Effect of different concentrations of pure and mixed salt on sensory and microbial quality of salted rainbow trout (Oncorhynchus mykiss) roe during refrigerated storage

Salted roe was prepared from rainbow trout (Oncorhynchus mykiss) by adding food-grade pure and mixed NaCl (3.5, 4.5 and 5.5 %) to obtain optimal concentrations of both salts. Chemical, sensory and microbiological and color analysis were measured throughout the storage time to determine the changes that took place at 4°C and to evaluate the effects of the salt type up to 60 days. Total aerobic and psychrophilic microflora, mold and yeast were determined. Microbial population was lower in products with higher salt contents (4.5 and 5.5%). The decrease due to higher pure salt content of 4.5 to 5.5% was not significant. However, the addition of 4.5 and 5.5% pure and mixed salt at these levels did to inhibit total aerobic microflora growth at 4◦C and counts reached 5 to 6 logs CFU/g at 30 and 60 day, respectively. L* value of samples increased by increasing salt concentration of 3.5 to 5.5%. All of the salted roe significantly (p