Microbiological activity in the ground under hop and microbiological influence of blooms on the microorganisms in the beer
2002
Petrov, S.
The aim of this research is the analysis of the microbiological activity in the surrounding and rhizospherous ground under hop, as well as the analysis of the hop extract influence on the microorganisms that cause damage in the brewing industry. The research result were the followings: The number of the microorganisms in the ground has statistically significantly varied, depending on research year and sampling place. The number and activity of the ground microorganisms groups have on average been higher in the rhizospherous ground. Apart from fungi, the number of the other microorganisms groups has been higher at the end of vegetation period. The number of microorganisms has been higher in the ground where Robusta hop strain has been grown. The number of microorganisms in the beer depended on the sort of beer and time of the exposure to the outward influences. The lowest number of microorganisms has been in fresh beer and it has increased with the increase of standing time. Becoming stale, the beer proved to be the favourable culture media for the growth of harmful microorganisms. The hop extract has not inhibited yeast and Bacillus growth, while the highest extract concentration obtained from the Robusta strain inhibited the growth of Lactobacillus spp. kind.
显示更多 [+] 显示较少 [-]