Abstract: To elucidate the formation mechanism of the taste and textural characteristics of fermented Litopenaeus vannamei during fermentation with fermented glutinous rice, this study employed high-throughput sequencing to analyze the pattern of microbial community succession and systematically examined dynamic changes in quality and safety indicators including pH, total acidity, organic acids, free amino acids, microstructure and biogenic amines. Results indicated that the pH rapidly declined as fermentation progressed. Correspondingly, organic acids accumulated markedly. Lactococcus and Pediococcus gradually became the dominant bacterial genera, and Saccharomyces and Pichia became the dominant fungal genera. Microbial metabolic activities were closely associated with changes in taste and textural properties. Sweet amino acids such as glycine and alanine gradually accumulated, reaching a total content of 623.12 mg/100 g, while arginine was degraded, reaching a final content of 18.12 mg/100 g. Under the action of lactic acid bacteria, lactic acid significantly accumulated, reaching 3 464.04 mg/kg, 14.70-fold higher than that of unfermented samples. Microbial activity induced regular changes in myofibrillar structure, reducing the hardness by 16.40% and consequently promoting texture softening, thereby improving the chewing palatability of shrimp meat. At the end of fermentation, the total volatile basic nitrogen (TVB-N) value reached 17.47 mg/100 g and the histamine content was undetectable (below 0.85 mg/kg), whereas the content of total biogenic amines increased from 75.40 to 246.85 mg/kg. Pearson correlation analysis showed that Saccharomyces was positively correlated with the color (P < 0.05) and strongly positively correlated with the rice wine-like aroma and taste, whereas Pediococcus was positively correlated with the lactic acid content (P < 0.05). In summary, mixed-strain fermentation with fermented glutinous rice simultaneously enhanced the taste and textural properties of shrimp. These findings provide a theoretical basis for the development and industrial production of dedicated starters for fermented shrimp.

Key words: Litopenaeus vannamei; mixed-strain fermentation; Pediococcus; Saccharomyces; flavor quality; correlation analysis