Flavor assessment of a lactic fermented vinegar described in Japanese books from the Edo period (1603–1867)

Aims: Rice vinegar is a traditional fermented seasoning in Japan, and its production remained unchanged for over 800 years until the Edo period. However, based on the available information regarding rice vinegar production methods from this period and the results of reproduction experiments, we speculated that unlike the modern-day acetic fermented vinegar, rice vinegar produced during the Edo period was lactic fermented. Main methods: To verify this assumption, we analyzed the flavor components of Honcho, a lactic fermented product prepared using a method described in books, including ''Honchoshokkan'' from the Edo period, by capillary electrophoresis/time-of-flight mass spectrometry, high-performance liquid chromatography, gas chromatography mass spectrometry, and taste sensor analysis. Sensory evaluation was also conducted to assess validation as a seasoning. Results: Honcho contains 2 % lactic acid, which gives it its acidity, and small amounts of other nonvolatile acids, but significantly lower levels of acetic acid (0.188 ± 0.015 g/100 mL, p