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Fermentation and Supercritical Extraction Studies of Açaí BerryAyala, Rosanna Iris 01 January 2012 (has links)
The açaí berry has grown in popularity for dieters and the health conscious. The berry contains high levels of antioxidants. The main anthocyanins are cyanidin-3-rutinoside and cyanidin-3-glucoside. The berries also contain vitamins and nutrients that help boost energy and alertness, and fatty acids that help maintain normal cholesterol levels. As a result of the health benefits of the constituents, the berries are chosen for obtaining the active ingredients by extraction.
The solids left over after extraction still contain nutrients and useful components. There is a possibility of fermenting this residual and creating an açaí berry wine. Açaí berry wine is another new product on the market. The extracts and the wine are analyzed using Fourier transform infrared spectroscopy (FTIR). In an effort to utilize every part of the berry, the residual from the extract is also successfully fermented.
Pilot plant studies are conducted utilizing supercritical carbon dioxide, an ethanol entrainer to increase its solubility, and subcritical water to extract components from freeze dried açaí berry. There is much potential and flexibility in the process, which effectively extracted lipids from the berry leaving behind anthocyanins without solvent residue.
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Antioksidacinio poveikio preparatų su juodųjų serbentų (Ribes nigrum L.) uogų ekstraktu tyrimas ir vertinimas / Development and evaluation of antioxidant preparations containing black currant (Ribes nigrum L.) berries extractKasparavičienė, Giedrė 26 January 2006 (has links)
Growing numbers of morbidity and mortality due to the cancer and coronary heart disease is recognized as the increasing challenge in the world. The initial stage of these diseases, early diagnosis and treatment are the main objectives of current researches. According to Lithuanian Health Information Centre morbidity and mortality due to these diseases in Lithuania exceed average of European Union. The oxidative stress occurs in cells as a result of normal physiological processes and environmental interactions, and the complex antioxidant defense system are of particular importance in protecting biological systems against oxidative damage by free radicals. Recently polyphenols and anthocyanins containing foods and preparations have attracted attention due to their health promoting benefits. Anthocyanins make one of the main groups of flavonoids, and represent polyphenolic compounds, that are found in vegetables and fruits, particularly in berries. An important effect of anthocyanins is the scavenging of oxygen-derived free radicals. They can interfere with few different free radical-producing systems, and can increase the function of the endogenous antioxidants.
The aim of the research is to choose sources for the products with antioxidant activity from plants cultivated in Lithuania, evaluate quality and antioxidant activity of black currant, red currant and chokeberry products, to develop and evaluate technologies of phytopharmaceuticals with antioxidant activity... [to full text]
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Proanthocyanidins, anthocyanins and phenolic acids in food barleys of diverse originHambira, Chipo 11 January 2010 (has links)
Phytochemicals found in grains complement those found in fruits and vegetables. These phytochemicals, though minor compounds, contribute to the antioxidant properties which are related to the health benefits associated with the consumption of whole grain. In this thesis project, nine barley genotypes of diverse origin namely CI2230 from Nepal, CI1248 from Israel, 3 Peruvian genotypes; Peru 3, Peru 16 and Peru 35, Hokuto Hadaka from Japan, EX116; a cross between Moroccan and Canadian genotype, EX83; a cross between two Canadian genotypes and EX127; a cross between Canadian and German genotypes were studied. The genotypes were categorized based on appearance into purple, black and yellow grains. Phenolic acids and flavonoids were identified and quantified in these diverse genotypes using HPLC-ESI-MS analysis. The main classes of dietary flavonoids studied in the barleys were anthocyanins and flavan-3-ols. Phenolic acids were identified and quantified (p-coumaric, ferulic, sinapic, caffeic, vanillic). Three ferulic acid dehydrodimers (8-0-4â DFA, 8-5â benzofuran form and 5-5â DFA) were also identified. The most abundant dimeric flavan-3-ols were procyanidins B3 and prodelphinidin B3. The monomeric unit, (+)-catechin, was the most abundant while catechin glucoside (m/z 451) was also identified. Among the Peruvian genotypes, Peru 16 and Peru 35 exhibited relatively high levels of total PA content. Total phenolic content and antioxidant activities of methanolic, acetone and alkali hydrolyzed extracts of the nine barley genotypes was determined by the Folin- Ciocalteau assay, DPPH radical scavenging assay and oxygen radical absorbance capacity (ORAC assay).The acetone extract exhibited the highest antioxidant capacity using all the methods of analysis. Furthermore, dark colored grains were found to exhibit higher contents of phenolic compounds. The phenolic acids, PAs and anthocyanins identified and quantified had significant contribution to the overall antioxidant capacity of the barley whole grain. Four hull-less genotypes namely CI2230, EX127, CI1248 and Peru 35 were further partially sprouted to establish the effects of sprouting on phenolic acid composition. Partial sprouting was observed to significantly increase the soluble conjugated phenolic acids. The barley genotypes studied were found to contain different quantities of phytochemicals and had high proanthocyanidin content thereby rendering them as alternative sources of antioxidants. Barley sprouts present a possible novel food ingredient with improved properties such as phenolic acid composition and other benefits such as easier incorporation into food products under development.
