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Evaluation of selected bakery products based on different processing technology and recipe
HRDLIČKOVÁ, Vanda
Together with the emerging trends of healthy lifestyle, organic products and organic farming, the domestic production of various food products and the fermentation process are becoming increasingly more important for the population. Fermentation technologies cover a wide range of products in the food industry or in other fields. The first references mentioning fermentation of flour and water (i.e. sourdough) date back to 1500 BC in ancient Egypt, and despite new doughraising technologies such as baker's yeasts, baking powder and baking soda, it is sourdough starter that is becoming popular not only for bakers but also for the whole population. The aim of this thesis was to evaluate the effect of the sourdough starter used on the quality of bakery products. The first part is devoted to a theoretical overview concerning fermentations, cereals, bakery products and their production technologies. The second part of the thesis was practical, where samples of the produced bakery products were evaluated by two methods based on the baking experiment, i.e. sensory analysis and physicochemical analysis. The thesis was also complemented by a questionnaire survey. Significant differences were found in the physicochemical parameters of yeast-leavened and sourdough leavened loaves of bread (acidity, bulk density, ageing symptoms). A positive effect of leavening was also demonstrated in the sensory analysis, in which the sourdough loaves of bread were rated better by the evaluators than the leavened bread samples.
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Pretreatment of polysaccharide waste materials to maximize of hydrolysis products
Myslivcová, Pavla ; Trachtová, Štěpánka (referee) ; Babák, Libor (advisor)
This thesis deals with study of the polysacharidic waste material pretreatment in order to maximize the hydrolysis products. It has been chosen a pastry as a waste material, specifically rolls and bread. Pastry was pretreated by milling and 15% w/v suspension of pastry in the water was prepared. Then several types of hydrolysis were performed with suspensions. Products of hydrolysis were characterized by spectrophotometric method of Somogyi-Nelson and efficiency of hydrolysis was compared. Three acids (H2SO4, HNO3, HCl) and two alkalis (NaOH, KOH) in three various concentration were used for the chemical hydrolysis. Microwave and ultrasound were chosen for the physical hydrolysis.
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A study of the possibility of waste pastries using for the bioproduction of selected metabolites
Hudečková, Helena ; Vránová, Dana (referee) ; Babák, Libor (advisor)
The aim of this diploma thesis was to study the possibility of using waste bread to bioproduction of selected metabolites. As bakery waste was used waste bread that came from coffee-house “Zastávka”. Bread was pre-treated by grinding into small particles and then it was made to form 15% w/v suspension, which was subjected to enzymatic hydrolysis. For the hydrolysis has been used the -amylase for liquefaction of the substrate and that was followed by a glucoamylase which sacharificated the substrate. There have been several methods of hydrolysis from which was chosen the optimal method for pre-treatment of the substrate prior to fermentation. The effectivity and a process of hydrolysis were determined spectrophotometrically by Somogyi-Nelson method. Final yields of glucose from hydrolysis were determined by HPLC method. Enzymatic hydrolysis was followed by fermentation, which was carried out in two ways, namely by adjusting the pH of the hydrolyzate to pH 5, and without pH adjustment. During the fermentation was carried out sampling in which was determined the content of glucose, glycerol and ethanol by HPLC method. The yeasts Saccharomyces cerevisiae were used for the fermentation which was performed at 30 °C. High yield of glucose was achieved by hydrolysis in two steps (70,28 gl-1), but for the fermentation was used mixed hydrolysis (second method of mixed hydrolysis) with yield 67,94 gl-1. High ethanol yield was achieved during fermentation without treatment pH, namely 31,5 gl-1.
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Design of bread maker
Pavla, Jozef ; Sládek, Josef (referee) ; Machálek, Róbert (advisor)
This thesis dedicates about designing a modern bread-machine, which is becoming more common in our households. It is simultaneously developing new culture besides formation and exchanging own experiences and recipes. The conclusion, respects all the followed aspects and requirements. It is possible to pack it into more compact size easily transported. The final design also meets the controlling requirements as well as it’s unconventional solution helped to stand out of conventional solutions.
