• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 146
  • 98
  • 27
  • 22
  • 9
  • 4
  • 4
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 342
  • 105
  • 44
  • 39
  • 38
  • 32
  • 32
  • 31
  • 30
  • 30
  • 30
  • 25
  • 24
  • 23
  • 22
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

Antioxidační aktivita plodů různých kultivarů Sambucus nigra L. / Antioxidant activity of some cultivars of Sambucus nigra L. fruits.

Nehybová, Monika January 2014 (has links)
8. Abstract The fruit of the European elder, Sambucus nigra L., is used in therapy as a drug Sambuci fructus for its diaphoretic, diuretic and laxative effects. Cultivars of European elder are being studied for the use in the food industry and pharmacy. The fruit contains especially large amount of anthocyanins and flavonoids that are known for their antioxidant activity. The aim of this work is to measure the antioxidant activity of the drug Sambuci fructus and of the fruit of the European elder cultivars Samdal, Mammut, Sambo, Sambu, Sampo, Bohatka, Haschberg, Weihenstephan, Allesö, and Samyl. An extract containing anthocyanins was obtained from fruit by a process based on extraction of frozen material with acidified water at high temperature, followed by separation with polymer non-ionogenic polystyrene-divinylbenzene sorbent. The content of anthocyanins in the extracts was determined spectrophotometrically using a modified pH-differential method. The absorbance was measured along the range of 350 - 600 nm. The content of the anthocyanins was quantified in units of mg of cyanidin 3-glucoside in 1 ml of extract. The content ranged from 0.33 - 2.76 mg cyanidin 3-glucoside/ml of extract. The highest content was in the extract from the fruit of the cultivar Samdal and the lowest was of the cultivar Mammut....
212

Stanovení vybraných chemických parametrů plodů šlechtěných odrůd bezu černého / Determination of selected chemical parameters of fruits of cultivated elderberry varieties

Hamalová, Veronika January 2014 (has links)
In this thesis was determinated selected chemical and nutritional parameters in the wild elderberry and 17 cultivated varieties of elderberry. The fruits was provided by the Research and Breeding Institute of Pomology Holovousy Ltd. The theoretical part deals describes elderberry, chemical composition of elderberry, especially biological active substances and its using not only food industry. Closer attention has been focused on effect of saccharides, anthocyanins and methods of their determination, specially determination by HPLC. The experimental part describes the various methods of determination of selected chemical and nutritional parameters. Total dry matter, content of total polyphenolic compounds, monomeric anthocyanin pigment and antioxidant activity was defined in all varieties of elderberry fruits. For some varieties was defined total soluble dry matter, content of organic acids and saccharides by various methods. In the end was compared the values from different methods varieties.
213

Utah Red Raspberry Jam: The Effects of Formulation, Heating, and Time on Color, Flavor, Texture, and Antioxidant Capacity

Chase, Jennifer Leigh 01 December 2013 (has links) (PDF)
The amount and type of antioxidants present in raspberries is dependent upon cultivar, ripeness, and growing conditions. Previous research on raspberry jam has reported some color, antioxidant, and flavor loss after processing and storage, though it is unknown to what extent similar changes will occur in raspberries grown in Utah. Sugar concentration and heating temperature as well as storage time were evaluated in an effort to maximize color retention, flavor, antioxidant content, shelf life, and consumer acceptance of Utah-grown raspberry jam. Four types of jams were processed in two batches each: low-sugar (40-42 Brix) and typical sugar (65-68 Brix) at 85 and 95 C, from two separate farms in Utah. Oxygen Radical Absorbance Capacity (ORAC), total anthocyanin content (TAC), color, headspace, Brix, pH, consistency, and water activity were measured in fresh jam, and after one and three months of typical storage (dark, room temperature) to evaluate changes after storage. A sensory analysis compared three-month stored jam to fresh jam made from the same berry crop. ORAC significantly declined in all jams during storage. Fresh low-sugar jam was found to contain higher ORAC values than high-sugar jam after processing and after three months of storage. All jams retained their initial anthocyanins over the first month and significantly lost an average of 28.8% anthocyanins between months 1 and 3 of storage. Color loss was found to be less pronounced than anthocyanin degradation, though nearly all jams maintained initial L*, C*, and h* values over the first month then significantly decreased by the third month of storage. When comparing fresh and three-month jam, significant sensory differences were found in color, overall acceptability, flavor, and texture. All parameters scored higher for freshly-made jam, though three-month stored jam was still found to be acceptable to consumers. In summary, after three months of storage, significant nutrient quantity and sensory quality remains in Utah raspberry jam, despite significant declines in several assays and significant differences between treatments.
214

Characterization of juice and pomace from rabbiteye blueberries (V. virgatum) as affected by enzyme pretreatment, extraction process, and dehydration method