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Analysis of Antiviral and Chemoprotective Effects of Strawberry AnthocyaninsWillig, Jennifer A. 01 January 2013 (has links)
This study investigated the antiviral, chemoprotective and proliferative effects of strawberry anthocyanins on herpes simplex virus type-1, cancerous cell lines HT-29 and AGS, and normal cell lines Hs 738.St/Int and CCD-18Co. Antiviral properties were measured by infecting vero cells from adult grivet (Cercopithecus aethiops) with herpes simplex virus type-1 (HSV-1) and treating with a concentration of 1.25-20 µg/mL of strawberry anthocyanins. Infectivity and replication were quantified for herpes simplex virus type-1 using the direct plaque assay and reporting PFU/mL. Strawberry anthocyanins (>20 µg/mL) inhibited the herpes simplex virus infectivity in vero cells by 100% (p<0.05). Strawberry anthocyanins at concentrations of 5, 10 and 20 μg/mL were reduced to 75.36, 57.98, and 31.46 percent of the control (100%) (p<0.05).
Chemoprotective and proliferative effects of strawberry anthocyanins were analyzed for the human cell lines AGS, Hs 738.St/Int, HT-29, and CCD-18Co at a concentration of 25-200 µg/mL and quantified using the sulforhodamine-B assay. Growth inhibition occurred at a level of ≥87% for treatment concentrations 100 and 200 µg/mL for the cancerous AGS and HT-29 cell lines (p<0.0001). Proliferation rates for the normal Hs 738.St/Int and CCD-18Co cell lines increased at all treatment concentrations of 25-200 μg/mL (p<0.0001); suggestingthat the observed proliferative activity may be associated with anthocyanin treatment.Strawberry anthocyanin treatment concentration worked in a dose dependent manner for the HSV-1 and the cancerous AGS and HT-29 cells. The caspase-3 assay was performed to demonstrate potential mechanism of action and confirmed thatanthocyanin treatments play a role in apoptosisby the up regulation of caspase-3.Significantdifferences were seen between the growth characteristics of cancerous cell linescompared to their equivalent normal cell lines (p<0.0001).
In summary, the antiviral findings suggest that strawberry anthocyanin extracts could be an effective topical treatment and/or prophylactic agent for oral herpetic infections (HSV-1). Also, the in vitro chemoprotective effect of strawberry anthocyanins found may be relevant to in vivo work in the future because when anthocyanins are consumed in the diet they come in direct contact with the gastrointestinal tract and may provide chemoprotection upon contact with the stomach and gastrointestinal tract’s epithelial cell layer.
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CONCEPTUALIZING AND IMPROVING RED WINE GRAPE CULTIVARS GROWN IN KENTUCKYSimson, Matthew 01 January 2011 (has links)
Wine sensory attributes are associated with quality of wines. Cabernet Franc did not possess good coloration of its wine. Therefore, in the 2009 and 2010 growing seasons, studies including the sampling of four red wine grape cultivars from the end of flowering throughout the rest of the season and applying treatments to Cabernet Franc grapevines at veraison were commenced to address suitability and color enhancement, respectively. The study examining Cabernet Franc, Cabernet Sauvignon, Chambourcin, and Norton looked at sampling their grapes at two-week intervals from times post-flowering to understand the demands of each cultivar during key stages of berry development, in particular berry maturation post-veraison. The French-American hybrids Chambourcin and Norton were found to accumulate high levels of anthocyanins, also termed high cultivar performance, while the Vitis vinifera L. cultivars of Cabernet Franc and Cabernet Sauvignon remained stable in their anthocyanin content post-veraison. The results of the treatments applied to Cabernet Franc as a possible exogenous amelioration for anthocyanin pigment deficit in this cultivar support use of treatments for improving coloration in Cabernet Franc in Kentucky.
