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The use of purpose-selected wheat in brewing is limited because it is either not suitable for the application of usual agrotechnical measures or, more often, is not adapted to specific climatic conditions. As unmalted wheat in brewing can cause process problems and problems with the quality composition of mash/wort and consequently beer, by using the appropriate type and variety, but also by adjusting the malting process, these problems can be completely avoided or significantly reduced at the start. Two varieties were selected for the research, which in previous research showed good brewing/malting properties and which have significantly different starting values for the share of total protein (TP) in the grain. The goal of this research was to determine the effect of grain milling granulation on the quality of mash obtained from a hard type of wheat, i.e., the changes in the fermentable and non-fermentable extract ratio during mashing. Varieties with higher and lower initial contents of total protein (TP) in the grain were tested. It was found that regardless of the initial difference in TP concentration, the concentrations of total soluble proteins (TSP) and high molecular protein fraction (HMW N) are similar for varieties with higher and lower initial TP and that the difference in initial TP concentrations is shown as a difference in the concentration of insoluble protein fractions, which are eliminated during fermentation. By increasing the milling granulation in both kinds of wheat, there is a significant increase in the medium molecular protein fraction (MMW N), which is more pronounced in wheat with a lower starting concentration of TP, even though the starting concentrations of TSP in fine (Ø 0.2 mm) and the superfine milling (Ø < 0.2 mm) were similar. A significant drop in fermentability at the superfine granulation of the grain was noted. [ABSTRACT FROM AUTHOR]

Hemp contains specific secondary metabolites, the cannabinoids, which have numerous positive effects on human and animal health. Due to the dioecious nature and cross-pollination of the species as well as population varieties, different phenotypes often occur within a variety. In our study, different phenotypes were determined based on visual traits within the selected variety Carmagnola selected (CS) and the Finola selection. The cannabinoid profile in the selected samples was determined based on 10 different cannabinoids using HPLC (High-Performance Liquid Chromatography) technology. The data were statistically analyzed and it was found that the highest content of the cannabinoid CBD-A was found in the phenotypes of the Finola selection (6.36 - 6.59%), the highest CBG-A content was in the CI phenotype (1.62%) and the highest THC-A content was also in the CI phenotype (0.91%). Using principal component analysis (PCA), we found that the CS variety and the Finola selection differed from each other. However, based on the average phenotypes and analyzed cannabinoids within the variety, only CS phenotypes were distinguishable. According to the total cannabinoid content and the ratio between THC and CBD, it was concluded that the CI phenotype can be classified as chemotype II, while all other chemotypes can be classified as chemotype III. The Finola selection phenotypes had the highest overall CBD content (6.18 - 6.42%). [ABSTRACT FROM AUTHOR]

Hemp (Cannabis sativa L.), one of the oldest plants used by humankind in the world, in addition to the main group of secondary metabolites - cannabinoids, also contains the second most important group, namely components of essential oil. The synthesis of these components occurs in glandular trichomes, mostly in the female flowers of hemp plants. In our research, we examined 11 different phenotypes within three different varieties of industrial hemp (CS, Tiborszallasi, and Finola selection), based on the content of essential oil (EO). Phenotypes were determined based on the visual characteristics of individual plants. Using the GCFID method, we identified 8 main EO components and conducted statistical analysis ANOVA and PCA. The CI and CII phenotypes of CS variety differed significantly in the content of monoterpenes and sesquiterpenes. The content of myrcene was highest in the TI phenotype (29.9 rel. %), the content of α-pinene was highest in the TIV phenotype (11.9 rel. %), the highest content of β-caryophyllene was in the CI phenotype (21.3 rel. %), and the highest content of α-humulene was in the CI phenotype (8.8 rel. %). Through PCA analysis, we were able to separate individual varieties based on the average contents of component of essential oils across all three varieties and distinguish phenotypes within the CS variety. Analyzing individual varieties, we could also distinguish only the phenotypes of the CS variety, while phenotypes within the other two varieties could not be separated. [ABSTRACT FROM AUTHOR]

Hops are an indispensable ingredient in beer, and the differences in their chemical composition impart the various tastes and aromas associated with different beers. However, during storage, hops undergo changes in their chemical composition. Here, the changes in aroma and bitterness of kettle-hopped beers were evaluated in an experiment conducted on three different hop varieties (Aurora, Celeia and Styrian Wolf) with five different hop storage index (HSI) values (0.3–0.7). Hops were added to boiling wort for 5, 45 and 90 min. Alpha-acids, iso-alpha-acids, humulinones, bitterness units and hop aroma compounds in the samples were chemically analysed. All samples also underwent sensorial analysis. The old hops were not problematic in terms of bitterness or early hopping time. However, later additions of old hops reduced the quality and intensity of the hop aroma. The limit value for use without negative consequences for kettle hopping was set at HSI 0.5 for Aurora and Celeia and HSI 0.6 for Styrian Wolf. [ABSTRACT FROM AUTHOR]

Featured Application: The results of the research should help in the application of wheat with a transitional (marbled) type of endosperm texture as a raw material for brewing purposes. Wheat of medium hardness with marbled endosperm (transitional form between hard and soft wheat) in which glassy and floury zones alternate, form almost exclusively available assortment for brewing needs in Southeastern Europe. The aim of this work is to establish the influence of the grain texture and the degree of milling on the attenuation limit of wheat wort obtained from this type of wheat. Wheat worts using hard, soft transitional, or marbled endosperm texture were produced. The indicators of proteolysis, cytolysis, and amylolysis were determined, with regard to the parameter attenuation limit (AL) or fermentability. From the results for the tested parameters, it was established that despite similar starting values for the most important quality parameters, transitional wheat produces significantly different wort, both among themselves and in comparison with hard and soft wheat, and also when looking at the results for different milling degree (fine or coarse). The obtained values for the attenuation limit for transition wheat are similar or even better when compared to soft wheat, with satisfactory values for almost all examined quality parameters of wort. It can be concluded that a transitional type of wheat can be used just as well as unmalted raw material for the production of wort, as well as a raw material for malting. [ABSTRACT FROM AUTHOR]

The antimicrobial activity of hop extracts obtained from different hop genotypes were investigated against Staphylococcus aureus and Lactobacillus acidophilus. In this study the pure xanthohumol, purified β-acids rich fraction, as well as α-acids with β-acids rich fraction were used to test antimicrobial activity against Staphylococcus aureus and Lactobacillus acidophilus; whereby, the antimicrobial activity of different hop extracts against Lactobacillus acidophilus was studied for the first time. Microbial susceptibility to purified hydroacetonic extracts from different hop varieties was investigated by the broth microdilution assay to determine the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC). The hop hydroacetonic extracts were more effective against Staphylococcus aureus than against Lactobacillus acidophilus. Strong inverse correlations of MIC and MBC values were obtained with xanthohumol, cohumulone, n+adhumulone, colupulone and n+adlupulone contents, suggesting that the identified chemical hop compounds are directly responsible for antimicrobial effects. Moreover, the effect of the growth medium strength on the MIC values of hop extracts against Staphylococcus aureus was systematically investigated for the first time. The current study also reveals the effect of different hop extracts on Staphylococcus aureus, which responds to their presence by lag phase extension and generation time prolongation. [ABSTRACT FROM AUTHOR]