Eusse Durango, Jose A 09 December 2022 (has links)
Blueberry juice and pomace, enzyme pretreated (PT) or not, were extracted (EM) by steam and hot press methods. The pomace was further dried by convection oven (OD) or freeze-dried (FD). Juice yield was not affected by PT but was greater for steam extract (SE), due to water uptake. Carbohydrate and protein concentration were greater for hot-pressed (HP) pomace. Anthocyanins were not affected by PT or EM whereas phenolics were greater HP juice when subjected to enzymes. Dehydration method did not affect total phenolics when pomace was from HP but were higher in OD SE pomace. Enzymatic pretreatment had little influence on pomace quality, but HP pomace resulted in higher nutrients probably due to dilution. Oven drying resulted in slight degradation of pomace anthocyanins but not total phenolics. The dried pomace was shown to possess good nutrient quality and elevated functional components and can be used for value-added products.
215

Effects of Prunus cerasus L. Seeds and Juice on Liver Steatosis in an Animal Model of Diet-Induced Obesity

Martinelli, Ilenia, Di Bonaventura, Maria Vittoria Micioni, Moruzzi, Michele, Amantini, Consuelo, Maggi, Federica, Gabrielli, Maria Gabriella, Fruganti, Alessandro, Marchegiani, Andrea, Dini, Fabrizio, Marini, Carlotta, Polidori, Carlo, Lupidi, Giulio, Amenta, Francesco, Tayebati, Seyed Khosrow, Cifani, Carlo, Tomassoni, Daniele 20 April 2023 (has links)
The accumulation of adipose tissue increases the risk of several diseases. The fruits-intake, containing phytochemicals, is inversely correlated with their development. This study evaluated the effects of anthocyanin-rich tart cherries in diet-induced obese (DIO) rats. DIO rats were exposed to a high-fat diet with the supplementation of tart cherry seeds powder (DS) and seed powder plus juice (DJS). After 17 weeks, the DIO rats showed an increase of body weight, glycaemia, insulin, and systolic blood pressure. In the DS and DJS groups, there was a decrease of systolic blood pressure, glycaemia, triglycerides, and thiobarbituric reactive substances in the serum. In the DJS rats, computed tomography revealed a decrease in the spleen-to-liver attenuation ratio. Indeed, sections of the DIO rats presented hepatic injury characterized by steatosis, which was lower in the supplemented groups. In the liver of the DIO compared with rats fed with a standard diet (CHOW), a down-regulation of the GRP94 protein expression and a reduction of LC3- II/LC3-I ratio were found, indicating endoplasmic reticulum stress and impaired autophagy flux. Interestingly, tart cherry supplementation enhanced both unfolded protein response (UPR) and autophagy. This study suggests that tart cherry supplementation, although it did not reduce body weight in the DIO rats, prevented its related risk factors and liver steatosis.
216

Cofermentation, Post-Alcoholic, And Post-Malolactic Fermentation Blending Of Malbec, Merlot And Petite Sirah Wines

Vega-Osorno, Armando Arturo 01 September 2022 (has links) (PDF)
A two-year study was conducted to assess the effects of cofermentation on red wine varietals. During the winemaking process, wines can be made from two or more varieties by picking, crushing and fermenting them together, a practice known as cofermentation. They can also be blended either after the completion of alcoholic fermentation or after malolactic fermentation. In the first year of the study, two grape varieties, Merlot (Mer), and Malbec (Mal) were cofermented. On the second year, a third varietal, Petite Sirah (PS) was also studied. Cofermented wines containing every possible binomial combination of the varietals was made and one trinomial on 2019. The cofermented wines were compared to monovarietal wines and also to wines that were produced by blending either after alcoholic fermentation or after malolactic fermentation. The phenolic profile of the wines was followed from the onset of fermentation up to 36 months of bottle aging for the 2018 vintage and in the case of the 2019 vintage, up until 250 days after crushing. In 2018, cofermented wines and wines that were blended after malolactic fermentation had an anthocyanin profile that was more similar to Malbec than to Merlot, while the tannin profile was more resemblant of Merlot. In 2019 cofermentation improved the anthocyanin content when compared to post alcoholic and post malolactic blend only when the three varietals were cofermented. A sensory analysis with 10 trained individuals was conducted on the 2018 vintage. It was demonstrated that Malbec wines had a higher amount of red fruit aromas while Merlot wines were perceived as being more astringent. Cofermented and post malolactic fermentation blended wines were indistinguishable to panelists and blending after alcoholic fermentation produced wines that highlighted the individual varietal character.
217

Transport and Uptake of Anthocyanins in Gastric Tissue and Their Effect on the Gastric Inflammatory Response: Developing an in vitro Model Using the NCI-N87 Gastric Cell Line

Atnip, Allison A. January 2014 (has links)
No description available.
218

BIOCHEMICAL AND COLORIMETRIC STUDY OF FLOWER COLOR IN PHLOX SPECIES

Bohorquez-Restrepo, Andres 19 May 2015 (has links)
No description available.
219

Comparison of Consumer Acceptance, Physico-chemical Properties, and Bioactive Delivery of Blueberry Extract and Whole Blueberry Powder Confections

