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Study of physio-chemical properties of high-protein baking mixtures
Damborská, Alexandra ; Diviš, Pavel (referee) ; Pořízka, Jaromír (advisor)
In terms of nutrition, proteins are an integral part of the diet. They have many functions in the human body, and their lack in the diet has a negative effect on human health. For now, the biggest source of protein is animal production. However, plant sources, which are also rich in protein content, are also starting to come to the fore. Pastries are among the most consumed foods in the world. By adding protein isolates, concentrates or hydrolyzates, you can increase the protein content of baked goods and, in addition, enrich its amino acid profile. The following proteins were selected for the preparation of high-protein bakery mixes - pea protein isolate, wheat bran protein concentrate, beef protein hydrolyzate, brown rice protein isolate, egg white protein isolate, whey protein isolate, soy protein isolate, gluten and hemp protein concentrate. The protein content of plain wheat flour was determined to be 11%. The mixtures were mixed so that the resulting protein content was 20%. The reference sample of plain wheat flour T530 and the high-protein mixture were analyzed to determine the chemical and mainly the rheological properties. From the rheological determinations, a farinographic and extensographic analysis of the formed doughs was performed. The determined parameters were processed by the principal component analysis method to compare the properties against the reference.
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Fortification of bakery products with protein isolate from wheat bran
Bidmonová, Karolína ; Vítová, Eva (referee) ; Pořízka, Jaromír (advisor)
Proteins, as the major structural component of all cells and tissues, along with fats and carbohydrates, are a key macronutrient in human nutrition. An insufficient protein intake in the diet can lead to health problems and increasing protein malnutrition. Food fortification plays an important role in eliminating this protein deficiency. Wheat products, as a widely consumed food, seem to be a suitable commodity for protein fortification. Wheat bran was selected as a suitable source of protein due to its availability, protein content and relative simply method of a protein isolation. In the experimental part, the protein was extracted from wheat bran and used to prepare the mixtures. The mixture contained T530 flour and the 5%, 10% and 15% addition of the wheat bran protein isolate. From these mixtures, doughs were prepared and were subjected to chemical and rheological analysis. Finally, wheat baguettes with the addition of wheat bran protein isolate were made. The texture and taste properties of the baked products were verified by sensory analysis. The mixtures of flour and whey protein and a sample of unriched flour were also analysed to compare the results. Applied tests have shown that the addition of protein influences not only nutritional and chemical but also rheological properties. The addition of wheat bran protein isolate had a negative impact on the taste properties of the baguette Higher addition of BPI caused the increase of the bitterness of products. Taste optimization could be a topic for future study.
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Cereals - Active Substances, Biological Effects and Selected Applications in Food Industry
Lichnová, Andrea ; Tremlová, Bohuslava (referee) ; Vávrová, Milada (referee) ; Márová, Ivana (advisor)
The presented doctoral thesis is focused on the study of the biological effects of active compounds found in cereals, on the development of methods of analysis these effects, on the determination of the content of active substances and characterization of the relationship between composition and biological effects of cereals and cereal products. For the analysis several kinds of raw cereal samples (flakes, flour, germ, bran), flavored extruded cereal products and also samples of paddy and husked rice were chosen. To major types of analysed active compounds belong mainly phenolic compounds in the form of glycosides and aglycones, and also saccharides. Group parameters such as total polyphenols, flavonoids and total and reducing saccharides were determined spectrophotometrically, individual phenolics and saccharides were determined by high performance liquid chromatography (HPLC). TEAC, DPPH and CLAMS methods were used to determine the antioxidant activity. Indirect methods of determination of substances with antioxidant effect were used as well. Results of the total antioxidant activity were compared with values of antimutagenic/genotoxic activity obtained by several microbial test systems. Antimutagenic effect was expressed as a percentage of inhibition of effect of standard mutagen and could be considered as a potential preventive effect of cereals to DNA arising primarily by free radicals effect. The highest values of group and individual phenolics, antioxidant and antimutagenic activity were found in germs, bran, in buckwheat products and in coloured and raw rice. In flavoured cereal products addition of chocolate or fruit positively influences content of active phenolic substances as well as sugars, antixidant and antimutagenic activity. In a representative sample of Czech population, questionnairy study was performed to monitor interest in cereals and consumer preferences. The most of consumers consider cereals with chocolate flavour as less healthy than confirmed results of laboratory analyses. In this study some new food products were developed. Several types of model cereal products containing plant (fruit, vegetables) extracts were proposed. Extracts were added to cereals in freeze-dried and encapsulated form. The highest positive effect exhibited addition of local forrest fruit extract. Within preparation of encapsulated extracts several methods of preparing lipid or saccharides particles were also tested. The encapsulation efficiency of the methods and stability and size of particles were analysed. Optimal type of fortified cereal foods could be suggested based on the acquired results. Selected cereals were used as alternative carbon substrates (processed or raw) for the cultivation of microorganisms to produce enriched biomass usable in the feed industry. We can conclude that cereals in raw as well as processed form belong to universal foods and rich sources of biologically active substances. They can be processed by many ways. They can be used for direct consumption, as a part of new products and also undirectly as a substrate for feedstock.
