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Sledování změn jakostních ukazatelů při prodloužení doby trvanlivosti tepelně opracovaných masných výrobků
Holčíková, Radmila
This thesis „Monitoring of changes in quality indicators when prolonging the shelf life of heat-treated meat products“, deals with the legislativ, composition and procesing of heat-treated meat products in the first part. Next part describes the possibilities inactivation of microorganisms and sensory analysis. The last part of the literature review deals with a food packaging. The practical part deals with sensory evaluation of two samples with different meat kontent during the period of seven months. The appearence, the surface of the intestine, texture (by touch), surface of the cut, smell, smell intensity, texture (biting), taste, taste intensity, salinity, the presence of acidic, metallic, sweet and bitter taste were evaluated. Results were processed using Duncan's test and evaluated. It was found that the sensory evaluation of both samples did not differ much from each other. For both samples, it would be possible to extend the date of minimum durability to seven months.
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Hodnocení výrobku z chmelových výhonků
Heinereichová, Iva
The diploma thesis deals with sensory assessment, measurement of color and pH of six batches of hop shoots, which differ harvest days and pasteurization, dipping in water overnight and repeated pasteurization. Young shoots of hops were harvested during April. It is a pasteurized product from sweet-sour pickled hop shoots. Results of sensory assessment of hop shoots showed between batches a statistically significant difference (P <0,05) in a number of descriptors. Results of sweet-sour pickle did not showed differences between batches. The difference between batches was only for the purity descriptor. The term of harvest shoots may affect the sensory quality of hop shoots. Dipping of shoots overnight in water and the long-term effect of the pasteurisation temperature worsened the texture and color of the shoots.
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Vliv způsobu odkalení moštů na výslednou jakost vín révy vinné
Suská, Alžběta
The diploma thesis dealt with the influence of deselination on the quality of wine. In the theoretical part were used various methods of deselination and bentonite use were described. Furthermore, terms such as clarification or the intensity of deselination were explained. In the experimental part, an experiment was performed on two grapevine varieties. Seven different deselination methods have been developed for each variety. It has been monitored the influence of deselination methods on the proces of fermentation, on the weight of sludge after fermentation. Furthermore, the individual wines were evaluated sensorycally, analytically and the results statistically evaluated. Sensorycal evaluation was carried out on a hundred-point scale, and aromatic wine profiles were created. Chemical analysis was performed on FTIR Alpha and Miura One. The most suitable statistical method was chosen for the results.
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Štúdium antioxidačných vlastností čajov
Džuppa, Mikuláš
The Diploma Thesis is focused on the analysis of the antioxidant qualities and attributes of different kinds of tea under their specific methods of preparation. Literature overview provides history, processing technology, distribution and the most common means of tea preparation as well as its content substances. The Thesis discusses the overall containment of polyphenols and antioxidant capacity based on the FRAP and DPPH methods but also the amount of vitamin C in the tea samples. The Thesis elaborates on the undertaken sensor analysis of chosen samples and examines the tea content substances during its traditional preparation as well as during its preparation in a non-typical way.
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Bylinné nápoje na bázi piva
Doležalová, Vanda
In the teoretical part of this thesis is breefly written about history of brewing beer, beer ingredients, brewing proceses and methods by which the beer is analyzed (instrumental and sensoric methods) and also contains legislative requirements for herbal beers and for beverages that are based on beer. In the practical part are mentioned processes of making beer using herbs and other materials. The final product is beer containing extracts of lemon balm (Melissa officinalis L.) and common yarrow (Achillea millefolium agg.). Antioxidant capacity was defined by DPPH and FRAP methods. To monitor sensory acceptance for herbal beers sensory analysis was used.
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Analytické a senzorické hodnocení odrůdových šťáv z jablek
Sochorcová, Nicola
This diploma thesis deals with the sensorial and analytical evaluation of varietal juices from apples. All the juices were made from apples from the orchad of Faculty of Horticulture in Lednice. Together was assessed a total of nine varieties. The theoretical part of the thesis deals with the origin, distribution and utilization of apples in the processing industry, the technology of production of apple juice, its individual basic substance components, conditions and methods of sensory analysis of food. For all samples was carried out analytical and sensory evaluation. The juices produced were sensorially evaluated by the following parameters: appearance and colour, consistency, taste and aroma, intensity of taste after swallowing and overall rating. In the context of analytical reviews were established: titratable acids, soluble solids, content of total polyphenols, ascorbic acid and Malic acid content. The results obtained from the analytical and sensory evaluation were graphically and statistically evaluated.
