Kvasny Prumysl, 1981 (vol. 27), issue 7
Threshold concentrations of fatty acid esters in beer.Peer-reviewed article
J. VOBORSKÝ, M. KAHLER
Kvasny Prum. 1981; 27(7): 145-149 | DOI: 10.18832/kp1981025 
Content of esters significantly influences organoleptic properties of beer; the organoleptic equilibrium of beer can be disturbed by their higher content or by higher content of one of them. The authors have studied for several years the content of esters in the Bohemian beers; to establish the threshold perception concentrations Kp they chose five important esters. According to the significance indices IS calculated from observed maximal and average concentration in 12 % beer and from the determined threshold concentrations Kp it is possible to list the esters under study by their importance as follows: ethyl-butyrate...
Trend of the grain quality of the spring barley varieties.Peer-reviewed article
Z. VOŇKA, M. HLAVÁČ, M. HLAVINKOVÁ
Kvasny Prum. 1981; 27(7): 150-156 | DOI: 10.18832/kp1981026
Statistical evaluation of the varietal trials in the years 1958-1978 proved a significant breeding gain not only from the standpoint of yield potential of the new varieties, but also from the standpoint of quality. On the basis of the linear trends, the yield of the first two size-fraction grain and the values for modification improved most markedly; extract yield increased, too. Even though the rate of N-fertilization increased in the subsequent years, the trend of protein content remained favourable. Even though the rate of diastatic power was high, its changes were relatively rare. It was possible to classify the individual characteristics according...
Anaerobic production of volatile fatty acids in serie of homogeneously mixed reactors.Peer-reviewed article
I. ČERNOCH, D. HAĽAMA
Kvasny Prum. 1981; 27(7): 157-160 | DOI: 10.18832/kp1981027
A synthetic sucrose (50 gdm-3) medium was used for modeling the acidogenic phase of anaerobic digestion of organic material. Enrichment bacterial culture was obtained using the content of municipal anaerobic digester as an inoculum. A serie of 8 homogeneously mixed reactors modeled the piston flow. pH in whole system was kept at 6. Volatile fatty acids (VFA) were the main metabolic product (determined by GLC). The growth of bacteria followed the Andrews kinetics, but with negligible low KS for substrate limitation, so μ = μ mKP ( KP + P )-1, and VFA production rate could be expressed...
Cultivation of yeasts Candida utilis in air-lift fermentor.Peer-reviewed article
F. POTŮČEK, J. STEJSKAL
Kvasny Prum. 1981; 27(7): 161-164 | DOI: 10.18832/kp1981028
Batchwise cultivation of yeast Candida utilis was carried out in closed air-lift fermenter. Growth curves and volume coefficients of oxygen transfer were estimated at four different air velocities ranging from 1,03 x 10-2 to 4,13 x 10-2 m.s-1. At low levels of air flow and/or at higher concentration of biomass when the system was limited by oxygen, the growth curves show unambiguously the linear course. Volume coefficient of oxygen transfer grows up in the followed range with increasing air velocity. However the reached values of kLα, which range from 0,01 to 0,06 s-1, are lower than it is usual in...
The yeast flora of bottled wines indicating biological stability of finished wine products.Peer-reviewed article
E. MINÁRIK, G. VOJTEKOVÁ
Kvasny Prum. 1981; 27(7): 165-166 | DOI: 10.18832/kp1981029
Sacccharomyces bailii var. bailii was found to be the dominant component of the microflora of sweet bottled table wines. Torulopsis sp. belonging to air contaminants of bottling centers may be regarded as harmless accompanying yeasts of wines. The importance of effective prevention measures to achieve wine stability is underlined.(In Slovak, English summary only)