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Evaluation of the sensory quality of bread
Mahdalová, Martina ; Vránová, Dana (referee) ; Vítová, Eva (advisor)
This work deals with the evaluation of sensory quality of selected samples of bread. The samples of bread were bought in TESCO Stores a. s. ČR in Brno. Totally five samples were evaluated, two of them were rye-wheat and three of them were wheat-rye. All products were packaged and sliced. Purchased samples were subjected to sensory evaluation by the ranking test and scale tests. The assessors judged three main organoleptic properties of bread – taste, odour (aroma) and texture. The results were written down in the questionnaires and consequently graphically and statistically evaluated. The assessors which took part in sensory analysis were chosen from students of Faculty of chemistry BUT.
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A strategy of acrylamide elimination in cereal foods
Belková, Renáta ; Ing.Kristína Kukurová, Ph.D. (referee) ; Ciesarová, Zuzana (advisor)
Acrylamide is a carcinogenic substance generated in heat processed food stuff, where the temperature increases over 120 °C. The main acrylamide precursors are carbonyl compounds and the amino acid asparagine. In this diploma work, possible elimination strategies were observed in a bread matrix with an addition of inorganic salts into the basic powder formulation for home bread making. Samples were analyzed from the point of view of acrylamide content as well as their physico-chemical properties and sensory evaluation too. Results show, that the addition of inorganic salts hasn`t expected considerable elimination impact as in the case of model samples. It has been shown the importance of fermentation process, whereas was the amount of acrylamide in bread without yeast added almost 14times higher. The addition of CaCl2 in bread mixture improved the organoleptic quality of final product, as proved in sensory evaluation with simultaneus positive effect on acrylamide reduction in bread.
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Design of Bread Cutting Machine
Zbořil, Jan ; Rajlich, Jan (referee) ; Rubínová, Dana (advisor)
The topic of my bachelor thesis is designing a self-service bread cutting machine. The project is focused on improving the esthetical side of the machine, but also comes with inventional ergonomic and technological solutions concerning the operation of the machine and its cutting system.
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Use of alternative plant flours for bread production
VÍTKOVÁ, Věra
This thesis is about importance of bread in diet, nutritional composition and the result of excessive at the human health. Part of the text deals with materials which are important section of research focused at enrichment of bread without negative effect on technical properties of dough. Is an effort to keep original sensory properties. Practical part deals with hemp, gourd, milk thistle and flax flours. This material was used in 5 or 10 % for baking 17 breads following the standard recipe. These breads were dried and grinded. Grounded breads were subjected to analysis of polyphenol content, antioxidant activity and nitrogen substance content. All breads containing oilseeds had better nutrition properties. There was not a problem with technological properties during dough processing.
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Quality assessment of gluten-free foods with a focus on pastries
ZIMMELOVÁ, Helena
The topic of this thesis is the production of gluten-free bread from naturally gluten-free flour, which will be enriched with suitable additives that will increase antioxidant activity and naturally effect on the structure of the pastry, so it will meet the sensory requirements of final consumers. The literary part define, which proteins can be found in cereals, what does the gluten means, its function in the pastry and which diseases can cause. In connection with these diseases, a gluten-free diet for improving the patient's health and suitable foodstuff are briefly described. The literary part is concluded with the theory of sensory evaluation. The practical part deals with the production of naturally gluten-free breads enriched with ingredients from kitchen onions (Allium cepa L.) and subsequent sensory evaluation of this bread. Selected statistical procedures were used to obtain, processed and evaluated data. Antioxidant activity was also monitored and evaluated. By using texture-meter was find out, what effect has additives on aging of gluten-free bread.
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The Institution of the Eucharist in context of the miraculous feeding narratives
Revenda, Václav ; Brož, Jaroslav (advisor) ; Scarano, Angelo (referee)
The Institution of the Eucharist in context of the miraculous feeding narratives The Diploma thesis "The Institution of the Eucharist according to Mark in context of the miraculous feeding narratives" studies lexical, intertextual and biblical-theological relations between the Marcan account on the institution of the Eucharist (Mark 14:22- 25) and two miraculous feedings (Mark 6:35-44, 8:1-10) during Jesus' public ministry. The study exposes that in context of the Gospel of Mark all three indicated pericopes are in a key position and significance in Jesus' mission a reveal an essential aspect of the revelation and of the coming of the Kingdom of God. Beside applying the method of continuous commentary of the mentioned texts the work applies a study of parallel synoptic pericopes, referential texts in the Old Testament and an analysis of biblical- theological themes in canonical relation. A special attention is given to different aspects of the Jewish celebration of the Pesach meal and its relations to the Christian Eucharist, which has its origin in Jesus' Last Supper and finds an echo in both Marcan narratives on miraculous feeding of great amount of people as well. 81
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