산업적으로 산도 17.0 이상의 고산도 시초를 생산하기 위하여 반연속식인 1st stage와 유가식인 2nd stage로 구성된 two stage 초산 발효를 온도 $30^{circ}C$, 교반속도 600rpm, 통기량 0.1vvm에서 실시하였다. 1st stage에서 초기 에탄올 농도를 $50.0g/{ell}$, 잔류 에탄올 농도를 $5.0g/{ell}$로 정하여 반연속적으로 초산발효를 하고, 2nd stage에서 발효시간의 경과에 따라 에탄올을 유가식으로 첨가하여 초산발효액내의 에탄올 농도를 $5.0g/{ell}$에서 $10.0g/{ell}$로 유지했을 때 산도가 17.6인 고산도 식초를 생산 할 수 있었으며, 또한 이때의 최대 초산 생산성은 $3.3g/{ell}{cdot}hr$였다.
The production of vinegar containing 16.0-18.0% of acetic acid was examined in two stage fermentation consisting of semi-continuous and fed-batch type. The optimum conditions were obtained when the fermentation was carried out at agitation of 600 rpm, aeration of 0.1 vvm and temperature of $30^{circ}C$. The initial and residual ethanol concentration in 1st stage were $50.0g/{ell}$ and $5.0g/{ell}$, respectively, and the ethanol concentration in 2nd stage was maintained from 5.0 to $10.0g/{ell}$. The maximum productivity was 3.3 gll-hr and the acidity was 17.6% after the two days of acetic acid fermentation.
