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Brewers commonly produce ales since the ale yeast is more resilient, ferments quicker and requires higher temperatures, which are easier to ensure as opposed to lager and pilsner, which require lower temperatures and longer lagering time. However, Kveik yeasts are also resilient, ferment at fairly high temperatures (up to 35 °C), and can provide light, lager-like beers, but more quickly, in shorter lagering time, and with reduced off flavors. Diacetyl rest is not needed. The intention of this paper was to assess the possibility of producing pseudo-lager by using Lutra® Kveik. A batch (120 L) was divided into six fermenting vessels and inoculated with Lutra® yeast. To test its possibility to result in lager-like beer at higher temperature, we conducted fermentation at two temperatures (21 and 35 °C). Fermentation subjected to 21 °C lasted for 9 days, while at 35 °C, fermentation was finished in 2 days. After fermentation, both beers were stored in cold temperatures (4 °C) and then kegged, carbonized, and analyzed (pH, ethanol, polyphenols, color, bitterness, clarity). Alongside the sensory evaluation, a GC-MS analysis was also conducted in order to determine if there are any difference between the samples.

Since food is inseparable from biotechnology, it is not surprising that food biotechnology has been included in the curriculum of the Faculty of Food Technology Osijek, University of Osijek (PTFOS) since its foundation some 50 years ago. The choice of research topics of a small core of researchers in the field of biotechnology at PTFOS, which has grown over the years, was also mainly related to food biotechnology and included the study of abiotic and biotic stress factors of crops, enzyme activities related to grain storage, the study of mycotoxigenic fungi related to food and feed safety, enzyme (bio)catalysis and the general improvement of biotechnological methods for the production of fermented foods (especially beverages, beer and fruit wine). However, the emerging need for the food industry to move to more sustainable primary production and processing systems has led to a rethinking of how resources are used within traditional food processing systems, e.g. the production residues from the agri-food industry have been recognised as a valuable resource for the production of high-value products and biofuels. This is where biotechnology and the circular economy met at PTFOS. The European Commission defines the circular economy as a model in which the generation of waste is minimised and the value of products, materials and resources is retained for as long as possible, so that what was once considered waste becomes a resource. Production residues, i.e., by-products and waste materials, from the food industry, including the same fermentation technologies that were the subject of research at PTFOS, are now being reused for the isolation of biologically active compounds, the production of enzymes, biofuels, and other valuable products, or as enzyme carriers and biosorbents. An overview will be given of the previous research topics and projects in the field of biotechnology, as well as the topics and projects related to biotechnology and the circular economy that are currently being carried out at PTFOS.

The objectives of this study were to establish the impact of Fusarium culmorum infection and fungicide treatment on the occurrence of deoxynivalenol (DON), 3-acetyl deoxynivalenol, T-2 toxin, HT-2 toxin, nivalenol, fusarenon-X, diacetoxyscirpenol and zearalenone in wheat, wheat malt and wort (beer). The concentrations of these compounds were also measured in the germ/rootlets, spent grains and spent yeast because these are the most important by-products and are further used as food or feed additives. Two wheat genotypes were obtained from the Agricultural Institute in Osijek, Croatia. The Osk.110/09 genotype, the genotype more susceptible to Fusarium infections, and Lucija, the genotype less susceptible to Fusarium, were analysed in this research. Each genotype was treated in four different ways at the field: (A) control, (B) treated with fungicide Prosaro® 250, (C) inoculated with F. culmorum spores and treated with fungicide Prosaro® 250, and (D) inoculated with F. culmorum spores. All samples were malted and brewed according to standard procedures, products and by-products were analysed for the mycotoxins by using LC-MS/MS. Since the majority of trichothecenes are polar molecules, the water after steeping was also analysed with LC-MS/MS. Mycotoxin concentrations were lower in malt samples treated with the fungicide. Elevated mycotoxin concentrations were observed in samples of both genotypes exposed to F. culmorum. Fungicide treatment was observed to suppress mycotoxin production and accumulation. However, samples with notably high mycotoxin concentrations, especially DON, retained elevated mycotoxin concentrations throughout the entire beer production process, even after a six-month storage period. DON proved to be the most frequently occurring mycotoxin in all of the by-products. The highest concentration of this compound was found in the steeping water from sample D (Osk.110/09), at 20,326 μg/l, leaving the spent grains of this sample with no detectable levels of DON.

