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Application of herbal extract into suitable food product
Chmelařová, Adéla ; Saláková, Alena (referee) ; Vítová, Eva (advisor)
This master’s theses deals with a production and characterization of hard candies, a type of non-chocolate sweets. Methods of candies production were optimised with focus mainly on boiling temerature which significantly affects product consistency and stability. Production process optimisation was based on methods of sensoric analysis and Karl-Fishcher titration used to determine the water content in the product. Plant extracts Plectranthus amboinicus and Aronia melanocarpa which were applied to hard candies are rich source of bioactive compounds upon which prepared candies were characterised. Optimal conditions for candies production were – boiling temperature 155 °C, volume of citric acid 0,4 %, volume of Plectranthus extract 2 % and volume of Aronia extract 3 %. There were 42 volatile compounds identified in a sample containing 2 % of Plectranthus extract. Based on their content , the most significant compounds were carvacrol (8,44 %), carotol (1,47 %) and levomenthol (0,99 %). Total content of polyfenols was measured to be 7,10 ± 0,55 mgg-1 per 1 g of hard candy sample, antioxidant activity of a sample was 66,19 ± 1,80 gml-1. It was identified that 42 of volatile compounds were present inside the sample with 3 % of Aronia extract. The most significant being carotol (30,67 %), menthol (1,52 %) and thymol (1,39 %). The overall presence of polyphenols was measured to be 13,87 ± 1,12 mgg-1 per 1 g of the candy sample, the antioxidant activity of the sample was 115,00 ± 2,86 gml-1.
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Sensory quality of selected types of sweets
Michalíková, Veronika ; Němcová, Andrea (referee) ; Vítová, Eva (advisor)
This diploma thesis deals with the sensory evaluation of selected types of non-chocolate sweets. In the theoretical part the production technology of non-chocolate sweets is described, including raw materials needed. Furthermore, basics of sensory analysis with characteristics of sensory evaluation and selected sensory methods are mentioned. The experimental part deals with the sensory evaluation itself; the selected sensory methods were applied on samples of gummy sweets. Four colours/flavours (strawberry, orange, lemon, apple) from five producers were chosen for evaluation, together 20 samples. The aim was to assess the differences in sensory quality of samples of the same type from different producers. Untrained assessors, from Faculty of Chemistry BUT, were invited for sensory evaluations. Significant differences were found among the samples, glossy appearance and pleasant characteristic taste contributed to the positive evaluation, on the contrary the rigid texture, bland taste and odour and possible off-flavour contributed to the negative evaluation.
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Application of herbal extract to non-chocolate jelly sweets
Phi, Lan Anh ; Diviš, Pavel (referee) ; Vítová, Eva (advisor)
This master’s thesis focuses on optimization of application of herbal extracts and powder into jelly sweets and comparing them to commercial products with a same flavour. Prepared and commercial samples were then characterized in terms of volatile substances, total phenolic content, antioxidant activity and sensory quality. Volatile compounds were determined by HS-SPME-GC-MS method, a verification of validation parameters (limit of detection and quantification, repeatability, reproducibility, retention time, retention index) was part of the thesis. The total phenolic content was determined by Folin-Cicalteu’s spectrophotometric method, antioxidant activity by TEAC method and sensory quality by sensory analysis. Optimal amount of extracts and powders were selected based on the sensory analysis. For the preparation of extracts and powders were used aromatic plants lemon balm (Melissa officinalis) and ginger (Zingiber officinale). Optimal amount of extract addition was the concentration 15 %, by the next sensory analysis was determined 1 % addition of the powder for both herbs. There were 32 volatile compounds identified in a model lemon balm jelly, which of 4 were allergens (linalool, Z and E isomer of citral, citronellol, Z and E isomer of geraniol). Total phenolic content in the sample was 755,5 ± 14,3 gGAE g–1 and antioxidant activity was determined on a value 2,73 ± 0,13 10–3 mmolTE g–1. Commercial lemon balm sample contained 54 aromatic compounds from which were 5 allergens – limonene, linalool, Z and E isomer of citral, citronellol, Z and E isomer of geraniol. Total phenolic content was 695,5 ± 9,8 gGAE g–1 and antioxidant activity was 2,67 ± 0,05 10–3 mmolTE g–1. There were 26 volatile compounds identified in the model ginger jelly, which of 4 were allergens (linalool, Z and E isomer of citral, citronellol, (Z)-geraniol). Total phenolic content in the sample was 511,0 ± 12,3 gGAE g–1 and antioxidant activity was determined on a value 1,87 ± 0,16 10–3 mmolTE g–1. The first commercial ginger sample contained 55 aromatic compounds and 4 of them were allergens (limonene, linalool, citronellol, (E)-geraniol). Total phenolic content in the sample was 224,3 ± 20,2 gGAE g–1 and antioxidant activity was determined on a value 0,95 ± 0,24 10–3 mmolTE g–1. The second commercial sample contained 32 volatile compounds, which of were 4 allergens – limonene, linalool, Z and E isomer of citral and (E)-geraniol. Total phenolic content was 569,9 ± 23,2 gGAE g–1 and antioxidant activity of the sample was 3,48 ± 0,08 10–3 mmolTE g–1. In terms of sensory properties, the prepared samples which had balanced sweet and sour taste with pleasurable optimal herbal taste, were preferred by evaluators.
