摘要:
A finished vinegar having an acetic acid concentration higher than 20 percent weight by volume is produced by repeating a fermentation cycle wherein a broth is fermented at 27.degree.-32.degree. C. in a 1st submerged fermentation tank by a continuous batch process, and, when the acetic acid concentration of the fermenting broth reaches 12-15 percent weight by volume, the large part of the fermenting broth in the 1st fermentation tank is withdrawn and charged in a 2nd submerged fermentation tank. The 1st fermentation tank is recharged with a mash and the fermentation of the fermenting broth in the 2nd tank is continued under aeration while lowering the temperature of the fermenting broth in such manner that the final fermentation temperature does not fall below 18.degree. C. and the lowering temperature does not become higher than the temperature once lowered.
摘要:
Vinegar having an acetic acid concentration higher than 18 percent weight by volume is produced in a submerged fermentation by maintaining the temperature of the fermenting broth after the initiation of the fermentation at 27.degree.-32.degree. C. until the acetic concentration of the fermenting broth reaches 12-15 percent weight by volume and thereafter maintaining the temperature of the fermenting broth at 18.degree.-24.degree. C.
摘要:
Vinegar having an acetic acid concentration higher than 20 percent weight by volume is produced in a submerged fermentation by maintaining the temperature of a fermenting broth at 27.degree.-32.degree. C. until the acetic acid concentration of the fermenting broth (after the initiation of fermentation) reaches 12-15 percent weight by volume. Then the temperature of the fermenting broth is lowered by 0.5.degree. C. to 2.degree. C. Fermentation is continued at the lower temperature until the concentration of acetic acid increases by between 0.05 to 2 percent weight by volume. At this time, the temperature is again reduced by from 0.5.degree. C. to 2.degree. C. The fermentation is continued, with subsequent temperature reductions of from 0.5.degree. C. to 2.degree. C. each time that the concentration of acetic acid in the fermentation broth increases by 0.05 to 2 percent weight by volume over the highest concentration found in the course of the fermentation at the preceeding temperature stage, until the desired concentration of acetic acid is obtained. However, at no time is the temperature of the fermenting broth allowed to fall below 20.degree. C.
摘要:
A method for measuring the alcohol concentration of an acetic acid fermentation broth which comprises (a) forming a sample gas containing volatile components present in the acetic acid fermentation broth, the volatile componentscomprising alcohol and acetic acid; (b) passing the sample gas through an absorption column packed with a material which binds acetic acid whereby the acetic acid is absorbed on the material; (c) passing the sample gas which has passed through the absorption column to a gas sensor for measuring the alcohol content of the gas by outputting an electrical signal which correlates to the alcohol content of the sample gas; and (d) determining the alcohol content of the sample gas in response to the electrical output signal from the gas sensor. The invention also provides a method of forming the sample gas by passing a sample of the fermentation broth through a water-repellent gas permeable tube mounted in a hollow cell and passing a carrier gas through the hollow cell whereby volatile components from the fermentation broth inside of the tube diffuse through the gas permeable tube wall and are intermixed with the carrier gas to form the sample gas containing the volatile components.