Microbes – bacteria, yeasts and filamentous fungi - have a decisive role in the barley-malt-beer chain. Microbes greatly influence the malting and brewing performance as well as the quality of malt and beer. A major goal of the dissertation was to study the relationships between microbial communities and germinating grains during malting.
Laitila’s research revealed that by modifying the microbial populations during malting, the brewing efficiency of malt can be notably improved. Well-characterized lactic acid bacteria and yeasts provide a natural way for achieving safe and balanced microbial communities in the malting ecosystem. She showed that the malting ecosystem is a dynamic process, exhibiting continuous change. The microbial communities consisting of various types of bacteria, yeasts and filamentous fungi form complex biofilms in barley tissues and are well-protected. Inhibition of one microbial population within the complex ecosystem leads to an increase of non-suppressed populations, which must be taken into account because a shift in microbial community dynamics may be undesirable. Laitila found some new microbial species in the malting ecosystem.
Suppression of Gram-negative bacteria during steeping proved to be advantageous for grain germination and malt brewhouse performance. Fungal communities including both filamentous fungi and yeasts significantly contribute to the production of microbial b-glucanases and xylanases, and are also involved in proteolysis. Well-characterized lactic acid bacteria (Lactobacillus plantarum VTT E-78076 and Pediococcus pentosaceus VTT E-90390) proved to be effective way in balancing the microbial communities in malting. Furthermore, they have positive effects on malt characteristics and they improve wort separation.
Previously the significance of yeasts in the malting ecosystem has been largely underestimated. This study showed that yeast community is an important part of the industrial malting ecosystem. Yeasts produced extracellular hydrolytic enzymes with a potentially positive contribution to malt processability. Furthermore, several yeasts showed strong antagonistic activity against field and storage moulds. Addition of a selected yeast culture (Pichia anomala VTT C-04565) into steeping restricted Fusarium growth and hydrophobin production and thus prevented beer gushing. Addition of Pichia anomala into steeping water tended to retard wort filtration, but the filtration was improved when the yeast culture was combined with Lactobacillus plantarum E76. The combination of different microbial cultures offers a possibility to use different properties, thus making the system more robust.
According to Arja Laitila new improved understanding of complex microbial communities and their role in malting enables a more controlled process management and the production of high quality malt with tailored properties.Further information:
Arja Laitila | VTT
New risk factors for anxiety disorders
24.02.2017 | Julius-Maximilians-Universität Würzburg
Stingless bees have their nests protected by soldiers
24.02.2017 | Johannes Gutenberg-Universität Mainz
In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport
Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...
The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.
The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...
Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...
Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".
Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...
13.02.2017 | Event News
10.02.2017 | Event News
09.02.2017 | Event News
24.02.2017 | Life Sciences
24.02.2017 | Life Sciences
24.02.2017 | Trade Fair News