Myers, Meredith R., Myers 08 October 2018 (has links)
No description available.
220

Nutritional Value of Spent Hibiscus Calyces and Assessment of Consumers' Knowledge and Perception of Hibiscus Products for the Promotion of their Consumption

Ndiaye, Oumoule 09 November 2021 (has links)
Hibiscus calyces have anti-inflammatory effects, reduce metabolic risk factors, and act as a prebiotic in the human gut. Bioactive compounds in hibiscus include dietary fiber, polyphenols and vitamins and hibiscus calyces have a well appreciated flavor. Preparation of juice from hibiscus is done using hot or cold aqueous maceration procedures. When hibiscus beverages are made, the remaining biomass, the spent calyces, is discarded. Little information is available on the composition of the spent calyces. To determine whether the spent calyces have potential value, it is important to evaluate the composition of major bioactive elements and other potentially valuable components like aromas. The overall goal of this work was to determine if hibiscus spent calyces have components that would be of nutritional value, and to investigate consumer interest in hibiscus consumption in the U.S. The first objective was to measure the contents of sugar, fiber, anthocyanins, other phenolics, vitamin C, and organic acids (hibiscus/garcinic, citric, succinic, fumaric acid) in spent calyces. The second objective was to identify and quantify flavor compounds in the spent calyces. The third objective was to assess American consumers knowledge and perception of hibiscus products. Cold and hot aqueous extractions were carried out on whole calyces of red and white hibiscus using a calyces:water ratio of 1:15. The spent calyces were freeze-dried and analyzed for sugar, fiber, anthocyanins, total phenolics, vitamin C, organic acids and flavor compounds and compared to whole calyces. Soluble and insoluble dietary fiber were measured using sequential enzymatic digestion and gravimetric filtration according to the AOAC method. HPLC was used to determine sugars, anthocyanins and vitamin C, acids. UPLC to identify polyphenols and GCMS with SPME to identify and quantify aroma compounds. Results of the survey show that most of the American consumers who participated in this study have consumed hibiscus products before and were aware of the health attributes of hibiscus products. The most liked products were tea and juices. Main reason for hibiscus consumption was in order: taste, health, flavor, and trend. The health statement provided to the participants of the survey did not affect their willingness-to-pay (WTP) for hibiscus beverages. Spent calyces contained significant amounts of sugars, anthocyanins, total phenolic, organic acids, vitamin C, dietary fiber, and aroma compounds. More fiber was found in the spent calyces than in the raw ones; volatiles profile and phenolics profile were similar to those of the raw calyces. These important nutritional compounds make hibiscus spent calyces useful as a functional ingredient in food products or for producing nutraceutical products. Use of spent calyces will increase value of hibiscus products benefit to both consumers and industrials and help reduce economic and environmental issues related to food waste management. / Doctor of Philosophy / Hibiscus is a plant native to the tropics. Two types of hibiscus plants exist: red and white; both have been used in traditional medicine, in cooking and for making beverages. Both share the following characteristics: sour taste, pleasant natural flavor, refreshing properties, and high content of elements such as dietary fiber and antioxidants that promote health. Hibiscus calyces are reported to have potential to retard early aging, fight against inflammation, and reduce metabolic risk factors (diabetes, obesity, and high blood cholesterol). Fiber acts as prebiotic in the human gut and therefore facilitate bowl movement. Hibiscus calyces are consumed in the forms of tea, juice, smoothies, jam and marmalade and are highly appreciated by consumers. However, despite these attributes and possible uses, the whole calyces' byproducts, spent calyces, are discarded after obtaining the juice from the whole calyces. They are considered as a waste product. As hibiscus is mostly produced and mainly known in places like India and Africa, we were interested in learning about American consumers knowledge and perception of hibiscus products. The purpose of this work was to evaluate the spent calyces' major components and investigate American consumers' knowledge of hibiscus. Red and white hibiscus were obtained from Senegal. Nutrients in spent calyces obtained from cold or hot aqueous extraction of each type of hibiscus was determined. The waste calyces obtained from both hibiscus types contain significant amounts of fiber, sugars, acids, anthocyanin pigments and other phenolic compounds. Phenolic compounds were idenuutified and many are known to have positive effects on health. Many aroma compounds were present in the waste product as well. The results revealed that most American consumers were familiar with and had consumed hibiscus products before. They were most interested in teas followed by juice. Taste was the prime reason why they consume hibiscus products then health properties. participants` willing to pay (WTP) did not increase after they were provided with information on hibiscus health benefits. Hibiscus spent calyces could be used for new food products manufacturing as they can add value to our diet and help consumers stay healthy. The findings can help in the promotion of hibiscus products consumption and commercialization and in reducing food waste.

Page generated in 0.061 seconds