|
|
Sensory evaluation of drinks enriched with extracts of herbs
Scholzová, Kristýna ; Pořízka, Jaromír (referee) ; Vítová, Eva (advisor)
This diploma thesis deals with sensory evaluation of herbal non-alcoholic beverages, being a part of a new product development. The theoretical part provides information concerning chemical composition, health effects, food applications and aroma compounds of the herbs of interest (peppermint (Mentha piperita), sage (Salvia officinalis), St. John’s wort (Hypericum perforatum) and lemon balm (Melissa officinalis). Another topic is a description of sensory methods, requirements and arrangement of the analysis, statistical methods, and also technological processes leading to herbal syrups and beverages production. The practical part comprises sensory analysis of a few, newly designed, formulas of one-component and two-component alcohol free herbal beverages. The sensory panel consisted of 40 students of master's and also doctoral study programme at Faculty of chemistry, University of Technology Brno. Four subsequent experiments are introduced, each of them consisting of a few sensory tests and including corresponding sensory forms attached. The sensory tests arrangement was based on currently valid Czech Technical Standards, using a ranking, descriptive, paired comparison, sensory profile testing and scaling methods. For the purpose of statistical evaluation, Friedman, Kruskal-Wallis, PCA and Faktor analysis were used. Level of abilities and sensory experience of panelists were found comparable to consumer testing. The results include sensory characteristics of all of the beverages tested. In general, the one-component beverages were preferred to the two-component beverages and the additive colouring with aronia concentrate wasn´t found any benefitial, from the sensory point of view. The consumer questionnaire proved all of the samples to be very promising, but based on the sensory results, we would consider the mint and the sage-mint beverages being the most potentialy applicable samples.
|
|
|
Complex characterisation of medical herbs and study of their utilization in food industry as a source of functional components
Burdějová, Lenka ; Kráčmar, Stanislav (referee) ; Šilhár, Stanislav (referee) ; Polovka, Martin (advisor)
Presented thesis deals with the complex characterization of extracts from medical plants using spectroscopic and chromatographic techniques, with emphasis on the influence of solvent, post-harvest treatment of the sample, location and year of production on selected parameters. Part of the work is devoted to application of selected extracts from medical plants in suitable form into beverages. The thesis is divided into two parts. At the first part of the work combination of electron paramagnetic resonance, ultraviolet visible spectroscopy, liquid chromatography and inductively coupled plasma optical emission spectrometry was applied for characterization of aqueous, ethanol and dimethylsulfoxide extracts from 10 selected medical plants, which were collected from two different locations during two years (2015, 2016) and post-harvestly treated by two ways (freezing, drying). In total, 39 parameters were determinated: namely total phenolic compounds content, total flavonoids content, 14 specific phenolic compounds, colour characteristics in the CIE L*a*b* system (L *, a*, b *, C*, h°, BI), radical-quenching activity using the cation radical of the 2,2'-azino-bis- (3-ethylbenzothiazoline-6-sulfonic acid), antioxidant/pro-oxidant activity using the spin trapping technique in the presence of 5,5-dimethyl-1-pyrrolin-N-oxide (DMPO)/potassium peroxodisulphate and content of 15 minerals (Al, As, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, P, Pb, Zn). The results confirmed that the studied parameters of medical plants are influenced by the extraction system, post-harvest treatment of samples, year of production, origin of samples (locality) and species composition. It has been shown that the type of extraction solvent significantly affects the composition of the extracts. On the basis of these analyzes, for food application – the isolation of the main functional components (phenolic compounds, flavonoids) –50% ethanol, post harvest treatment by drying and samples of Mentha piperita, Melissa officinalis, Hypericum perforatum and Salvia officinalis were selected. The second part of the thesis was focused on the application of selected extracts of medical plants to beverages (syrups). The above mentioned plants, 25% ethanol instead of 50% ethanol (due to the limitation of the ethanol content in final raw material), were selected for the application. At first, extraction of medical plants was optimized. Suitable ratio of material and solvent (1:10), extraction time (8 h) and herb absorbency (50–62 %) were determined. The prepared extract after filtration was applied to the syrup concentrate in different ratios to produce one-species syrups and further sensorially tested to select the suitable recipe, the best flavour and basis for the production of two-species syrups. The mint syrup was the most tasty and generally the most acceptable one-species syrup, and sage syrup was selected as the basis for two-species syrups. Further, the most appropriate recipes of the two-species syrups were chosen, the most sensorially acceptable one was selected and further tested if it would be appropriate to colour them. Preferentially, it has been found that it is not necessary to colour two-species syrups. On the basis of the sensory analysis, it has been found that peppermint and sage-peppermint syrups were the most tasty and acceptable syrups, which could be, after further testing, produced industrially to enrich the food market.