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Characterization of cereal products with fruit component for baby nutrition
Pražáková, Jana ; Lichnová, Andrea (referee) ; Márová, Ivana (advisor)
Present bachelor thesis deals with the characterization of milk cereal products intended for baby food. The theoretical part focuses on the morphology of cereal grains, fortification, an overwiev of supplementary components used to fortification and their properties. For the practical part eight kinds of cereal dairy products of three different producers were chosen. In these products total polyphenols, total flavonoids, reducing and total saccharides and proteins were analyzed. The highest level of polyphenols was measured in product Sunar multicereal. The highest amount of flavonoids (more than 50 % of total phenolics) was found in Nestle fruit product. The highest level of total and reducing saccharides contained Nestlé honey flavour. High amount of proteins was found in products Sunar with multicereal flavour and pears with biscuits. Using HPLC/UV-VIS analysis vitamins C and E were determined. The highest content of vitamin C contained Nestlé with cookie lavor, while high vitamin E level was found in Sunar pear flavor and biscuits. Using HPLC/RI individual saccharides were examined. In all products high amount of lactose was found, mainly in the products of Sunar. Nestlé products contained mostly glukose, while in products Hami sucrose was detected as the most abundant saccharide.
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Fortification of selected cereal products
Hurtová, Jana ; RNDr.Renata Mikulíková, Ph.D. (referee) ; Márová, Ivana (advisor)
Present diploma thesis describes the study of bioactive compounds in the cereals. The work is focused on possible fortification of cereal products in order to increase nutritional value of final products which is reduced during the food processing and storage. Cereal grains are rich in several phenolic compounds, vitamins and minerals that reduce the risk of chronic diseases. The aim of this study was the preparation and analysis of model fortified cereals using lyophilized fruit originating from Czech Republic. A comparative analysis of content of bioactive substances in commercial and fortified products for children was performed too. The experimental part deals with a content of individual flavonoids by RP-HPLC/UV/VIS method, spectrophotometric determination of total and reducing saccharides and analysis of mono- and disaccharides by the HPLC/RI method as well. Differences in the content of individual flavonoids and saccharides after the application of acid hydrolysis of samples were investigated. The content of these compounds increased in most products because of their release from glycosidic forms. Presence of phenolics was confirmed in all analyzed cereals. Addition of 10% of lyophilized fruit/vegetable preparative (carrot, berries, apples) caused several fold increase of phenolics content in model mixtures. In commercially available cereal products there are relatively high differences in total phenolics content, proportionally to fruit component amount. The work included the spectrophotometric analysis of total polyphenols and flavonoids in a model physiological environment (artificial stomach juice) in which the hydrolysis of bound phenolic compounds occurred. The results of this study show that addition of lyophilized fruit seems to be a good way to increase the nutritional value and maintain the content of bioactive compounds in cereal products.