Craft beers are characterized by a specific regional aroma that originates from raw materials, yeast, and the fermentation process. They are most often produced by the top-fermentation process or even by spontaneous fermentation. In the last decade, craft beer production and sales in the Republic of Croatia has been increasing resulting in popular brands, especially among young consumers and the female population. The increase in their consumption has been recorded in the southern, Mediterranean area of Europe more as a reflection of global, world trends, which force a specific “local” taste. However, new varieties of hops are present in craft beers in various combinations, as well as other atypical spices, and equally important larger amounts of polyphenols that change the degree and profile of bitterness. In this study, we analysed the relationship between ambient temperature (summer and winter) and the participants’ sensory preferences relating to each beer (consumers). Five different beer’s styles were analysed according to their sensory profile, and preferences (Standard Light Beer (SLB), Pilsner (PSL), Weizen Ale (WSB), India Pale Ale (IPA) and Ale Citrus Flavoured Beer (CAB)). Regarding “preference”, a panel of 40 untrained assessors was used. The most preferred style in summer was the classic PSL, and the least preferred was the CFB. Regarding the testing in the winter, the most preferred beer was also PSL, and the least preferred was a wheat ale (Weizen Ale). The most preferred style showed less bitterness and lower turbidity and polyphenol content. This study advances the understanding and complexity of the preference of different styles of craft beers in Mediterranean which has a warm climate.

During kilning, higher temperatures are employed to obtain the desired colour and aromas of malt. At higher temperatures the formation of polycyclic aromatic hydrocarbons (PAHs) in malt is a great possibility. Since PAHs are undesirable and designated as health hazards, it is important to quantify and qualify them in different malts. The European Food Safety Authority (EFSA) gave strict recommendations about PAHs in different foods, but omitted malt as a potential hazardous raw material that can cause health damage to beer consumers, the aim of this investigation was to assess the presence of 16 PAHs (naphthalene (Nap), acenaphthylene (Anl), acenaphthene (Ane), fluorene (Flu), anthracene (Ant), phenanthrene (Phen), fluoranthene (Flt), benz[a]anthracene (Ba A), pyrene (Pyr), chrysene (Chry), benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF), benzo[a]pyrene (BaP), dibenz[a, h]anthracene (DahA), benzo[ghi]perylene (BghiP), and indeno[1, 2, 3 -cd]pyrene (InP)) in different, commercially available malts (amber, black, pilsner, and cara-120). The results showed that PAHs can be detected and quantified in the analysed malts, with some in high amounts (BaA in black malt was 737 µg/kg). Minimal levels of BaA were detected in the amber malt, 60.53 µg/kg. The PAH4 (BaP, BaA, BbF, and Chry) sums are identical to the BaA concentrations in all malts and greatly exceed the EFSA prescribed levels for PAH4 in processed cereal-based foods (1 µg/kg).

Proceedings contains 13 original scientific papers, 10 professional papers and 2 review papers which were presented at "10th International Scientific and Professional Conference WITH FOOD TO HEALTH", organised in following sections: Nutrition, Dietetics and diet therapy, Functional food and food supplemnents, Food safety, Food analysis, Production of safe food and food with added nutritional value.

