To evaluate the differences in the volatile compound profile of dark and pale beers fermented by different strains of brewer's yeast, gas chromatography with flame ionization detection and gas ...chromatography mass spectrometry analysis of eight beers was carried out. The prevalent group of compounds in all the beers analysed were alcohols (56.41-72.17%), followed by esters (14.58-20.82%), aldehydes (8.35-20.52%), terpenes and terpenoids (1.22-6.57%) and ketones (0.42-1.00%). The dominant higher alcohols were 2-methylpropan-1-ol, 3-methylbutanol, phenethyl alcohol, among aldehydes furfural, decanal, nonanal, and among esters ethyl acetate, phenylethyl acetate and isoamyl acetate. Beers fermented by the top-fermenting yeast Saccharomyces cerevisiae var. diastaticus had the highest volatile content. The addition of dark malt in wort production process had no effect on the total content of volatiles, but for some beers it caused changes in the total content of esters, terpenes and terpenoids. Variations in the total volatile content between beers fermented by different yeast strains are mainly due to esters and alcohols identified. Sensory analysis of beers allowed us to identify the characteristics affected by the addition of dark speciality malts in the production of wort and yeast strains used in the fermentation process.
Technique of malting legume seeds is not currently widespread among scientists as well as industrial maltsters. However, this method of seed modification is successfully used by humankind for ...millennia to improve technological parameters, as well as change taste and aroma of various food products. Three lentil cultivars (black, brown and green) were malted (steeped, germinated for three various time periods and then kilned) to produce nine lentil malts. Malting had significant influence on the volatile composition of lentil seeds. Total concentration of volatiles in the green lentils increased and decreased in the case of black and brown lentils after malting procedure. However, most importantly, in every lentil cultivar the contribution of various groups of compounds (such as aldehydes, alcohols, terpenes or ketones) to the overall volatilome was changed due to the malting procedure.
Bertoni is a plant native to South America that has gathered much interest in recent decades thanks to diterpene glycosides, called steviosides, which it produces. These compounds are characterised ...by their sweetness, which is 250-300 times higher than saccharose, and they contain almost no caloric value. Stevia is currently also grown outside the South American continent, in various countries characterised by warm weather. This research aimed to determine whether it is viable to grow
plants in Poland, a country characterised by a cooler climate than the native regions for stevia plants. Additionally, the impact of adding various dosages and forms of nitrogen fertiliser was analysed. It was determined that
grown in Poland is characterised by a rather low concentration of steviosides, although proper nitrogen fertilisation can improve various characteristics of the grown plants. The addition of 100 kg or 150 kg of nitrogen per hectare of the field in the form of urea or ammonium nitrate increased the yield of the stevia plants. The stevioside content can be increased by applying fertilisation using 100 kg or 150 kg of nitrogen per hectare in the form of ammonium sulfate. The total yield of the stevia plants grown in Poland was lower than the yield typically recorded in warmer countries, and the low concentration of steviosides in the plant suggests that more research about growing
in Poland would be needed to develop profitable methods of stevia cultivation.
The aim of this study was to analyze whether it is possible to brew beer without using cereals so that the produced beverage could be easily accessible for the population suffering from celiac ...disease and other gluten-related disorders. Green lentil seeds were malted and then mashed using a congress mashing procedure to assess their advantages and disadvantages in the brewing process. Based on the congress mashing procedure, the mashing process needed to produce beer was developed, and beers were produced from the lentil malts germinated during malting for 96 h, 120 h and 144 h. It was possible to produce beers from the lentil malts; however, they were characterized by a lower alcohol content, lower degree of attenuation and some discrepancies between the concentrations of various volatiles (such as acetaldehyde, ethyl acetate, and 1-propanol) compared to the control beer produced from barley malt.
In the recent years, beer brewers are experimenting with using various substrates, other than traditional barley malt, water, hops, and yeast for beer production, because new adjuncts to the beer ...brewing can add new sensory and functional properties to this beverage. Novel potatoes with purple or red-colour flesh are a good and cheap starch source and are rich in bioactive components, which could increase the nutritive value of the produced beer. The aim of the study was to determine whether some part of barley malt can be replaced by the potatoes of purple-colour flesh and assessment of properties of such beer. Beer samples showed increased antioxidant activity, higher concentration of anthocyanins and polyphenol compounds, as well as modified composition of volatiles and lower ethanol content. Beer produced with the addition of 30% of purple potatoes showed acceptable organoleptic qualities in the sensory analysis.
This study was performed to determine the possibility of using mango fruit (
) in brewing technology. The aim of using the SPME-HS-GC-MS technique was to assess what changes occurred in the volatile ...composition of mango beers brewed in this study. Mango fruit was added to the beer in five different forms to ascertain what kind of preparation should be used to improve beer aroma. Analysis of the volatile components in mango beer showed that beer without mango addition was characterized by the lowest content of volatile compounds (1787.84 µg/100 mL). The addition of mango fruit increased the concentration of compounds, such as α-pinene, β-myrcene, terpinolene, α-terpineol,
-β-ocimene, caryophyllene, and humulene, in beer. Beer prepared with mango pulp addition was characterized by the highest concentration of volatile components from mango beers (2112.15 µg/100 mL). Furthermore, beers with mango addition were characterized by a higher polyphenol content (up to 44% higher than control beer) and antioxidant activity than control beer and were evaluated by a trained panel as having a better taste and aroma than beer without fruit addition.
The goal of this study was to analyse, whether malting technique (consisting of seed hydration, germination and drying) can be used to modify concentration of various isoflavonoids in soybean seeds. ...Seeds of three soybean varieties were germinated by different lengths of time (from 24 to 120 h) and dried by two different methods, typically used to produce so-called 'light' and 'caramel' malts. It was determined, that malting decreases concentration of 7-O-β-D-glucosides such as daidzin, genisitin and glycitin, while at the same time increasing concentration of aglycones (daidzein, genistein and glycitein). Increasing time of the germination period increased concentration of aglycones. 'Caramel' type malts were characterised with higher concentration of most of the isoflavonoids (daidzin, daidzein, genistin, genistein and glycitein) than 'light' type malts. Results of this study suggest that soybean malts can be an interesting substrate in the production of various food products with increased aglycone content.
Raffinose family oligosaccharides (RFOs) are sugars, which are considered anti-nutritional substances, which are not digestible by human gastric enzymes and can lead to flatulence. Legume seeds are ...often rich in these compounds, which can be cumbersome for many people, such as vegetarians or the population of developing countries, whose diets consists of large amounts of these food products. In this study, simple procedures used around the world in the brewing industry (malting and mashing) were used to determine, whether these processes could be applied to popular legume seeds (lentil and bean) to reduce the RFOs content. Acquired malts and worts were characterised by radically decreased concentration (up to 90%) of most ubiquitous RFOs, such as raffinose and stachyose.
Wheat malts are necessary to produce wheat beers. In this study, wheat was grown with addition of seed meals into the soil, to determine whether such agricultural practice could improve the quality ...of the grain and, therefore, improve the quality of wheat malt produced from these grains. It was determined, that malt produced from the grains of the winter wheat cultivated with the use of seed meals is characterised with improved technological properties, such as saccharification time, filtration time and extract content and some of the seed meals had a positive impact on the content of various volatile compounds present in the produced malts.
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