Fermentation characteristics and flavor properties of Hericium erinaceus and Tremella fuciformis fermented beverage

Abstract

This study evaluated and compared the fermentative and flavor properties of Hericium erinaceus and Tremella fuciformis fermented beverage (HTFB) produced by four commercial lactic acid bacteria (LAB), i.e., L. plantarum, L. rhamnosus, L. paracasei or S. thermophilus. All four strains showed the probiotic potential of utilizing Hericium erinaceus and Tremella fuciformis as fermentation substrates. Among four LAB, L. plantarum produced significantly highest concentrations of total acids (76.16 g/L), while the viable count of HTFB inoculated with L. paracasei was the highest (7.18 log CFU/mL). The contents of bioactive components such as polyphenols and triterpenoids significantly increased after fermentation regardless of the strains. The fermentation process enriched the volatile profile and reduced the unpleasant flavors such as nonanal and 1-octen-3-ol. According to the relative odor activity values and PLS-DA analysis, a total of 8 volatile organic compounds were identified as markers with odor contributions. Furthermore, the olfactory characteristics of the four beverages could be clearly distinguished by electronic nose. The electronic tongue results showed that the fermentation process increased the sourness and decreased the bitterness and astringency of the beverage, resulting in an improved taste property. The sensory evaluation finally confirmed that HTFB inoculated with L. paracasei was the most acceptable product to consumers with high overall flavor coordination. Overall, this work provided valuable information for the selection of premium fermentation strains to produce fermented edible fungi beverages with better nutritional and sensory qualities.