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Sensorial and analytical evaluation of cheese analoques flavour
Brabcová, Lenka ; Horváthová,, Viera (referee) ; Vítová, Eva (advisor)
The aim of the diploma thesis was to determine the influence of different kinds of fats on the content of aromatic active compounds and total flavour of processed cheese analogues. Samples of the cheese were produced by Tomas Bata University in Zlín from concentrated milk fat, butter, palm fat, coconut fat and sunflower oil. The aromatic compounds were isolated from samples of fats and processed cheese analogues via HS-SPME-GC method. A fibre with polar stationary phase CAR/PDMS was used for capturing of aromatic active compounds. In different contents, total of 32 aromatic compounds were determined. The cheese from concentrated milk fat and butter had the highest content and cheese from sunflower oil had the lowest. For determination of acceptability and flavour, the cheese analogues were sensory evaluated at the same time. Ordinal test, evaluation via scale and profile test were used. Cheese made from concentrated milk fat and coconut fat were always evaluated as the best, cheese made from sunflower oil were evaluated as the worst. Finally results between SPME-GC and sensory analysis were compared. It was stated that the kind of fat used for production of processed cheese analogues significantly influences the content of aromatic compounds and thus influences flavour of the cheese analogues.
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Characterisation of processed cheese analogues
Studýnková, Hana ; Buňka, František (referee) ; Vítová, Eva (advisor)
The aim of this diploma thesis was to identify and quantify the content of taste and aroma active compounds and to evaluate flavour of cheese analogue samples with various vegetable fats (coconut, palm, butter and mixed oils and butter) and differently matured Edam cheese using selected sensory methods. The samples were produced at Tomas Bata University in Zlín. Aroma compounds were extracted using SPME and assessed using gas chromatography. In total 43 compounds were identified, 14 alcohols, 9 aldehydes, 7 ketones, 8 acids, 5 esters and 1 terpene. Simultaneously the analogues were sensorially evaluated using scale, profile and ranking tests. The influence of storage time, type of fat and Edam cheese used on content of aroma compounds and sensory quality of analogues were evaluated. The cheese analogues with butter were sensorially evaluated as the best, with mixed oil as the worst. From the point of view of aroma compounds content, the significant differences between samples were evident. Using more matured Edam cheese, the content of aroma compounds declined, however, these samples were sensorially evaluated as better. The content of aroma compounds decreased also with storage time, which is more obvious in less matured Edam cheese. So all above mentioned factors influence the content of aroma compounds and thus the flavour of cheese analogues.
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Aroma profile of cheese analogues
Součková, Šárka ; Pšenáková, Ivana (referee) ; Vítová, Eva (advisor)
This Bachelor’s thesis deals with the issue of processed cheese analogues. It will explain what they are, their chemical composition and properties. The aim is to examine a number of cheese analogue samples with added various types of vegetable fats and identify and quantify the volatile aroma active substances present. Aroma compounds were isolated from samples using the Solid Phase Microextraction (SPME), a fiber with polar stationary phase (CARTM/PDMS) was used and the captured substances were then determined by gas chromatography. The evaluated cheese analogues varied in the type of the contained fat. In total 27 aroma active compounds in different amounts were identified. Cheese analogue with sunflower oil contained the most compounds (24) and the smallest number of aroma substances (16) has been detected in the cheese analogue with coconut fat. The highest concentration of aromatic compounds was found in the analogue with coconut fat and lowest in the cheese analogue with palm fat. Ethanol occurred in all types of analogues in the largest concentration. In conclusion it can be argued that the various analogues varied in the type and the amount of aromatic compounds, depending on the type of fat used.