Najčešće identificirani mikotoksinpripadnik skupine trihotecena je deoksinivalenol (DON). Modifikacijom DON-a u biljkama nastaje njegov modificirani oblik, biljni konjugatdeoksinivalenol- 3-glukozid (DON3Glc), podložan hidrolizi probavnim enzimima u ljudskom organizmu.Time se mogu otpustiti nekonjugirane molekule DON-a čime je ponovno bioraspoloživaslobodna molekula mikotoksina. Zbog navedenog, cilj ovog rada bio jeodrediti pojavnost modificiranog oblika DON-a, DON3Glc u pivu prisutnom na tržištu Republike Hrvatske, budući da je pivo jedna od namirnica koja se proizvodi od žitarica, a u kojima je pojavnost DON3Glc očekivana. Ispitano je 12 uzoraka piva u triplikatu, 6 svijetlog i 6 tamnog, primjenom LC-MSͭMS metode. Rezultati nisu pokazali značajnu razliku u sadržaju DON3Glc između uzoraka svijetlog (srednja vrijednost 10, 3 ± 4, 37 ngmL-1)i tamnog(srednja vrijednost 9, 49 ± 3, 61 ngmL-1) piva. Međutim, vidljiva je razlika u sadržaju DON3Glc ovisno o proizvođaču piva što može biti uzrokovano razlikama u sirovini, soju kvasca te razlikama tehnološkog procesa koji se primjenjuje pri proizvodnji piva različitih proizvođača.

This paper aims to give an overview of multiple research that concern: 1) determination of starting β-glucan concentrations in different end use barley varieties (brewing, brewing/feed, feed and naked), and the changes of their concentration during malting and brewing ; 2) the influence of micromalting method and variability of malting process parameters on the measured values of β- glucans ; 3) the influence of arabinoxylans on the results (obstruction of β-glucan degradation). It has been established that the starting concentration of β-glucans in barley and malt do not correlate with the concentration of β- glucans in wort. A strong correlation has been detected only in brewing varieties (Vanesa, Tiffany). This implies that “good brewing variety” is a direct result of varieties’ genotypic properties. It has been established that the micromalting process has a huge impact on β-glucans. This makes it harder to compare the results between the same varieties determined by different research institutions. Furthermore, the degradation of arabynoxylans also has a great impact on the results because of their ability to mask the degradation degree of β- glucans. This implies that they can mask the results of the degree of degradation of β-glucans depending on the different time maximum related to these two polysaccharides.

β-Glucans are described as non-starch polysaccharides, characterized by (1→3), (1→4) β-D-glucose linkage. In human nutrition, they are regarded as extremely wanted because of their bioactive and medicinal properties. Since β-glucans comprise soluble fibres that have the ability to lower cholesterol, regulate blood sugar, reduce the risk of heart disease and colon cancer. Especially desirable are (1,3)-β-D-glucans because they act as immunomodulatory agents. The aim of this paper was to determine the mass fraction of β-glucans and the ratio of total and soluble β-glucans in barley and malt in domestic hulless barley varieties. Hulless barley is an accesible and cheap source of β-glucans. Four different domestic varieties of hulless barley obtained from the Agricultural Institute Osijek were examined. The results indicate that all tested varieties have higher β-glucans content than standard winter and spring varietes. Variety Matko showed close relation to the EFSA (European Food Safety Authority) recommendations of 750 mg of soluble β-glucans per serving.

Two wheat genotypes varying in susceptibility to infection by Fusarium species were assessed by four different treatments in the field (i) control, (ii) treated with fungicide (Prosaro), (iii) inoculated with Fusarium culmorum spores and treated with fungicide and (iv) inoculated with F. culmorum spores. Indicators of wort quality indicators (saccharification time, speed of filtration, wort colour, pH value, extract, air dried extract and dried extract values) were determined using standard methods. The results showed that that infection with F. culmorum affected wort quality, particularly wort colour and significantly prolonged (or stopped) saccharification time and speed of filtration for wheat types. Treatment with fungicide reduced the extent of quality deterioration, even with samples infected with F. culmorum. The wheat type was which was less susceptible to Fusarium infection produced less compromised worts confirming its superiority to the more susceptible wheat genotype. Further study is suggested at a commercial scale to determine the interrelationship between Fusarium infection, fungicide treatment and wheat malt quality.

The aim of this paper was to assess the damage Fusarium graminearum causes on barley grains and to determine the influence of heavy infection on alcohol content in beer. The overall results showed that the F. graminearum infection did not affect fermentation course in case of maximum 20% infection. However, Fusarium infection higher than 20% can cause significant damage to breweries and totally halt fermentation. Further research should be pointed to how different multi-toxins originating not only from Fusarium, but from other fungal genders and plant metabolites affect beer fermentation.