, T5) (p ≤ 0.05). Finally, our findings confirmed that the application of 1% of Spirulina platensis, 2% of Chlorella vulgaris, 2% of chitosan, and 1% of natamycin (T5), was recognized as the best treatment.