Antioxidant capacity and flavor compounds of lily rice wine fermented with aroma-producing yeasts

To develop a rice wine with the fragrance and medicinal ingredients of lilies, aroma-producing yeasts (Saccharomyces cerevisiae H1, Hansenula sp. H3, and Pichia kudriavzevii H6) were used for the production of lily rice wine. When the amount of lily added was 1.5 g per 10 g glutinous rice, the content of flavonoids and polyphenols reached 55.54 and 67.68 mg/L, respectively. The sensory evaluation suggested that lily rice wine had the highest score for "malty", "sweety", and "fruity" when the amount of lily added was 0.5 g per 10 g glutinous rice. The result of temperature-programmed headspace gas chromatography ion mobility spectroscopy (TP-HS-GC-IMS) and headspace solid-phase microextraction gas chromatography-olfactometry-mass spectroscopy (HS-SPME-GC-O-MS) clearly showed that linalool and 3-methyl butanal, the unique aromatic compounds of lily, were only detected in fermented lily rice wine to provide flower fragrance. GC-O and odor activity values (OAVs) showed that 11 compounds including ethyl acetate, 2-methyl-1-propanol, 3-methyl-1-butanol, 2-methyl-1-butanol, 3-methylbutyl acetate, ethyl caprate, phenylethyl alcohol, ethyl caprylate, phenethyl acetate, 2-methoxy-4-vinylphenol and gamma-nonanoic lactone were indicated to be the major aroma contributors. Based on the aroma recombination experiments, they were further revealed to be the key aroma-active compounds in lily rice wine. At the same time, multivariate data analysis further revealed the correlation between sensory attributes and volatile organic compounds (VOCs) in lily rice wine. This work provides a lily rice wine with a stronger fruit aroma and higher polyphenol content.