|
|
|
Aroma active compounds of selected types of medical herbs
Pecinová, Ester ; Diviš, Pavel (referee) ; Vítová, Eva (advisor)
This thesis deals with aroma active compounds of selected types of medicinal herbs, specifically lavender (Lavandula officinalis), peppermint (Mentha piperita), sage (Salvia officinalis), St. John’s wort (Hypericum perforatum) and hyssop (Hyssopus officinalis). In the theoretical part the single herbs were characterized including botanical description, chemical composition, medicinal properties, adverse effects and the practical use; aroma active compounds present in herbs are also emphasized. Based on the literature search, gas chromatography coupled with mass spectrometry as currently the most frequently used method, was chosen for the assessment of aroma compounds. Solid Phase Microextraction was used for isolation of volatile compounds from dried herbs. Within experimental part of the work selected parameters of the SPME-GC-MS method were optimized, aroma compounds in samples of herbs were identified, and twenty four suspected fragrance allergens due to the Regulation (EC) N° 1223/2009 were also identified and quantified. Overall 69 compounds were indetified together with 2 allergens in lavender, 59 compounds including 5 allergens in peppermint, sage contained 49 compounds with 4 allergens included, 41 compounds were identified in St. John’s wort including 4 allergens and finally 64 compounds with 4 allergens included in hyssop.
|
|
|
Srovnání antioxidačních vlastností a absorbce UV záření u extraktů vybraných bylin, Spiruliny a jejich směsí
Farinasso, Giulia
This study aimed to compare the antioxidant properties and UV radiation absorption of se-lected herbal extracts, blue-green algae spirulina extract and their mixtures. Extracts were ob-tained by ultrasound assisted extraction. The total polyphenol (TPC) and flavonoid contents (TFC) were determined, and the Trolox equivalent antioxidant capacity (TEAC) was meas-ured. The best antioxidant properties has been showed by C. officinalis individual extract and its mixture with spirulina. Additionally, the UV-absorbing substances at 355 nm were quanti-fied. The extracts from C. officinalis and S. nigra were further analysed for their rutin content by HPLC-DAD. The rutin content in S. nigra and C. officinalis extracts was found to be 1935,97 ± 98,39 μg.g-1 and 233,035 ± 8,839 μg.g-1 of dry weight of flos, respectively. The highest content of phenolic compounds was found in the S. nigra extract, and the highest total antioxidant capacity was determined for the C. officinalis extract. Pearson's correlation re-vealed that the overall antioxidant capacity and UV absorption results were significantly cor-related with the total phenolic compound content only for the elderflower extract. The syner-gistic effect of the herbs used in combination with spirulina was evaluated.
|
|
|
Škůdci volně rostoucích a pěstovaných hluchavkovitých léčivek
Kočicová, Anna
I observed pests of Lamiaceae medicinal plants by visual inspection in the growing season of 2022 on two experimental areas. The first experimental area was the MENDELU arboretum, the second was the garden in Boleradice. 30 species of plants were monitored in area 1 (MENDELU arboretum) and 10 plant species in area 2 (Boleradice). A total of 711 individuals, 31 pest species, from 4 orders and 18 families were detected. 20 species of insects belong to the order of Hemiptera, 9 to the order of Coleoptera, 1 to the order of Orthoptera, and 1 Dermaptera. Aphids were the most nu-merous taxon (137 individuals). The representation of polyphagous, oligophagous and monophagous phytophages was almost identical on both experimental plots: polypha-gous 56–57%, oligophagous 42%, monophagous 1–2%. Phytophagous species detected on Lamiaceae plants reached a higher occurrence in the MENDELU arboretum than in Boleradice. No phytophages were detected on Salvia splendens, Nepeta cataria, Galeopsis segetum and Ocimum basalicum. The most attacked plant was Ballota nigra (104 individuals and 14 species). The monitored Lamiaceae plants were not seriously damaged, and therefore it was not necessary to use any regulatory measures against pests.