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Identification and Antioxidant Properties of Phenolic Compounds during Production of Bread from Purple Wheat Grains and Investigation of Bread Extracts after Simulated Gastrointestinal DigestionYu, Lilei 27 October 2014 (has links)
Content of free- (FPC) and bound- phenolics (BPC) significantly (p<0.05) increased during mixing, fermenting and baking. Bread crust and crumb contained the highest FPC and BPC, respectively. Antioxidant activities (AOA) followed the trends of their respective phenolic contents. HPLC analysis demonstrated that different phenolic acids showed various responses to the bread-making process. Total anthocyanin content (TAC) was significantly (p<0.05) reduced through mixing and baking, but fermentation elevated the levels. Anthocyanin extract of purple wheat exerted higher AOA than those of common wheat. Digested purple wheat extracts after in-vitro digestion demonstrated significantly (p<0.05) higher AOA than common wheat. During in-vitro testing, extracts exhibited concentration-dependent effects, while the use of different cell lines exhibited varying levels of cellular antioxidant and pro-oxidant properties. Purple wheat demonstrated higher cytoprotectivity and cellular AOA than those of common wheat. Our findings suggest that purple wheat has the potential to act as functional food in bakery products.
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Proanthocyanidins, anthocyanins and phenolic acids in food barleys of diverse originHambira, Chipo 11 January 2010 (has links)
Phytochemicals found in grains complement those found in fruits and vegetables. These phytochemicals, though minor compounds, contribute to the antioxidant properties which are related to the health benefits associated with the consumption of whole grain. In this thesis project, nine barley genotypes of diverse origin namely CI2230 from Nepal, CI1248 from Israel, 3 Peruvian genotypes; Peru 3, Peru 16 and Peru 35, Hokuto Hadaka from Japan, EX116; a cross between Moroccan and Canadian genotype, EX83; a cross between two Canadian genotypes and EX127; a cross between Canadian and German genotypes were studied. The genotypes were categorized based on appearance into purple, black and yellow grains. Phenolic acids and flavonoids were identified and quantified in these diverse genotypes using HPLC-ESI-MS analysis. The main classes of dietary flavonoids studied in the barleys were anthocyanins and flavan-3-ols. Phenolic acids were identified and quantified (p-coumaric, ferulic, sinapic, caffeic, vanillic). Three ferulic acid dehydrodimers (8-0-4â DFA, 8-5â benzofuran form and 5-5â DFA) were also identified. The most abundant dimeric flavan-3-ols were procyanidins B3 and prodelphinidin B3. The monomeric unit, (+)-catechin, was the most abundant while catechin glucoside (m/z 451) was also identified. Among the Peruvian genotypes, Peru 16 and Peru 35 exhibited relatively high levels of total PA content. Total phenolic content and antioxidant activities of methanolic, acetone and alkali hydrolyzed extracts of the nine barley genotypes was determined by the Folin- Ciocalteau assay, DPPH radical scavenging assay and oxygen radical absorbance capacity (ORAC assay).The acetone extract exhibited the highest antioxidant capacity using all the methods of analysis. Furthermore, dark colored grains were found to exhibit higher contents of phenolic compounds. The phenolic acids, PAs and anthocyanins identified and quantified had significant contribution to the overall antioxidant capacity of the barley whole grain. Four hull-less genotypes namely CI2230, EX127, CI1248 and Peru 35 were further partially sprouted to establish the effects of sprouting on phenolic acid composition. Partial sprouting was observed to significantly increase the soluble conjugated phenolic acids. The barley genotypes studied were found to contain different quantities of phytochemicals and had high proanthocyanidin content thereby rendering them as alternative sources of antioxidants. Barley sprouts present a possible novel food ingredient with improved properties such as phenolic acid composition and other benefits such as easier incorporation into food products under development.