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Characterisation of processed cheese analogues
Chlebcová, Lenka ; Buňka, František (referee) ; Vítová, Eva (advisor)
This diploma thesis deals with the topic of cheese analogues, their characterization and qualitative and quantitative analysis of processed cheese analogues for determination the taste and aroma active compounds. The overall character of processed cheese analogues is theoretically compiled in the introductory part. Their utilization, causes of the production, market introduction, technological production process and microstructure, including their comparison with classical processed cheese are given here. Various kinds of fats were used for production of analyzed cheese analogues, therefore commonly used ingredients for their production, their physical-chemical and sensory properties have been described. Specifically butterfat, milk fat, coconut fat, palm fat and mixed oil. Samples used for the practical part of the diploma thesis were made at Tomas Bata University in Zlín. In the experimental part the profile of aroma compounds in individual cheese analogues samples was assessed by SPME-GC analysis. In total 34 compounds were identified. The results were evaluated and compared, with emphasis put on the influence of storage, different fats, different maturity of Edam cheese on the content of aroma active compounds and on overall sensory quality of the analogues.
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Characterisation of processed cheese analoques
Svítilová, Lenka ; Horváthová, Viera (referee) ; Buňka, František (advisor)
The aim of this diploma work is to characterise processed cheeses and their analogues, to identify and quantify aroma active substances in the samples of cheese analogues, to evaluate their flavour using selected sensory methods and to compare the acquired results with the flavour of corresponding classic cheeses. The theoretical part is focused on general characteristic, classification, production technology of the processed cheeses and their analogues and on the list of aroma active substances occurring in cheeses. Furthermore, the summary of the methods suitable for sensory and analytic evaluation of cheese flavour and for the isolation of aroma active substances is given here. The samples of cheese analogues were made in Tomas Bata University in Zlín from coconut fat, butter, palm fat, milk fat and sunflower-seed oil. The classic processed cheeses were acquired commercially in the chain-store Billa. The aromatic substances were isolated and quantified using SPME-GC method, the fibre with the polar stationary phase CARTM/PDMS was used. Overall, 44 aroma substances were assessed: 9 aldehydes, 17 alcohols, 3 esters, 10 ketones and 5 acids. Classic processed cheeses contained the largest amount of aroma substances, Edam cheese, used for the production of cheese analogues, the smallest. Aroma compounds found in cheese analogues were then compared with raw materials used (Edam cheese and various fats), with the analogues produced last year and with classic processed cheeses. Finally, the results of the SPME-GC method and the sensory analysis were compared. It is possible to state that there are noticeable extensive differences between classic processed cheeses and cheese analogues, especially in taste.
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Influence of used oil on the composition and sensory quality of cheese analogues
Coufalová, Dominika ; Zemanová, Jana (referee) ; Vítová, Eva (advisor)
This master thesis deals with the production and characterization of cheese analogues with vegetable oil, specifically almond, hazelnut and walnut oils. The products were characterized by volatile compounds, fatty acids, antioxidant activity and sensory quality, and were compared with the standard product. The samples were described as soft white cheese. Volatile compounds were determined by gas chromatography-mass spectrometry. There were 29 compounds identified both in the standard cheese and the analogue with hazelnut oil, 31 compounds in the analogue with almond oil and 34 compounds in the analogue with walnut oil. The highest content of volatile compounds was found in the analogue with hazelnut oil, and the highest number of terpenes in the analogue with walnut oil. Fatty acids were converted into methyl esters after the extraction of fat by using mixture of organic solvents and then they were determined by gas chromatography with flame ionization detection. There were identified 11 saturated, 3 monounsaturated and 2 polyunsaturated fatty acids in all samples. The higher content was found in all cheese analogues compared to standard sample, moreover the content of unsaturated fatty acids increased. The highest content of polyunsaturated fatty acids was found in the analogue with walnut oil. The cheese analogues showed the higher antioxidant activity compared to standard cheese. A significantly higher content was found in the analogue with hazelnut oil. Oil addition decreased the sensory evaluation of consistence and flavour of samples. The standard cheese reached the highest score of overal acceptability among samples; the strongest nut flavour was described in the analogue with hazelnut oil. The results showed that the addition of oils increases the nutritional value of cheeses (higher content of unsaturated fatty acids, higher antioxidant activity), but reduces their sensory quality and overall consumer acceptability.