|
|
|
Stanovení flavonoidních látek ve vybraných druzích léčivých rostlin používaných v potravinářství
Bačová, Romana
In plant and food research the functional significance of herbs, spices and other plants, including their components is very popular topic. Plant material contains many components that are beneficial to human health by reducing the risk of chronic degenerative diseases. It is necessary to define the individual substances to understand and explain their biological effects. The first part of thesis describes the selected plants (elderberry, nettle, marigold, milk thistle, sea buckthorn, sage, purple coneflower and thyme) and also describes their medicinal properties and uses. The second part of thesis deals with phenolic and flavonoid substances. In the third (experimental) part, of thesis there were qualitatively and quantitatively determined flavonoid compounds in selected plant species. For identification the technique combining liquid chromatography and mass spectrometry - HPLC/MS was used. Extraction was carried out by vortexing and Soxhlet method, using two different concentrations of metanol. These metods were then statistically compared.
|
|
| |
|
|
Herb garden and its connection with environmental education in kindergarten
BERANOVÁ, Iveta
The subject of the bachelor's thesis on the topic of "The herb garden and linking it to environmental upbringing at nursery school" is the introduction and definition of individual terms associated with environmental upbringing necessary for the draft and creation of a project on this topic and its actual realisation. The theory section of the thesis also presents an overview of legislation in the area of environmental upbringing and education introducing possible types of herb gardens, individual specifics of the cultivation of medicinal plants, their effects and safe use from the point of view of pre-school education. The practical section of the thesis consists of the stage of preparation, realisation and evaluation of the education programe. The stage of the preparation and realisation of the project contains activities associated with topics aimed at specific types of herbs in nursery school. The final practical area is the stage of evaluation rating the level of success of the actual practical teaching and suggestions for its improvement.
|
|
|
Allergics reactions to herbal medicines in childern
Meincke, Ricarda ; Pokladníková, Jitka (advisor) ; Marešová, Helena (referee)
Background: The use of herbal medicines in children and adolescents is continually on the rise. Contrary to popular belief, herbal products (HPs) are not always a safe alternative to conventional drugs and can cause a variety of adverse events such as severe and fatal allergic reactions. In regards to herbal medicine use in children, a recently published systematic review that searched PubMed, Embase, PsycINFO and AMED included 58 studies from 19 countries and found overall herbal lifetime use to be between 0.8-85.5 % and 2.2-8.9 % for current use. Unlike most synthetically produced drugs, the adverse event profile of such "natural" preparations in children has rarely been studied. To this date, effective systems that monitor adverse drug events (ADRs) and long term side effects associated with HPs are either non-existent or still developing in many countries. Due to insufficient and inconsistent ADR reporting, little is known about the ADR spectrum of herbals in pediatric patients. Awareness of the potential of HPs to cause ADRs, particularly in children and adolescents, needs to be increased and reporting to national pharmacovigilance centers (PVCs) reinforced. Objectives: This project analyzed the worldwide adverse event data for herbal drugs related to hypersensitivity reactions as recorded in...
|
|
|
In vitro cultures of medicinal plants - XI.
Sojková, Kristýna ; Tůmová, Lenka (advisor) ; Kašparová, Marie (referee)
In vitro cultures of medicinal plants - XI. Elicitation is one of the few strategies that can be used in enhancement of secondary metabolites production from explant cultures. The effect of abiotic elicitor (silver nitrate) on flavonolignan and flavonoid taxifolin production in suspension culture of Silybum marianum L. (Gaertn.) and on isoflavones production in suspension culture of Genista tinctoria L. was tested. Silver nitrate in various concentrations (5.887.10-3 mol/l; 5.887.10-4 mol/l; 5.887.10-5 mol/l) was used as elicitor. Content of secondary metabolites in suspension cultures was determinated by high performance liquid chromatography (HPLC). The samples were taken after 6, 12, 24, 48, 72 and 168 hours after elicitor treatment. The highest content of taxifolin production (0.02 %) in suspension culture of Silybum marianum L. (Gaertn.) after silver nitrate (5.887.10-4 mol/l) treatment and 72 h sampling was detected. The highest content of genistin (0.05 %) in suspension culture of Genista tinctoria L. was found after silver nitrate (5.887.10-4 mol/l) treatment and 48 h sampling. The highest content of daidzein (0.09 %) was detected after elicitor (5.887.10-4 mol/l) treatment and 168 h sampling.
|
guest ::
