Optimization of Low Salt Perilla Shrimp Paste and Analysis of Its Volatile Flavor Compounds

This study developed a low-salt Perilla shrimp paste by combining traditional preparation with the addition of yeast strain co-fermentation using oriental white shrimp and Perilla as raw materials. The effects of Perilla addition, salt addition, fermentation time and inoculation amount of koji seeds on the formula of low-salt Perilla shrimp paste were studied utilize the optimal process prediction obtained from Box-Behnken and make adjustments to the predicted process conditions based on actual production conditions. The results showed that the co-fermentation with yeast could effectively reduce the amount of salt added. The results indicated that the amount of shrimp added was fixed at 300 g. The sensory evaluation of the low-salt Perilla shrimp paste prepared under the conditions of 35% Perilla addition, 10% salt addition, and 3.5% yeast inoculation was 87.94 under the conditions of fermentation time of 5 d at 32 ℃. Its relative content of volatile flavor substances reached 97.82%, including 6 esters, 11 alcohols, 9 acids and 5 aldehydes. The contents of amino acid nitrogen, salt, protein, moisture and ash all met the requirements of SC/T 3602-2016 industry standard. Among them, the salt content was 106 mg/100 g, which was lower than the requirement of GB/T 23789-2009 national standard for salt content not higher than 120 mg/100 g. Compared to products in the market, it featured low salt and high protein content. The formulated products in this study are low-salt foods. It combines the freshness and flavor of shrimp paste with the slightly pungent and sweet aroma of Perilla.