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The characterisation of selected type of „bio“ dairy product
Hanychová, Silvie ; Trachtová, Štěpánka (referee) ; Vítová, Eva (advisor)
This bachelor thesis deals with the sensory evaluation of kefir. Specifically the differences in the sensory properties of kefir produced using the same method from various types of milk were observed. The theoretical part was focused on kefir, its characteristics, composition and production using kefir grains. The experimental part deals with the comparison of four kefir samples based on sensory evaluation. The evaluation was made by the students from Faculty of Chemistry BUT, the untrained assessors. Therefore the evaluation results may be closely reflecting the opinions of common consumers. The samples of kefir were subjected to sensory evaluation by the ranking test and the pleasantness of chosen properties (appearance, colour, texture, odour and taste) was evaluated using a seven-point scale, as well as the overal acceptability of samples. The results were statistically processed and graphically evaluated.
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Biopolymer particles based on polyhydroxybutyrate
Gregušková, Zuzana ; Zemanová, Jana (referee) ; Přikryl, Radek (advisor)
This Bachelor´s thesis deals with preparation of abrasive particles from poly(3-hydroxybutyrate) and their optimization for cosmetics usage. It explores morphology of prepared particles and its effect on their abrasive ability. Moreover, it compares abrasive effectiveness of prepared particles with those commercially available. Several types of preparation methods of biopolymer particles such as milling, fibre spinning, pelletisation and solution preparation were carried out and optimized. Prepared particles were analysed using scanning electron microscopy. Semi-automatic system for testing of abrasiveness of prepared particles was made up from basic parts of 3D printing machine. This device was tested and calibrated using floral foam and sandpaper with different grades of granularity and used for comparison of abrasiveness of prepared particles. Mechanical response of particles under pressure was also investigated. It was found out that measured mechanical properties correlate with the data from abrasiveness test. Size and shape of particles, their morphology, mechanical properties and abrasiveness can be controlled depending on the preparation method used. Selected prepared and commercial abrasive particles were applied into prepared cosmetic foundations for peeling with the goal of sensory evaluation of abrasive effectiveness of prepared particles.
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The addition of carbon dioxide to milk for cheese production
Králová, Petra ; Hrstka, Miroslav (referee) ; Kvasnička, Miloš (advisor)
This work deals with the addition of carbon dioxide to milk for cheese production. The first aim was to elaborate a literary search focused on chemical composition of milk and its changes after addition of carbon dioxide and to describe production processes, with or without addition of carbon dioxide. The opening part was in particular focused on production of cheese with carbon dioxide and what all this gas causes during production. Carbon dioxide significantly decreases pH, thereby preventing from multiplication of undesirable microorganisms, it is also very important for shortening of production time, because it shortens the coagulation time. The main aim of experimental part was to determine the optimum addition of carbon dioxide to milk for production of Balkan cheese and using several analytical methods to compare cheese produced with and without addition of carbon dioxide. The sensory methods suitable for following of sensory differences of produced cheeses were also chosen and applied. By request of Dairy in Polná Ltd., the operation economy was calculated, which revealed that production with carbon dioxide is very useful and can reduce production costs of Balkan cheese, which would certainly be positive. The advantages and disadvantages of cheese production with carbon dioxide for consumers as well as for producer are evaluated as conclusion of this work.
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Influence of selected active compounds for properties of gel and emulsion cosmetics
Gardoňová, Lenka ; Pekař, Miloslav (referee) ; Zemanová, Jana (advisor)
This master‘s thesis studies problems of chosen active substances in cosmetic emulsions and gels. There is their main characteristics – distribution and properties of cosmetic emulsions and gels, preparation of the active substances, effects on the skin and conditions, which could them influence. In experimental part, preparation of gels and emulsions bases was described which were than enriched by active substances - evening primrose oil, hemp oil, Salvia officinalis extract, Symphytum officinale extract and sea salt. Properties of these cosmetic gels and emulsions bases with the addition of active substances depend on temperature and method of storage, amount of light exposure, method of preparation and another conditions. Action of these factors can cause changes of the stability, thereby the cosmetics effects on the skin can be lost. On the bases of performed rheology measurements (oscillation and flow measurements), pH measurements and sensory analysis were determined, if the properties of examined samples were changed. The measurement was performed in the certain time intervals and the properties were evaluated like at laboratory temperature 23±2 °C, so after exposure to temperature regime 37 °C in thermoregulator. On the basis of performed measurements, there was determined, that gel base with addition of Symphytum officinale extract had the most stability properties.
