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Jelly candies with the addition of bilberry (Vaccinium myrtillus) extract
Knapovská, Pavlína ; Pořízka, Jaromír (referee) ; Vítová, Eva (advisor)
This thesis deals with the application of bilberry fruits (Vaccinium myrtillus) and their extract to jelly candies and the subsequent characterization of these candies in terms of volatile compounds, total phenolic compounds and anthocyanins, antioxidant activity and sensory quality. The volatiles were determined by headspace solid-phase microextraction coupled to gas chromatography with mass spectrometry and standard spectrophotometric methods were used for the determination of bioactive compounds. Total phenolic content was determined by the Folin-Ciocalteu method, antioxidant activity by the TEAC method and total anthocyanin content by pH differential analysis. The sensory quality of the samples was evaluated using unstructured graphical scales. The preparation of the bilberry extract was optimized on the basis of total phenolic content and the following conditions were selected as the optimal: a weight of 1000 grams of bilberries per litre of water, a temperature of 50 °C, and an extraction time of 2 hours. The optimum additions to candies were selected, by sensory analysis, as 25 wt. % of extract and 15 wt. % of bilberries. A total of 45 volatile compounds were identified in the candy with bilberry extract, the most abundant being (E)-9-hexadecen-1-ol (22,7 %), furfural (10,9 %) and 2-ethylhexan-1-ol (10,0 %). The total phenolic content was 1141 ± 11 gGAE · g-1, the antioxidant activity was 660 ± 66 gTE · g-1 and the total anthocyanin content was 418 ± 23 gC3G · g-1. A total of 40 volatile compounds were identified in the candy with bilberry and the most abundant were linalool (22,7 %), (E)-9-hexadecene-1-ol (16,1 %) and 2-ethylhexan-1-ol (8,4 %). The total phenolic content was 1735 ± 56 gGAE · g-1, the antioxidant activity was 1109 ± 32 gTE · g-1 and the total anthocyanin content was 745 ± 23 gC3G · g-1. With the addition of both the extract and the bilberries, the candies showed a significant increase in bioactive and volatile compounds content, and the colour and flavour of the enriched samples were positively evaluated, thus improving their overall acceptability.
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Optimizing the production of non-chocolate sweets with the addition of Filipendula ulmaria extract using various sweeteners
Malyszová, Markéta ; Diviš, Pavel (referee) ; Vítová, Eva (advisor)
The aim of this master's thesis was to optimize the production process of jelly candies using various alternative sweeteners and subsequently adding herbal extract of meadowsweet, achieving not only better nutritional properties but also enhanced sensory characteristics of the final product. Sensory analysis was utilized to determine the ideal combination of sweetener type and amount, which most closely aligns with consumer preferences for sweetness and texture, while maintaining a low energy component content. Based on these criteria, maltitol was selected as the sweetener in a 50% w/w solution. The study also focused on optimizing the addition of Filipendula ulmaria extract to the candies made with the "ideal" sweetener. Again, using sensory analysis, the optimal concentration of the extract and the type of gelling agent were selected to achieve the desired consistency, taste, and other sensory parameters that make the product attractive for consumers. Following these experiments, the ideal values were determined to be 50% w/w for sweetener, a 5 % addition of Filipendula ulmaria extract, and the use of gelatin as the gelling agent. Subsequently, a chemical analysis of the produced samples and meadowsweet extract was also carried out. Identification and quantification of volatile aromatic compounds were performed using the HS SPME GC-MS method, which identified 39 different substances, predominantly from the group of alcohols and aldehydes. To determine the total content of phenolic compounds, the Folin-Ciocalteu spectrophotometric method was used, and the pH differential method was employed to determine the content of anthocyanins. The total content of phenolic compounds in the extract amounted to 1418.16 ± 6.56 gml-1, and the total anthocyanin content was determined to be 249.19 ± 27.40 gml-1. Antioxidant activity was tested using two methods, TEAC and DPPH. The results of the antioxidant activity measured by the DPPH method were higher, confirming the greater robustness of this method. However, both tests confirmed the antioxidant activity of the tested samples. Finally, the antimicrobial activity of the samples was tested using the diffusion well method against strains of Bacillus cereus and Escherichia coli. The samples exhibited antimicrobial activity against both tested microorganisms, but showed more effective action against Bacillus cereus, which may be due to the simpler structure of their cell wall.
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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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