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Sensory evaluation of sweets
Boboková, Alexandra ; Burdějová, Lenka (referee) ; Vítová, Eva (advisor)
This bachelor thesis deals with a sensory analysis of a selected type of non-chocolate sweets – gummy jellies with sour coating. The theoretical part describes raw materials needed for the production of non-chocolate sweets, a list of non-chocolate sweets and their technological production are also mentioned. Sensory analysis and sensory evaluation methods are briefly described. The experimental part is focused on sensory analysis of selected yellow-coloured/lemon flavoured samples from five different producers. The samples were evaluated using a scale based on their appearance, colour, flavour, aroma and texture. Furthermore, the sensory profile and evaluation of aftertaste using time intensity methods were applied. Common consumers were represented by 20 untrained assessors from the Faculty of Chemistry of BUT. Bright colour contributed positively, while hard texture negatively to the overall evaluation of samples.
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Influence of aroma compounds on sensory quality of sweets
Motúzová, Eliška ; Zemanová, Jana (referee) ; Vítová, Eva (advisor)
This master´s thesis is focused on determination of aroma active compounds in non-chocolate sweets and their influence on sensory quality/flavour. The theoretical part describes production of non-chocolate sweets, characterizes aroma active compounds including allergenic ones, method for their determination by solid-phase microextraction and gas chromatography with mass detection. For experimental part were used as model samples gummy candies purchrased in regular market. Four flavors were used, specifically yellow (lemon), green (apple), red (strawberry) and orange (orange). The HS-SPME-GC-MS method was used to identify volatile aroma active compounds. To evalutate the sensory quality were used scales, a profile test, and a time course evaluation. Owerall 120 volatille compounds were identified including 8 allergens.
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Production and characterization of non-chocolate sweets with the addition of plant extracts
Knapovská, Pavlína ; Nábělek, Jakub (referee) ; Vítová, Eva (advisor)
This bachelor thesis deals with the production and characterization of plant extracts of green tea (Camellia sinensis) and sea buckthorn (Hippophae rhamnoides) and non-chocolate sweets – hard candies with the addition of plant extracts. These plants are characterized by a high content of bioactive substances, upon which the prepared extracts and candies were characterised. Determination of volatile substances by HSSPME-GC-MS, antioxidant activity by method with ABTS, determination of total phenols by Folin-Ciocalteu method and sensory analysis were performed. The produced sweets were then compared with similar commercial products. A total of 6 volatile substances were identified in the sample of hard candy with the addition of green tea extract, the antioxidant activity of the sample was determined to be 253,3 ± 0,9 µgml–1 and the total phenolic content was determined to be 0,49 ± 0,02 mgGAEg–1 per 1 g of candy. A total of 8 volatile substances were identified in the hard candy with the addition of sea buckthorn extract, the antioxidant activity of the sample was determined to be 206 ± 3 µgml–1, the total phenolic content was determined to be 0,51 ± 0,04 mgGAEg–1 per 1 g of candy. The obtained results show that the addition of extracts increases the nutritional value (higher antioxidant activity, higher content of phenolic compounds) of produced candy; from a sensory point of view, however, only samples with green tea were evaluated positively, the addition of sea buckthorn extract was not very attractive for consumers, they considered sweets with sea buckthorn to be too bitter.
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Study of selected technological properties of licorice mass
Gajdušek, Martin ; Vítová, Eva (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals with the study of selected technological properties of liquorice matter. By microscopic observation it was found that at a content of more than 10% of the boiled starch grains or more than 30% of the non-swollen grains, the mass does not achieve the desired properties for further processing. Technological loss during drying depends mainly on time, but also on location in the oven, both in height and space. The highest technological loss was achieved mainly in the highest positions in the oven. By liquid chromatography was determined 11.8% glucose, 9.2% fructose, 23.3% sucrose in liquorice mass prior to cooking; 11.9% glucose, 9.4% fructose, 22.6% sucrose in cooked matter; 12.7% glucose, 10.8% fructose and 20.1% sucrose in dried liquorice products.
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The content of aroma active compounds in sweets
Paulišová, Sabina ; Hrstka, Miroslav (referee) ; Vítová, Eva (advisor)
This bachelor thesis focuses on identification of aroma active compounds in selected samples of non-chocolate sweets. Based on the results obtained, the aromatic profile of the individual samples is compared. The theoretical part deals with aroma active compounds, legislation and technology of manufacturing non-chocolate sweets. Further experimental technique and the methods used in practical part, namely solid phase microextraction and gas chromatography with mass spectrometry detection are presented. In the experimental part volatile aroma active substances were identified in green colored jelly candy samples available in the common market. For this purpose, the HS-SPME-GC-MS method was used. The individual samples differed in type and number of volatile compounds, depending on the manufacturer. In total 72 different compounds, including 11 aldehydes, 14 alcohols, 27 esters, 1 heterocycle, 8 carboxylic acids, 6 ketones, 4 hydrocarbons and 1 sulfur compound were found.
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Sensory evaluation of model non-chocolate sweets
Malyszová, Markéta ; Mikulíková, Renata (referee) ; Vítová, Eva (advisor)
The aim of this bachelor's thesis was to implement a sensory analysis of model non-chocolate sweets of a selected type – specifically gummy jellies. The theoretical part deals with the characteristics of non-chocolate confectionery, information about their composition and properties and technological processes of production. Principle of sensory evaluation, including selected methods of this analysis are mentioned, too. The experimental part focuses on sensory evaluation of prepared gummy jellies. Several samples were made, which contained the addition of herbal extract, namely chokeberry and echinacea. The samples were evaluated using a scale based on their colour, aroma, and flavour. Furthermore, a profile test of tastes was applied, and their overall acceptability was evaluated. Untrained assessors, students from Faculty of Chemistry BUT, performed the sensory evaluations. The aim was to assess the influence of these herbal extracts on the sensory quality of the sample. The pleasant colour and taste influenced the positive evaluation the most. On the other hand, the faint aroma and bitter taste contributed to the negative evaluation.
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