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Technologie výroby čerstvých sýrů v závislosti na použitých surovinách a podmínkách výroby
Koudelková, Jana
In the theoretical part, this diploma thesis first deals with the definition of fresh cheeses and also describes the history of cheeses in general. Subsequently, cheeses are classified based on several factors and the basic representatives of fresh cheeses are described here. It describes what raw materials are necessary for the production of fresh cheese, and how the process of their creation looks step by step. The work contains information on the basic sensory properties of fresh cheeses and possible defects that may occur in fresh cheeses. The last part of the theoretical work is focused on potential factors in the production of fresh cheese that could affect the quality and taste of the final product, including the possibilities of its quality control. In the experimental part of the thesis, raw materials and procedures for the production of fresh cheese were first selected, and then the production of fresh cheese itself took place. After production, the basic chemical and sensory properties of the manufactured products were determined. The results showed that the produced fresh cheeses corresponded chemically to the general values and the spices used significantly influenced parameters such as the taste and aroma of the cheese. Provençal spices were used for flavoring; paprika and pepper; wild garlic and dill; Italian herbs, which in the end were evaluated as the best option for flavoring cheeses. The obtained results were processed into graphs and evaluated statistics.
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Technologie výroby a hodnocení jakostních parametrů bílých sýrů v solném nálevu
Mištová, Dominika
This thesis deals with the production technology and quality parameters evaluation of white brined cheeses. The characteristics, origins, technological procedures of production, and differences between them are described. The work aimed to carry out sensory evaluation and determination of physicochemical parameters. These criteria were identified for selected representatives of white brined cheeses available on the Czech market and for own samples produced under semi-operating conditions. A sub-objective was to compare both individual samples with each other and commercially available samples with the data given on the manufacturer's packaging. When comparing the results of the analysis with the data indicated on the package, the protein and fat content in both cases of commercially available samples was higher than declared by the manufacturer. On the other hand, the course of souring in the produced cheeses was insufficient. The titration results of the produced cheese samples differed by almost half from the cheeses purchased on the domestic market.
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Možnosti úpravy těst a jejich fortifikace při výrobě pekárenských výrobků
Samenova, Madina
The theoretical part focused on the history of bakery, traditional technological procedures, the legislative concept of bread types, requirements for their quality parameters and additives to improve the properties of pastry. Special attention was also paid to fortifications and non-traditional methods of fortifications in Kazakhstan. The practical part involved a baking experiment, where 5 different variants of bakery products were baked and evaluated. The fortified variants contained the additions of vegetable or fruit powder (10 % by weight of flour). The baked products were then subjected to sensory analysis, which was evaluated statistically and by the method of sensory profile. The variant with the addition of banana powder can be denoted as the best product in terms of sensory acceptability. The high evaluation of this variant can be ascribed to its approaching to the control variant (without fortifiers).
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Výroba masných výrobků a jejich zhodnocení
Válka, Jiří
The theoretical part of the thesis describes the requirements for meat processing and for the production of meat products and their marketing. The technological sche-me of production, the necessary background for the production of sausages and the requirements for production today and in the past are also described here. In the practical part of the thesis, we examined the production process of Poličany salami, Hunter's salami, and Hunter's and Pirate's sausages. In this investigation, we were investigating production losses. These losses are very balanced and for Poličany salami they are 35.54%, for Hunter salami 36.11%, for Hunter sausages 43.82% and for Pirate sausages 43.54% of weight. Furthermore, it was investigated how these los-ses affect the price. We have found that when stored longer than necessary, the weight is constantly reduced and thus the manufacturer loses any profit. The last parameter assessed was sensory quality. In this case, we found that sausages are preferred less dried among men, on the contrary, more dried among women. In the case of salamis, it turned out that Hunter's salami is better less dried, on the contrary, Poličan salami is more.
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Čokoládové cukrovinky s přidanou hodnotou
Týblová, Kateřina
Chocolate has a high popularity among consumers. With increasing interest in the effect of diet on human health, the effort to produce new and healthier foods also increases. Therefore, the aim of this thesis was to design enriched chocolate products. In total, six types of chocolate bars (white, matcha, freeze-dried mango, crushed cocoa beans, ginger, cinnamon) and five types of chocolate pralines (cream, tea with matcha, chia seeds, mango with freeze-dried mango, mango with chilli) were produced. The products then underwent sensory evaluation and measurements of firmness, total polyphenol content and water activity. In the case of chocolate bars, the ingredients affected mainly the taste and overall impression, but it also affected the firmness. The nutritionally valuable ingredients also increased the level of polyphenols with statistically significant difference. Water activity was affected in only one variant. Water activity of pralines was not affected. The total polyphenol content in chocolate pralines was increased in only one variant. The added ingredients affected the firmness of filling, its taste and texture, although there was no statistically significant difference in overall impression.
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Pralinky a variabilita jejich výroby
Pešák, Michal
In a first part of the bachelor's thesis is a research of literature concerning history of chocolate itself, legislative requirements, differentiating of a cocoa tree on particular breeds and processing of cocoa beans. In addition to that are mentioned technological steps of creating chocolate matter, its most common defects. The conclusion is dedicated to dessert candies – pralines. Within a practical part were created pralines with three different surface adjustments and three different fillings. As fillings were used peppermint, a passion fruit and salty caramel. Surface adjustments were done by food colours. Created pralines were silver-plated and marbled and compared with pralines with no surface adjustments. A sensory analysis was undertook and from results of sensory questionaries was created a sensory profile for each kind including statistical evaluation. Products were evaluated positively by evaluators, all were characterized by very good quality and execution, therefore no statistically great differences were noticed.
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