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Encapsulation of selected natural extract for food application.
Vyskočilová, Terezie ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
This diploma thesis deals with encapsulation of natural extracts. In the theoretical part the methods of encapsulation, materials for particle preparation, as well as application of encapsulation techniques in food industry were described. In experimental part selected natural extracts of propolis, green barley and probiotics were characterized. There substances were encapsulated into alginate and chitosan. In the total of 25 types of prepared particles long-term stability in some model physiological conditions as well as in four different model foods was evaluated. Additionally, stability of selected particles in several real milk-based products was followed too. The stability of particles was determined spectroptohometrically. In natural extract a content of polyphenols, proteins, chlorophylls, as well as total antioxidant activity were analysed. To analysis of probiotics optical and fluorescence microscopy were used. In propolis and green barley antimicrobial activity was tested too. Moreover, in the sample of propolis also cytotoxic assay was applied. Agar-chitosan was chosen as the best shell material for propolis due to its optimal stability in model physiological conditions as well as model foods. Liposomes were evaluated as unstable and were not recommended for further application. As the suitable shell material for powdered green barley starch-alginate (rate 1:4) and agar-chitosan were proposed, while the second one showed better stability for released proteins. Agar-chitosan shell material was usable for fresh green barley too. For probiotics encapsulation alginate or alginate-starch were chosen because of their porosity and possibility of nutrients diffusion. In real foods the best results were reached with application of probiotic particles into milk. Coencapsulation of powdered barley and probiotics did not confirm inhibition of culture growth. Neither the antimicrobial effect of propolis and barley nor the cytotoxic effect of propolis were confirmed.
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Ovlivnění stability šťávy zeleného ječmene pomocí obsahových látek z vybraných rostlinných druhů
Juříčková, Jana
The thesis „Affecting the stability of the juice of green barley using the content substances of selected plant species“ is usage of green barley substances, the green barley juice production and its stabilization with various plant extracts. In the theoretical part the aim is to define young green barley, important substances in the plant and how to obtain them, which plant extracts and preservation methods are used in barley juice production. The practical part of this thesis is about cultivating green barley in laboratory conditions, its processing with plant extracts addition and the effeciency monitoring for 3 weeks. Plant extracts have antimicrobial activity against various microorganism, and so the extracts are suitable for juice preservation. Moreover the extracts help to preserve the nutrients in the juice.A microbiological risk assessment was performed on a samples with the plant extracts and a microbiological evaluation was done in a stastistical analysis software. The result from the microbiological evaluation the most effective against microorganisms was Silybum m. extract.
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Technologie pěstování a hnojení ječmene (Hordeum) s cílem maximální kvality produktu a jeho využití pro výrobu doplňku stravy "zeleného ječmene".
OPOLZER, Pavel
In this thesis, I focused on the cultivation and fertilization of barley and its use as a food supplement called "green barley". Nowadays people eat unhealthily, they do not diet, their food intake consists of a few essential nutrients and this leads to various illnesses and diseases. Green Barley is one of the ways how to replenish essential nutrients, such as vitamins, minerals, enzymes and others. Its regular use can achieve better physical condition and health and it also prevents from various diseases such as anemia, cancer, heart disease, blood vessels and skin diseases etc. The aim of this study was to figure out the best way of cultivation and fertilization of green barley. One of the best methods is practiced in the US, where green barley is grown on dried-up freshwater lakes where there is a very fertile soil and green barley can grow in ecological way. In the Czech Republic, it is better to cultivate green barley in conventional agriculture environment because the soil is fertile and there is a little need to fertilize it. If green barley in our area grew in ecological way, it would increase the nitrate content in the plant due to nitrogen-potassium fertilizer manure. The plant is not able to convert all the nitrogen in organic substances and redundant nitrogen remains in the plant in the form of nitrates.
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Encapsulation of selected natural extract for food application.