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Použití nasycených vyšších mastných kyselin v technologii vína
Chvalinová, Klára
Sulfur dioxide has been used in the wine industry for many centuries due to its antimicrobial and antioxidant effects. However, the problem is that SO2 is a major allergen and when consuming higher doses, health complications (such as headaches, stomach aches, asthmatic problems) may occur. It is therefore important to find a suitable substitute, or rather a supplement to this substance. One of the options is the use of saturated higher fatty acids (HFA). These substances naturally occur in nature and a small amount of them is formed by yeasts themselves during fermentation. Thanks to HFA the yeast cells´ lipid membranes are changed (their liquidity), resulting in cell degradation, slowing of metabolism and thus slowing down the fermentation until it is stopped. In this experiment, a mixture of HFA, octanoic, decanoic and dodecanoic acid, ratio 2:7:1, respectively, was used at doses of 5, 10, 20, 30, 40 and 60 mg/l, with two variants of the application SO2, 20 mg/l or 40 mg/l. The HFA residues, the corresponding ethyl esters and the influence on sensory properties of the wine were observed. The results of this experiment show (or HFA residues) that the more HFA is added, the more they are absorbed by the yeasts. At the same time there was a very slow esterification in time and thus a low influence on the aroma of wine. Sensory analysis showed the HFA dose of 20 mg/l as the limit from which we are able to recognize differences in HFA doses. There was also an influence of sludge particles. The longer the wine matures, the less sludge particles it contains, hence the HFA are bound on the yeast cells, and thereby their influence on wine sensory is reduced.
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Kvalitativní parametry vybraných sirupů v maloobchodní síti
Červinková, Veronika
This thesis was prepared at the Institute of Post-Harvest Technologies of Horticulture at the Faculty of Horticulture of the Mendel University in Brno in years 2016/2017. The aim of the thesis is to determine qualitative parameters of syrups in retail shops. The thesis contains technological processing and quality requirements for syrups. The practical part deals with the evaluation of selected parameters. The syrup of the YO brand, which showed the highest antioxidant capacity and all polyphenols, was evaluated as the best. The worst parameters were Neli's syrup, which did not contain any fruit component.
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Qualitative parameters of selected foods in the gluten-free diet
Jiříková, Eva ; Doležal, Marek (advisor) ; Pánek, Jan (referee)
The gluten contained in some cereals plays an important role in the quality of bakery products. However, it is also associated with a range of diseases which require a gluten-free diet. In the first part of the work there is a brief overview of the knowledge on the given topics. The aim of this work was to compare qualitative parameters of selected foods (long-life bakery products) for gluten-free diet. The work included 31 different long-life bakery products (biscuits, wafers, sponge biscuits, extruded products, cracker products) from various producers (including 8 gluten products). The information on the product labels indicates that the food is energy-rich (1640-2310 kJ). Carbohydrates accounted for the largest share of 2/3 of products (48.3-77.8%), of which sugars accounted for more than 10% of the energy value. The remaining 1/3 of the products were rich in fats (49.2-66.8%). The energy content of protein was low (<13%) in all products. After extraction of fat and conversion of fatty acids to methyl esters, the fatty acid composition was determined by gas chromatography (GC-FID). Predominantly represented were monounsaturated fatty acids (MUFA) with 16.1-83.6%, and polyunsaturated fatty acids (PUFA), with 0,6-25,4%. Three samples exceeded, in 100 g of product, the saturated fatty acid intake (SFA)...
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Effect of roasting on the sensory profile of coffee
Šajdlerová, Kristýna ; Vítová, Eva (referee) ; Diviš, Pavel (advisor)
This bachelor thesis deals with the effect of roasting on the content of carbohydrates and aromatic compounds in coffee. It also studies changes in coffee acidity based on different level of roasting. In the practical part there was measured pH, it was conducted setting of glucose, fructose and sucrose content by liquid chromatography, analysis of aromatic compounds using gas chromatography and also sensoric analysis of 17 types of coffee. Each one was roasted using two different temperatures (210 °C and 240 °C). Based on the statistical processing of basic chemical analysis and sensory analysis, significant differences were found between determined parametres of coffee samples roasted at 210 ° C and 240 ° C. Processing of results of sensory and chemical analysis of coffee samples did not manage to differentiate coffee samples from each other based on their geographic origin. At a lower level of coffee roasting there was found weak, but statistically significant correlation between the results of the sensory analysis and the content of aromatic compounds, while for the higher degree of coffee roasting no correlation was found.
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