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Quality Changes of Naturally Fermented Kvass During Production
Abstract and Figures
Commercially available beverages sold as kvass are kvass drinks and malt extract drinks, made by diluting grain extract concentrates with water and adding colourings, different flavours and artificial sweeteners. Kvass quality parameters are defined by the Regulation No 926/2010 Quality and classification requirements for kvass and kvass (malt) beverage of the Cabinet of Ministers of the Republic of Latvia Naturally fermented kvass is made from rye bread rusks without additional additives. The aim of this research was to assess the quality changes of naturally fermented kvass during production stages. Experiments were carried out at the Latvia University of Agriculture Department of Food Technology. Dry matter (refractometer, ISO 6496), active acidity (LVS EN ISO 10523:2012) and sensory properties (25 panellists; line scale ISO 4121:2003) were analysed in kvass samples during production stages. During fermentation stage of naturally fermented kvass, pH drops from 4.08 to 3.77 and in later production stages pH is between 3.82 and 3.88, pH levels do not exceed the index values of the Regulation of the Cabinet of Ministers. Relative dry matter content reduced from 5.96% to 4.94%. Sensory evaluation showed that the intensity of flavour, aroma and acidity was most pronounced in kvass sample C (total production time 156 h), however, colour was most pronounced in kvass sample A (total production time 36 h). Longer maturation process aids in the formation of more robust flavour as well as yeast and protein residue.
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... The pH of bottled fermented kvass (Ltd. Liepzeme) ranges from 3.77 to 3.88 in storage [8]. ...
The aim of this research was to compare the commercially available kvass concentrate to the kvass extract which was experimentally produced from the naturally fermented kvass. Dry matter was determined according to the standard ISO 2173:2003, active acidity – ISO 10523:2012, and apparent viscosity was measured with a DV-III Ultra Brookfield rheometer, using a spindle SC4-18 with the speed 50 rpm at 26.9 °C. Sugars were determined using high-performance liquid chromatography. The sensory evaluation of kvass drinks (recombined kvass concentrate and extract) was performed according to the ISO 4121:2003. The dry matter content in the kvass concentrate (Ltd. Ilgzeem) was 69 %; it was diluted with distilled water to the dry matter content 32.4 ± 0.2 % of kvass extract (made from Ltd. Liepzeme kvass). Active acidity in the kvass concentrate was significantly (p = 0.012) lower (pH 2.86) than in the kvass extract (pH 4.18). Apparent viscosity in the kvass extract was 13.68 mPa×s and in the kvass concentrate 5.22 mPa×s. Major sugars in the kvass extract were fructose and glucose and in the commercial kvass concentrate – fructose. Hedonic evaluation showed that there were no significant differences (p > 0.05) in the preference of kvass drinks. The intensity of aroma, flavour and acidity was significantly more pronounced in the kvass drink made from the commercial kvass concentrate.
The study examines the possibility of expanding the international market for low-alcohol products by modernizing the traditional probiotic drink made from grain raw materials, which is popular in Eastern Europe - kvass. In particular, it is proposed to solve this problem by developing a fundamentally new version of kvass based on orange juice, honey and spices. During the work, 5 samples were made using various strains of yeast and lactic acid bacteria. During the physical and chemical analyses and tasting evaluation of the samples obtained, it was revealed that all samples comply with the norms established in interstate standards. It is noteworthy that the samples made using the bacteria Lactobacillus acidophillus, which are usually used in the production of lactic acid products, and not in plant-based drinks, received the highest consumer rating.
In this article we provide an overview of the newest data concerning the effect of non-alcoholic constituents of alcoholic beverages, especially of beer, on pancreatic secretion, and their possible role in alcoholic pancreatitis and pancreatic carcinoma. The data indicate that non-alcoholic constituents of beer stimulate pancreatic enzyme secretion in humans and rats, at least in part, by direct action on pancreatic acinar cells. Some non-alcoholic compounds of beer, such as quercetin, resveratrol, ellagic acid or catechins, have been shown to be protective against experimentally induced pancreatitis by inhibiting pancreatic secretion, stellate cell activation or by reducing oxidative stress. Quercetin, ellagic acid and resveratrol also show anti-carcinogenic potential in vitro and in vivo. However, beer contains many more non-alcoholic ingredients. Their relevance in beer-induced functional alterations of pancreatic cells leading to pancreatitis and pancreatic cancer in humans needs to be further evaluated.
