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Factors affecting stability and consumer acceptance of sauerkraut water
Vašků, Barbora ; Mikulíková, Renata (referee) ; Márová, Ivana (advisor)
This diploma thesis is focused on the optimization of pasteurization of the cabbage juice in order to extend its shelf life. The theoretical part is focused on the description of the sauerkraut production technology and characterization of the main components of fermented cabbage and its juice, it also deals with pasteurization options and presence of probiotic strains. In the experimental part, the composition of the brine was analyzed from a chemical point of view (bioactive substances, sugars, carbohydrates), from a microbiological point of view (presence of probiotics, pathogenic organisms) and the effect of selected pasteurization processes on these components. Pasteurization at 90 °C for 0.5 minutes was determined as the most suitable treatment, during which potential pathogens are being eliminated, while most of the original bioactive components are preserved. After suggesting the effective pasteurization treatment, suitable species of genus Lactobacillus was selected to enrich the cabbage juice product because of decreasing of probiotics viability during pasteurization treatment. The strain Lactobacillus plantarum was determined as the most suitable probiotic species for cabbage juice enrichment, due its ability to survive in 2 weeks storage at 8 °C in cabbage juice. Chemical composition after 2 weeks of incubation with mentioned organism has changed. Quantity of lactic and acetic acid increased, while no changes in content of vitamin C were observed. Finally, sensory analysis was performed to evaluate suggested mixed fruit-vegetable drink. According to results of sensory analysis, the drink composed of cabbage juice and apple-beetroot juice in the ratio of 2:1 was found as the most acceptable.
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Vliv fermentace a teplené úpravy na stravitelnost hrachového proteinu v podmínkách in vitro
Dunová, Jana
This diploma thesis entitled "The effect of fermentation and heat treatment on the digestibility of pea protein in vitro" deals with the preparation of a comprehensive overview of the pea (Pisum sativum), its properties, anti-nutritional substances and possibilities of practical use. As follows, there is a description of the structure and function of proteins, as well as methods of their detection. Other chapters deals with digestion in general, description of fermentation and heat treatments. The aim of this thesis was to offer a comprehensive view of the digestibility of proteins and carbohydrates, as well as the effects of anti-nutritional compounds (raffinose, polyphenols and phytic acid). Samples boiled or fermented with Lactobacillus plantarum were used. The study showed that short (10 minutes) cooking did not significantly affect protein digestibility, but longer (120 minutes) cooking reduced digestibility by 10 % due to the Maillard reaction. For amino acids, a higher content of cysteine, methionine and glutamine was observed compared to non-fermented samples. Carbohydrates subjected to long cooking proved to be the most digestible, and fermentation improved the nutritional value of pea flour. Treatments had different effects on antinutritional compounds, with raffinose being reduced by fermentation and increased by heat treatment, while the opposite was true for polyphenols. Phytic acid was significantly reduced by digestion regardless of treatment.
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Processing of sauerkraut juice to enhance its stability and consumer acceptance
Kohoutová, Lenka ; Mikulíková, Renata (referee) ; Hoová, Julie (advisor)
This diploma thesis focuses on the development possibilities of fruit and vegetable juices containing sauerkraut juice, the characterization of their nutritional and sensory qualities and their stability, as well as the potential for enriching selected juices with probiotic culture of Lactobacillus plantarum. The best combinations of various juice mixtures were selected based on sensory analysis and were stored for 30 days at 8 °C. Changes in selected parameters were monitored during the storage. Antioxidant activity, total flavonoids and polyphenols content and content of total water-soluble and reducing saccharides were determined by spectrophotometric methods. HPLC was used for lactic and L-ascorbic acid determination, flow cytometry was used for probiotic cell content determination, culture test was used to observe viability of cells, pH was monitored. Contents of antioxidant activity and of total polyphenols content did not drastically change during the storage. Major changes were observed in total and reducing sugar content and total flavonoids content. It was observed that probiotic viability was preserved for 14 days, decrease occurred afterwards. In order to achieve as high content of probiotics as possible, it would be advisable to store probiotically enriched juices for maximum of 14–19 days at temperature of 8 °C. The highest viability was observed in JHM sample (containing apple, pear, carrot and sauerkraut juice in the same ratio). Even through viability of probiotic cells was determined as low, these presented functional beverages remain nutritionally, visually and taste-wise interesting products, which can help popularize the consumption of non-traditional local foods.
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Factors affecting stability and consumer acceptance of sauerkraut water
Vašků, Barbora ; Mikulíková, Renata (referee) ; Márová, Ivana (advisor)
This diploma thesis is focused on the optimization of pasteurization of the cabbage juice in order to extend its shelf life. The theoretical part is focused on the description of the sauerkraut production technology and characterization of the main components of fermented cabbage and its juice, it also deals with pasteurization options and presence of probiotic strains. In the experimental part, the composition of the brine was analyzed from a chemical point of view (bioactive substances, sugars, carbohydrates), from a microbiological point of view (presence of probiotics, pathogenic organisms) and the effect of selected pasteurization processes on these components. Pasteurization at 90 °C for 0.5 minutes was determined as the most suitable treatment, during which potential pathogens are being eliminated, while most of the original bioactive components are preserved. After suggesting the effective pasteurization treatment, suitable species of genus Lactobacillus was selected to enrich the cabbage juice product because of decreasing of probiotics viability during pasteurization treatment. The strain Lactobacillus plantarum was determined as the most suitable probiotic species for cabbage juice enrichment, due its ability to survive in 2 weeks storage at 8 °C in cabbage juice. Chemical composition after 2 weeks of incubation with mentioned organism has changed. Quantity of lactic and acetic acid increased, while no changes in content of vitamin C were observed. Finally, sensory analysis was performed to evaluate suggested mixed fruit-vegetable drink. According to results of sensory analysis, the drink composed of cabbage juice and apple-beetroot juice in the ratio of 2:1 was found as the most acceptable.
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Vliv rekombinantní bakterie Lactobacillus plantarum na vývoj pylové alergieL
Schwarzer, Martin ; Repa, A. ; Wiedermann, U. ; Hrnčíř, Tomáš ; Daniel, C. ; Pot, B. ; Štěpánková, Renata ; Hudcovic, Tomáš ; Tlaskalová, Helena ; Součková, Martina ; Kozáková, Hana
Germfree mice were monocolonized with recombinant Lactobacillus plantarum producing Bet v 1. Subsequently mice were sensitized by intraperitoneal injections to Bet v 1. We found out that monocolonization with recombinant L. plantarum reduced the level of specific Bet v 1 specific IgE antibody and stimulated production of INF-gamma in spleen cells supernatants. We conclude that monocolonization by recombinant L. plantarum shifts the immune response towards Th-1 direction and that it is a promising vaccine candidate against type I allergy
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