Vyskočilová, Terezie ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
This diploma thesis deals with encapsulation of natural extracts. In the theoretical part the methods of encapsulation, materials for particle preparation, as well as application of encapsulation techniques in food industry were described. In experimental part selected natural extracts of propolis, green barley and probiotics were characterized. There substances were encapsulated into alginate and chitosan. In the total of 25 types of prepared particles long-term stability in some model physiological conditions as well as in four different model foods was evaluated. Additionally, stability of selected particles in several real milk-based products was followed too. The stability of particles was determined spectroptohometrically. In natural extract a content of polyphenols, proteins, chlorophylls, as well as total antioxidant activity were analysed. To analysis of probiotics optical and fluorescence microscopy were used. In propolis and green barley antimicrobial activity was tested too. Moreover, in the sample of propolis also cytotoxic assay was applied. Agar-chitosan was chosen as the best shell material for propolis due to its optimal stability in model physiological conditions as well as model foods. Liposomes were evaluated as unstable and were not recommended for further application. As the suitable shell material for powdered green barley starch-alginate (rate 1:4) and agar-chitosan were proposed, while the second one showed better stability for released proteins. Agar-chitosan shell material was usable for fresh green barley too. For probiotics encapsulation alginate or alginate-starch were chosen because of their porosity and possibility of nutrients diffusion. In real foods the best results were reached with application of probiotic particles into milk. Coencapsulation of powdered barley and probiotics did not confirm inhibition of culture growth. Neither the antimicrobial effect of propolis and barley nor the cytotoxic effect of propolis were confirmed.
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Determination of beta-carotene in barleycorn by HPLC
Puč, Vojtěch ; Maleček, Miroslav (referee) ; Prýma, Jaroslav (advisor)
This diploma thesis deals with the natural antioxidants present in cereals, especially in barley (Hordeum vulgare). A close attention is paid to the study of carotenoids determination was conducted. In the experimental part, the method of beta-carotene determination was optimized using high-performance liquid chromatography, diode array detector and mass detector (HPLC/DAD/APCI-MS). The method was used for the beta-carotene and lutein determination in the samples of barleycorn, malt and green barley. This method involves the sample saponification, extraction by diethylether, followed by separation on ODS Hypersil 250x4,6 mm, 5m column, using MTBE/MeOH (20:80) as mobile phase and spectrophotometric detection (450 nm). Quantitative analysis was implemented in the HPLC/DAD system. The MS detector was used for identification of analytes. A number of still unpublished data about the content of beta-carotene and lutein in several varieties of malting barley, malt and green barley are stated in this thesis. The highest content of beta-carotene was found in the green barley sample of variety Malz, harvested in first grow phase (8,49 mg/kg of the dry matter). The content of beta-carotene in barleycorn is relatively low (0,07-0,14 mg/kg of the dry matter). The content of beta-carotene is several times higher in the malt produced from barleycorn (0,24-0,56 mg/kg of the dry matter). The diploma thesis was implemented in the Research Institute of Brewing and Malting, Plc. in Brno.
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The technology of cultivation and fertilization of barley (Hordeum) for the manufacture of food supplements' green barley ".
DARDOVÁ, Magdaléna
The aim of this thesis was to study the technology of cultivation and fertilization of barley (Hordeum) for the manufacture of food supplements' green barley ". The main active ingredients in green barley enzymes are superoxide dismutase, catalase, peroxidase, cytochrome oxidase and transhydrogenase. Other ingredients are flavonoids saponarin, glykosylisovitexin and lutonarin. In producing research was determined the best technology for cultivation and fertilization of green barley. Most substances contains barley grown in organic farming. On the contrary, this barley has a higher content of nitrates due to the exclusive use of manure, which are nitrogen-potassium, and in such a system is a factor in low phosphorus. According to the Liebig law nitrogen which is not in balance with the element in the minimum, it is not able to transform plant nitrogen organic substances. From a nutritional point of view seems to be the best ecological cultivation of barley on dry freshwater lakes in the USA. The soil in these areas contain enough nutrients for barley, which is a prerequisite for good quality products. If green barley grown in the Czech Republic, it would be most appropriate cultivation conventional manner. The soils are poor in nutrients, and thus would only manure was insufficient. The increase of the active substances it is appropriate to use any of several kinds of elicitors. The most suitable varieties would malting barley varieties Sebastian, which includes most of the active substances.
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