Baker's yeast is used for bread fermentation throughout the world and it is very important for the bread quality. The scope of this work was to investigate how the aroma of wheat bread crumb is influenced by yeast fermentation by comparing the aroma formation of bread fermented by seven commercial baker's yeasts. Dough samples were fermented with equal number of yeast cells to equal height and then baked. The volatile components were extracted by dynamic headspace sampling and analyzed by gas chromatography mass spectrometry. The dough fermentation time varied significantly from 40 to 100 min. The fermentation compounds 2,3-butanedione and 1-propanol were found in significantly higher concentration in bread fermented with the four baker's yeasts having the shortest fermentation times. Furthermore, 3-methylbutanal, 2-methyl-1-propanol and ethyl acetate were found in significantly higher concentration in two of the yeasts. On the other hand phenylacetaldehyde and 2-phenylethanol were found in significantly higher concentration in bread fermented with two other yeasts. It can be concluded that use of the seven commercial baker's yeasts for bread fermentation resulted in significantly different bread aroma profiles.
BACKGROUND
Traditional foods are an important part of the culture, history, identity and heritage of a region or country and are key elements in dietary patterns. In most countries there is limited information on the nutritional composition of such foods and therefore there is a need to investigate, register and promote traditional foods. One of the aims within the Sustainable exploitation of bioactive components from the Black Sea Area traditional foods' (BaSeFood) project is to generate for the first time new data on the nutritional composition of traditional foods from six Black Sea Area countries to promote their sustainable development and exploitation. RESULTSThirty-three traditional foods were analysed in an accredited laboratory to determine their nutritional composition, and the data were fully documented. The nutrient content varied widely because of the nature and variety of the analysed foods. The energy content ranged between 4 kcal per 100 g for kvass southern and 900 kcal per 100 g for mustard oil, with the exception of the analysed teas, which did not contribute to energy intake. CONCLUSION
The use of a common methodology for the study of traditional foods will enable countries to further investigate these foods. Moreover, a new nutritional knowledge base of traditional foods from Black Sea Area countries will contribute to promote local biodiversity and sustainable diets by maintaining healthy dietary patterns within local cultures.
The food and beverage industry is re-discovering fermentation as a crucial step in product innovation. Fermentation can provide various benefits such as unique flavor, health and nutrition, texture and safety (shelf life), while maintaining a 100% natural label. In this review several examples are presented on how fermentation is used to replace, modify or improve current, artificially produced, foods and beverages and how also fermentation can be used for completely novel consumer products.
Kvass is a fermented cereal beverage which produced from malt, rye flour, stale rye bread, and sucrose and is consumed mainly
in Eastern Europe. Moreover, it is of interest as one of the few examples of traditional, non-alcoholic cereal-based beverages.
In this study, a commercial kvass sample was characterized with respect to the fermentation microflora and the concentration
of microbial metabolites. Lactobacillus casei and Leuconostoc mesenteroides were present in cell counts of 7.3×107 and 6.0×107cfumL−1, respectively. Saccharomyces cerevisiae was present in cell counts of 3.0×107cfumL−1. PCR-DGGE analysis verified that all dominant fermentation organisms were cultivated. Microbial metabolites in kvass were
ethanol, lactate, and acetate. One of the kvass isolates, Ln. mesenteroides FUA 3086 harboured a putative dextransucrase gene and formed dextran and isomalto-oligosaccharides from sucrose and maltose.
Fermentation of model kvass wort confirmed that all kvass isolates grew in the fermentation substrate, moreover, formation
of isomaltotriose by Ln. mesenteroides FUA 3086 was observed in model kvass fermentation.
As we move further into the 21st Century, sensory and consumer studies continue to develop, playing an important role in food science and industry. These studies are crucial for understanding the relation between food properties on one side and human liking and buying behaviour on the other. This book by a group of established scientists gives a comprehensive, up-to-date overview of the most common statistical methods for handling data from both trained sensory panels and consumer studies of food. It presents the topic in two distinct sections: problem-orientated (Part I) and method orientated (Part II), making it to appropriate for people at different levels with respect to their statistical skills. This book succesfully: Makes a clear distinction between studies using a trained sensory panel and studies using consumers. Concentrates on experimental studies with focus on how sensory assessors or consumers perceive and assess various product properties. Focuses on relationships between methods and techniques and on considering all of them as special cases of more general statistical methodologies. It is assumed that the reader has a basic knowledge of statistics and the most important data collection methods within sensory and consumer science. This text is aimed at food scientists and food engineers working in research and industry, as well as food science students at master and PhD level. In addition, applied statisticians with special interest in food science will also find relevant information within the book.
Production of fermented kvass malt
- B Sacher
Sacher B. (2013) Production of fermented kvass malt.
Brauwelt International, Vol. 31, No. 4, p. 202 210.
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lpp.