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Influence of Storage Conditions on Metabolic Profile of Apples
Duroňová, Kateřina ; Vávrová, Milada (referee) ; Kráčmar, Stanislav (referee) ; Márová, Ivana (advisor)
The goal of presented dissertation has been complex analysis of changes in content of fatty acids, enzymatic and low-molecular antioxidants in apples and related evaluation of perception of originators of storage diseases for apples stored in various conditions. Main part of the work has been dedicated to study of the impact of storage of apples in modified atmosphere with reduced amount of oxygen and in reference “normal” atmosphere for six months. Next part of the work has been dedicated to study how apple storage in common, consumer affordable, conditions (storage in a cellar, in a refrigerator, and in room temperature) affects content of low-molecular antioxidants. For testing has been selected apple kinds Jonagored, Golden Delicious, Idared, Šampion, and Granny Smith. Within the scope of this work has been optimized the method for determination of fatty acids in plant material with higher content of wax. The measured values imply the apples are valuable source of many important nutrition substances like vitamins, provitamins and antioxidants. During the storage process these substances exhibit considerable protective function. Long-term storage, mainly in the atmosphere with reduced amount of oxygen (FAN), enables preservation of majority of these important nutrition substances depending on the kind of apple and conditions of storage. Freezing process is conservative to apples (mainly in the presence of protective substances), while in the process of drying the values of all monitored antioxidants decrease depending on temperature and conditions of drying. Upon the choice of the storage method one must consider nutrition, sensoric characteristic and consumer demands.
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Determination of athenticity of plant foods by molecular techniques
Plášková, Anna ; Mikulíková, Renata (referee) ; Němcová, Andrea (advisor)
The aim of presented diploma thesis was to determination of authenticity of fruit baby foods for early infant feeding using molecular methods. In the experimental part, isolation kit was used for isolation of plant DNA from fruits (strawberry, apricot, raspberry, apple) and from six commercial fruit products for children. Isolated DNA was characterized and verified using PCR methods with primers specific for plant rDNA (ITS2). Specific primer pairs were designed to amplify DNA for the detection of one fruit species. Primer specificity was assessed with four fruit species. A mixture of fruit puree from the two fruits was used to determine the sensitivity of the multiplex PCR assay. Six commercial fruit products were evaluated to verify the applicability of the multiplex PCR assay. The methodology of molecular detection of fruit DNA by qPCR and multiplex qPCR (duplex) includes approaches, which enable to detect two fruits (strawberry-raspberry, apricot-apple) in one reaction and thus reduces time and money requirements.
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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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Detection of undeclared fruit species in foodstuffs using methods of molecular biology and instrumental methods
Svobodová, Petra ; Wikarská, Monika (referee) ; Fialová, Lenka (advisor)
This thesis is focused on the detection of apple component in fruit-based baby food. The theoretical part deals with the fruit itself – the apple; food adulteration as a reason for the control of food composition and methods, both instrumental and those of molecular biology, by which food adulteration can be detected. In the experimental part, commercial products containing apple puree were purchased and model mixtures were prepared as replicas of the purchased products. DNA was isolated from these samples, its amplifiability was verified, and the presence of the apple component was detected after the selection of suitable species-specific primers. Methanol extracts for HPLC were prepared from the above-mentioned samples using a procedure previously used for the extraction of phenolic substances from apple pulp [1]. Using this analysis, apple in fruit purees was to be identified using phloridzin as a marker for the presence of the apple component. The result was a successful detection of the apple component in both commercial products and model mixtures using qPCR. However, the tested method of phenolic substance extraction proved to be unsuitable for use in the analysis of fruit purees, as phloridzin was not detected either in the apple puree extract or in the model mixtures to which this puree was added.
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Jaroslavice – place in the landscape
Galková, Ivana ; Eichler, Zdeněk (referee) ; Ponešová, Barbora (advisor)
The main aim of my thesis is to create sustainable local food production in Jaroslavice region. This region is situated near the Austria – Czechia border. The political changes of previous century influenced this rural location a lot. Changes resulted in socioeconomic degradation of this area. My project tends to shorten production connections between producers and consumers. It also takes the part with local farmers and farmer´s market. My architecture proposal is a building of regional food center focused on fruit production. The main fruits are apples, apricots and pitches according to the local climate conditions. The center has three main parts – processing, storage and retail.
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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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Apple Trees as Representatives the Utility Plants of the Tribe Rosaceae
Šnorová, Markéta ; Skýbová, Jana (advisor) ; Odcházelová, Tereza (referee)
TITLE Apple trees as representatives of utility plants in the menials Rosaceae AUTHOR Markéta Šnorová DEPARTMENT Department of biology and environmental education SUPERVISOR RNDr. Jana Skýbová ABSTRACT Submitted bachelor thesis is devoted to apple trees, as represantatives of menials Rosaceae. At first I introduced some other plants of family Rosaceae. My object was process theme apple tree from wider angle of view. From pollination until salvage and use their fetuses - apples. I have dealt also ecological requirements of appletree, their cultivation, varieties and history of their cultivation. Further I have highlighted importance of apples for humans in terms of nutrition. For the purpose of teaching i have compiled practical works useful in the lessons of botany at elementary school. And grammar school I suggested and laboratories tasks of chemistry and biology. KEY WORDS Apple tree, apple, cultivation, variety, nutrition.
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Detection of undeclared fruit species in foodstuffs using methods of molecular biology and instrumental methods
Svobodová, Petra ; Wikarská, Monika (referee) ; Fialová, Lenka (advisor)
This thesis is focused on the detection of apple component in fruit-based baby food. The theoretical part deals with the fruit itself – the apple; food adulteration as a reason for the control of food composition and methods, both instrumental and those of molecular biology, by which food adulteration can be detected. In the experimental part, commercial products containing apple puree were purchased and model mixtures were prepared as replicas of the purchased products. DNA was isolated from these samples, its amplifiability was verified, and the presence of the apple component was detected after the selection of suitable species-specific primers. Methanol extracts for HPLC were prepared from the above-mentioned samples using a procedure previously used for the extraction of phenolic substances from apple pulp [1]. Using this analysis, apple in fruit purees was to be identified using phloridzin as a marker for the presence of the apple component. The result was a successful detection of the apple component in both commercial products and model mixtures using qPCR. However, the tested method of phenolic substance extraction proved to be unsuitable for use in the analysis of fruit purees, as phloridzin was not detected either in the apple puree extract or in the model mixtures to which this puree was added.
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Determination of athenticity of plant foods by molecular techniques
Plášková, Anna ; Mikulíková, Renata (referee) ; Němcová, Andrea (advisor)
The aim of presented diploma thesis was to determination of authenticity of fruit baby foods for early infant feeding using molecular methods. In the experimental part, isolation kit was used for isolation of plant DNA from fruits (strawberry, apricot, raspberry, apple) and from six commercial fruit products for children. Isolated DNA was characterized and verified using PCR methods with primers specific for plant rDNA (ITS2). Specific primer pairs were designed to amplify DNA for the detection of one fruit species. Primer specificity was assessed with four fruit species. A mixture of fruit puree from the two fruits was used to determine the sensitivity of the multiplex PCR assay. Six commercial fruit products were evaluated to verify the applicability of the multiplex PCR assay. The methodology of molecular detection of fruit DNA by qPCR and multiplex qPCR (duplex) includes approaches, which enable to detect two fruits (strawberry-raspberry, apricot-apple) in one reaction and thus reduces time and money requirements.
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