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
Seeing on the Quick: New Insights into Active Vision in the Brain
15.08.2018 | Eberhard Karls Universität Tübingen
New Approach to Treating Chronic Itch
15.08.2018 | Universität Zürich
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur
What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...
08.08.2018 | Event News
27.07.2018 | Event News
25.07.2018 | Event News
15.08.2018 | Physics and Astronomy
15.08.2018 | Earth Sciences
15.08.2018 | Physics and Astronomy