SU1221243A1 - Method of producing citric acid - Google Patents

Description

- one

The invention relates to industrial microbiology, in particular to the production of citric acid by the microbiological method.

The aim of the invention is to reduce the duration of the process, increasing the yield of the target product.

It was established that the production rate when using citric acid, Achromobacterium bacteria strain depends on the initial content of hydrol in the medium and reaches a maximum at a hydrol concentration of 8-12% (optimally 10%) (Fig. 1). An increase or decrease in the hydrol concentration results in a decrease in the acid production rate.

The acidity of the medium also affects the production rate of citric acid, which is maximum at a pH of the culture fluid of 5.5-6.0 and decreases as the acidity of the medium increases. Therefore, it was proposed to conduct the fermentation process at a pH of 5.5-6.0, which is achieved by the constant introduction of milk of lime into the cultivation medium in quantities sufficient to maintain this pH value.

At the same time, this combines the fermentation stage with the citric acid precipitation stage.

Compiled by N .. Afanasyev Editor M. Nedoluzhenko Tehred O. Gortvay. Proofreader V. Sinitska

Order 1553/34

Circulation 490

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Rauschska nab, 4/5

Branch PIP Patent, Uzhgorod, st. Project, 4

43

The drawing shows the curves of the rate of production of acid with different initial content of hydrol in the environment.

Example. The fermentor is placed nutrient medium of the following composition, g / l:

K NR040,8

, 2

(NH4), 5

Trace elements 1.0 ml Hydrol 100.0 (10% of

masses among)

pH of medium 6,8-7,0

Daily culture of the strain Arhr. 182 A delicatulus is seeded at a final concentration of 10 th year in a millimeter. Sterile air is supplied at a rate of 2.5 l / min: (t 26-28 ° C). After 5 hours of cultivation, when the acidity of the medium reaches 5.5, the milk of lime begins to be fed into the fermenter at a rate that ensures the pH in the medium at the indicated level. Calcium citrate is formed as a precipitate, which is removed after 3 days after the end of fermentation. The end of the fermentation is established by the complete consumption of the carbon source and the increase in pH. The yield of citric acid is 7 g / l compared to 4.3 g / l in the known. The processing time is reduced 2.5 times.

Subscription

Claims (1)

METHOD FOR PRODUCING LEMONIC ACID, including fermentation of carbon-containing raw materials with microorganisms and precipitation of citric acid with milk of lime, characterized in that, for the purpose of Ukraine and Russia (72) Yu.S. Babenko, M.3.Serebryanaya and G.I. Tyrygina (53 ) 661.734.1 (088.8) (56) USSR Copyright Certificate No. 510508, class. C 12 P 7/48, 1976. US patent No. 493479, CL. C 12 P 7/48, 1975. to reduce the duration of the process and increase the yield of the target product, carbon is used as a carbon-containing raw material, hydrol is a waste of starch and starch production, in an amount of 8-12% by weight of the medium, while Achromobakter delicatulus 182 A is used from microorganisms, ί and milk of lime is served in the fermentation process in an amount sufficient to maintain a pH of 5.5-6.0.