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Hodnocení kvality mléka pro výrobu sýrů
Dospivová, Kateřina
Milk can be described as a food that contains almost all the nutrients needed for life. The main component of milk is water and other components of milk include proteins, fats, carbohydrates. In smaller quantities also vitamins and minerals. With the advancement of modern technology, we are also offered new possibilities for the determination of individual parameters. These new methods are offer faster and it have more accurate results compared to the reference methods, which are for example the Kjeldahl method for protein, the Röse-Gottlieb method for fat and polarimetry for carbohydrates. Due to the deterioration in the dietary habits of an increasing proportion of the population, food fortification is being used to help maintain proper intake of essential nutrients and thus prevent various diseases. At the same time, new ways of preserving food are being developed that are more respectful of nature but also more beneficial to the consumer. These include, for example, edible packaging or treatment of raw materials other than by heat treatment.
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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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Pekárenské výrobky a těstoviny jako funkční potraviny
Lehkoživová, Victoria Patricie
The bachelor thesis focuses on bakery products and pasta and the possibilities of their fortification with substances of significant nutritional value for the human organism. In the first part the thesis focuses on the characteristics of the input raw materials, i.e., cereals. In the next part the production technologies and products are described. The literature search concludes with a discussion of important and nutritionally valuable substances, including their possible applications for fortification. Products Cereal products are an essential component in human nutrition. Therefore, they can be used very effectively for targeted fortification and increasing the nutritional value of products, They can contribute to to significantly expand the portfolio of functional foods. In the practical part, the 9 recipes of bakery products fortified with raw materials containing nutritionally valuable substances were developed. Their sensory acceptability was evaluated and the results were processed in tabular and graphical form.
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Fosfolipidy v potravinách
Zahradníková, Nikol
The main goal of this thesis is to highlight the benefits of phospholipids, which are currently underappreciated. The first part is devoted to a description of their basic characteristics, digestion and biological importance in living organism. Phospholipids differ in the benefits they provide to our organism. The next part focuses on the importance of their use in the food industry. In this sector, phospholipids are widely used as additives. Further, the work highlights the main sources and manufacturing animal and vegetable lecithin. Produced lecithin then undergoes a changing process of its chemical structure called modification. The modified lecithins produced this way have various applications in food. Subsequently, the thesis deals with methods for the determination of phospholipids in food. Specifically described is the most popular method for detection phospholipids in egg yolk and soy, HPLC-ELSD. The conclusion is devoted to the explanation of phospholipid fortification and functional foods. The increasing popularity of nanoliposomes in the food industry and the legislative requirements for lecithin are also mentioned.
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Fortification of bakery products with protein isolate from wheat bran
Bidmonová, Karolína ; Vítová, Eva (referee) ; Pořízka, Jaromír (advisor)
Proteins, as the major structural component of all cells and tissues, along with fats and carbohydrates, are a key macronutrient in human nutrition. An insufficient protein intake in the diet can lead to health problems and increasing protein malnutrition. Food fortification plays an important role in eliminating this protein deficiency. Wheat products, as a widely consumed food, seem to be a suitable commodity for protein fortification. Wheat bran was selected as a suitable source of protein due to its availability, protein content and relative simply method of a protein isolation. In the experimental part, the protein was extracted from wheat bran and used to prepare the mixtures. The mixture contained T530 flour and the 5%, 10% and 15% addition of the wheat bran protein isolate. From these mixtures, doughs were prepared and were subjected to chemical and rheological analysis. Finally, wheat baguettes with the addition of wheat bran protein isolate were made. The texture and taste properties of the baked products were verified by sensory analysis. The mixtures of flour and whey protein and a sample of unriched flour were also analysed to compare the results. Applied tests have shown that the addition of protein influences not only nutritional and chemical but also rheological properties. The addition of wheat bran protein isolate had a negative impact on the taste properties of the baguette Higher addition of BPI caused the increase of the bitterness of products. Taste optimization could be a topic for future study.
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