Kvasny Prumysl, 1990 (vol. 36), issue 4
Enzymic determination of ethanol in beer.Peer-reviewed article
J. KÁ©, P. PRŮCHA, T. BURIANOVÁ
Kvasny Prum. 1990; 36(4): 97-98 | DOI: 10.18832/kp1990012 
The enzymic determination of ethanol using commercial kits of Boehringer has been compared with the commonly used distillation method according to Czechoslovak standard CSN 56 0186. Samples of 8, 10, 12 % beers and low alcoholic beer Pito were analyzed. It was statistically proved that both methods corelate on significance level 99 % with the correlation coefficient 0,997. The enzymic determination is, however, advantageous in its rapidity and simplicity.(In Czech, English summary only)
Sorbic acid determination in wine using HPLC.Peer-reviewed article
B. ©PINAR, V. KELLNER, J. ČULÍK
Kvasny Prum. 1990; 36(4): 99-101 | DOI: 10.18832/kp1990013
A rapid and simple HPLC method for the determination of sorbic acid in wines was developed. The time of the determination is from 2 to 3 minutes. The isolation of sorbic acid from matrix can be performed in the column of a domestic provenience. The method is suitable for the detection of sorbic acid above 0,1 mg.l-1 and it can be used not only with wines but with other beverages as well.(In Czech, English summary only)
Production of L-malic acid by immobilized bacterial cells.Peer-reviewed article
H. KUČEROVÁ, B. ©PAČEK, J. ČERNÝ
Kvasny Prum. 1990; 36(4): 101-105 | DOI: 10.18832/kp1990014
The optimum conditions for a preparation of the biocatalyst and its application in the production of L-malic acid using the enzymic conversion of fumaric acid were studied. For the immobilization in alginate the bacterial strain Corynebacterium species from the stationary phase of growth was used. An increase of the L-malate production together with a decrease of the byproduct (succinate) formation can be affected by so called activation using a detergent. An increasing stability of immobilized cells can be achieved by drying followed by swelling in the solution of the stabilizer. Using the batch process the maximum conversion of 82 % can be achieved...
Oxygen transfer during batch culture.Peer-reviewed article
F. POTŮČEK
Kvasny Prum. 1990; 36(4): 106-108 | DOI: 10.18832/kp1990015
The oxygen transfer during batch cultivations in airlift fermenter was studied. The oxygen transfer rate moth fermenter was studied. The oxygen transfer rate was characterized with the volumetric coefficient (kLa) that has been determined by the balance method of the gas phase. The kLa values were described by correlation equations and discussed even from the standpoint of an energy consumption. Further, the growth characteristics of yeasts Torulopsis ethanolitolerans were evaluated as well.(In Czech, English summary only)