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Influence of oil used on composition and sensory quality of cheese analogues
Buldra, Martin ; Mikulíková, Renata (referee) ; Vítová, Eva (advisor)
This paper deals with the manufacture and characterisation of cheese analogues, which are products, where the milk components are totally or partially replaced by non-milk components. Model samples, edam type cheese and the analogue containing hazelnut oil, were manufactured using the standard way at Brno Mendelu. The main parameters chosen to describe the quality of samples were free and bound fatty acids, volatile compounds and sensory quality. The main aim was to judge the influence of added hazelnut oil on mentioned parameters. For the identification and semiquantification of volatile compounds HS-SPME-GC-MS method was used. Fat extraction from sample was made with a mixture of two solvents (diethylether, petrolether), fatty acids were identified and quantified by GC-FID, with their former acid transesterification using methanolic solution of BF3 as a catalyst. For sensory analysis of the appearance, colour, texture, aroma, taste and overall acceptance of the sample descriptive scales and comparison with standard were used, the structure was observed by electron microscopy. The results show that addition of hazelnut oil affects the sensory properties, ripening process (higher amount of volatile compounds, faster lipolysis), nutrition value (higher amount of unsaturated fatty acids), and the stability of the product.
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Composition of fatty acids in processed cheese analoques
Sůkalová, Kateřina ; Vespalcová, Milena (referee) ; Buňka,, František (advisor)
This thesis deals with the determination of fatty acids of processed cheese analogues. The aim is to identify and quantify the fatty acids in selected samples of cheese analogues. The introduction is a brief overview of the composition and properties of cheese analogues, technology and application options. The following describes the appropriate method for the determination of fatty acids in cheese and cheese analogues. Of these methods the largest part is devoted to gas chromatography, which is most frequently used method for detection of volatile fatty acids. Individual cheese analogues used for the analysis, contained various types of added fats. Specifically, the milk fat, coconut oil, sunflower oil, palm oil and butter. Samples of these fats were extracted and then converted to methylesters by methanol esterification with catalysis by potassium hydroxide. The most important fatty acids were identified and quantified in samples of cheese analogues using gas chromatography and compared with fatty acids of fats used for the preparation of these analogues are used.
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Aroma profile of cheese analogues
Studýnková, Hana ; Cetkovská, Jitka (referee) ; Vítová, Eva (advisor)
The aim of this bachelor thesis was to generally characterize cheese analogues and to identify the content of flavor and aroma active ingredients in chosen samples of analogues. Cheeses were manufactured at the Tomas Bata University in Zlín. The introductory section explains what generally processed cheeses and cheese analogues are, including their production. The importance, use and properties of cheese analogues are also described. The microstructure and changes during storage are also mentioned. Particular importance is devoted to their physicochemical and organoleptic characteristics. In the experimental section aroma active compounds of 3 types of processed cheese analogues containing various vegetable fats were identified and quantified. Cheese flavoring compounds were isolated by SPME method (solid phase microextraction) and assessed by gas chromatography. 5 groups of various aromatic compounds in different amounts: alcohols, ketones, aldehydes, fatty acids and esters were found. Finally, the cheese analogues and fats used were compared.
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The assessment of aroma compounds in processed cheese analogues
Hornáková, Miroslava ; Babák, Libor (referee) ; Vítová, Eva (advisor)
The aim of this work was to identify and quantify aroma compounds in samples of processed cheese analogues made at Tomas Bata University in Zlin. Analogues are processed cheese products in which lactic part is replaced by another component, either partially or completely. Market price is lower because of this replacement and that is why it is more attractive for the consumer. However, this substitution changes aroma, taste and texture, and also contributes to a reduction of the cholesterol content. Theoretical part is dealing with literature review of processed cheese analogues, focusing mainly on the composition, properties and production technology. In the experimental part 5 samples of cheese analogues made by using different types of fats (butter, apricot, grape, black currant and linseed oil) were analysed, simultaneously used oils were also analyzed. Aroma compounds were isolated by using SPME (solid phase microextraction) method and then determined by GC-FID. The most of aroma active compounds were identified in cheese analogue with patial substitute for grape seed oil instead of butter. The largest concentration of aroma compounds was identified in cheese analogue with patial substitute for linseed oil instead of butter. The black currant oil contained the most of aroma active compounds of all measured samples of oils. This oil also contained the largest concentration of aroma compounds.
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