Kvasny Prum. 1980; 26(6): 124-126 | DOI: 10.18832/kp1980020

Effects of the concentration of dissolved gases (CO2 and O2) upon the stability of bottled beer.Peer-reviewed article

J. ŠAVEL, M. PROKOPOVÁ

Samples of microbiologically contaminated beer containing different amounts of dissolved O₂ and CO₂ were bottled and divided for subsequent laboratory analyses into 4 series (A - D) with the following concentrations of the mentioned gases: A: 0,2-0,8 mg O₂ 1^-1, 0,12-0,23 % CO_2; B: 4,8-8,4 mg O₂ 1^-1, 0,02-0,14 % CO_2; C: 6,2-15,0 mg O₂ 1^-1, 0,32-0,42 % CO_2; D: 0,7-4,1 mg O₂ 1^-1, 0,32-0,44 % CO_2. All samples were stored at 22 °C. Propagation of microorganisms was ascertained by microscopic examination. Reduction of  CO₂ concentration by 0,2-0,3 % resulted in decrease of beer stability and shorter safe storage period. Propagation of yeast reduced the storage period by 1-11 days, Whereas propagation of bacteria by 1-10 days. Concentration of dissolved O₂ in the specified limits has far less pronounced effects on microorganisms than that of CO₂. Inhibiting effects of CO₂ were confirmed by cultivating Saccharomyces uvarum in beer agar at 0,25 MPa pressure. Inhibition in wort agar, rich in nutritive substances, was less marked than in beer agar.
(In Czech, English summary only)

Keywords: microorganisms, carbondioxide, oxygen, bottled beer

Published: June 1, 1980