Application of E-tongue, E-nose, and MS-E-nose for discriminating aged vinegars based on taste and aroma profiles

The combined approach of E-senses was undertaken to discriminate the taste and aroma profiles of aged vinegars, including Chinese Shanxi extra aged vinegar (EX, 5-8 years), Japanese black vinegar (BL, 1-5 years), and Italian balsamic vinegar (BA, 8-25 years). The principal component analysis plot for E-tongue revealed that EX, BL, and BA formed individual groups with clear distinctions. The volatile compounds detected in E-nose based on Kovats indices represented that a major component in all vinegars was matched to acetic acid, which showed a strong relationship with the aging period (R=0.8186-0.9998). The discriminant function analysis plot accompanied by the MS-E-nose indicated that more volatiles were produced during prolonged aging in cereal vinegar, whereas the aging process degraded volatile constituents in fruit vinegar. Categorization with respect to aging years was possible using both E-noses. The approach using E-senses indicated a better discrimination for distinguishing the complex sensory information in aged vinegars.