Investigation of Different Regimes of Beer Fermentation with Free and Immobilized Cells

  • Ivan Petelkov Department of Wine and Beer Technology, Technological Faculty, University of Food Technologies, 26 Maritza Blvd., 4000 Plovdiv, Bulgaria
  • Vesela Shopska Department of Wine and Beer Technology, Technological Faculty, University of Food Technologies, 26 Maritza Blvd., 4000 Plovdiv, Bulgaria
  • Rositsa Denkova-Kostova Department of Biochemistry and Molecular Biology, Technological Faculty, University of Food Technologies, 26 Maritza Blvd., 4000 Plovdiv, Bulgaria
  • Georgi Kostov Department of Wine and Beer Technology, Technological Faculty, University of Food Technologies, 26 Maritza Blvd., 4000 Plovdiv, Bulgaria
  • Velislava Lyubenova Institute of Robotics, Bulgarian Academy of Sciences, P. O. Box 79, 1113 Sofia, Bulgaria

Abstract

Three different kinetic models – Monod’s model, Monod’s model with substrate inhibition, and Monod's model with substrate and product inhibition were developed for studying of beer fermentation with free and immobilized cells at different main fermentation and maturation temperatures. The most accurate model was Monod's model with substrate and product inhibition. It showed that maturation temperature had no effect on primary metabolism but it affected significantly the secondary metabolites production. In regard to carbonyl compounds and esters, the increase in maturation temperature led to different trends for free and immobilized cells. Regarding the higher alcohols, the increase in maturation temperature resulted in increase in their yield coefficients for both immobilized and free cells. A sensory evaluation of beers produced with free and immobilized cells were also carried out and the results showed similar results for two beer types.

Keywords: beer fermentation regimes, kinetic of fermentation, modeling, immobilized cells
Published online
2019-12-31
How to Cite
[1]
Petelkov, I., Shopska, V., Denkova-Kostova, R., Kostov, G. and Lyubenova, V. (2020). Investigation of Different Regimes of Beer Fermentation with Free and Immobilized Cells. Periodica Polytechnica Chemical Engineering. 64, 2 (2020), 162-171. https://doi.org/10.3311/PPch.13845.
Section
Articles