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Health aspects of wine antioxidants: Composition and in vitro bioavailabilityIrine Ginjom Unknown Date (has links)
The antioxidant capacity of phenolic compounds in red wine is suggested to be responsible for their health-promoting effects. Compared to other wines, little information is available on phenolic compositions and antioxidant capacity of Australian wine. Information related to the fate of these phenolics in the body once consumed is also very limited. The overall aim of this research was to investigate the relevance of red wine consumption as a source of health-giving antioxidants in humans. The phenolic composition of wine was determined using the Folin-Ciocalteu (total phenolic), aluminium chloride (total flavonols), methyl cellulose precipitation (MCP) (total tannins), pH differential (total monomeric anthocyanins), bisulfite bleaching (total polymeric anthocyanin fractions), and liquid chromatographic (LC-MS) (individual phenolics) methods. Antioxidant activities were measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2’-azino-bis-93-ethylbenzthiazoline-6-sulfonic acid (ABTS) and oxygen radical absorbance capacity (ORAC) assays. The phenolic and antioxidant data were then used to establish the relationship between these two parameters in wines from different varieties (Shiraz, Cabernet Sauvignon and Merlot) and winemaking stages (crushing, fermentations, oaking and bottling). By using an in vitro digestion model that mimics the upper gastrointestinal tract (GIT) digestion, the stability of the wine phenolics during digestion was examined. Finally, to gain a better understanding of the post-digestion absorption of wine phenolics, their permeability across Caco-2 cell monolayers was evaluated. A total of 8 monomeric anthocyanins and 17 other phenolic compounds were positively identified in the red wines using LC-MS analysis. Most of the phenolic categories showed some positive correlations with the antioxidant activities but none of the individual phenolic compounds showed a strong correlation with the total antioxidant activity of the wine, implying a combined contribution of many wine phenolics to antioxidant effects. The phenolic compositions and antioxidant activities of three of Australia’s most common red wines varieties - Shiraz, Cabernet Sauvignon and Merlot were not different from each other, possibly due to the variability within each grape cultivar. During the winemaking process, the total phenolic content and the associated antioxidant activity of the wine increased during the fermentation process, as more phenolics are being extracted from grape skin, seeds and stems into the wine. During oak and bottle ageing, the total phenolic contents were stabilised. Most of the wine phenolics were more stable under acidic conditions (pH 2 and 5.5) than neutral or alkaline conditions (pH 7.4 and 9). This may partly explain the stability of the wine phenolics subjected to the acidic (pH 2) gastric digestion and their loss following simulated pancreatic digestion (pH 7.4). In addition, sample pre-treatment procedures prior to LC-MS analysis may have removed some antioxidants in the form of degradation products and/or new polymeric compounds following the in vitro gastric and pancreatic digestion processes. The missing products appeared to be detected by both the Folin-Ciocalteu method and ORAC assay, which measured the phenolic compounds and their antioxidant activity, after the pancreatic digestion. This suggests that the instability of phenolic compounds at pH 7.4, results in the transformation of most of the oral phenolic antioxidants into more stable forms in the GIT, which in turn contribute positively to the overall antioxidant activities of the ingested wine. All of the original wine phenolics had very low permeabilities across Caco-2 cell monolayers, except for syringic acid, p-coumaric acid and an unknown phenolic acid. Limited surface area for absorption (0.33 cm2) and the limited peak detection sensitivity in the LC method may have contributed towards the difficulty in detecting and identifying compounds with low permeability. In addition, extensive metabolism of absorbed phenolics by the Caco-2 cells may occur based on the appearance of several new peaks. However, due to their low concentrations and lack of reference, the identities of the new products and metabolites remain unknown. The present in vitro study suggests that upon ingestion, most of the original phenolic compounds in red wine are lost either through degradation to new compounds and/or complexation with other compounds. However, these products seem to possess some antioxidant activity and may be the key compounds responsible for the health-promoting effects of red wine. The limitation of the present study in detecting and fully identifying these breakdown products and metabolites should be addressed in future studies.
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Determination of polyphenol oxidase (PPO) activity, anthocyanin contents and the phytonutrient changes in blueberry juice as influenced by different processing methodsStojanovic, Jelena, January 2008 (has links)
Thesis (Ph.D)--Mississippi State University. Department of Food Science, Nutrition and Health Promotion. / Title from title screen. Includes bibliographical references.
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Microencapsulamento de compostos bioativos da uva (Vitis labrusca L.) e efeito do tratamento pós-colheita com UV-C em uvas BordôKuck, Luiza Siede January 2016 (has links)
O Rio Grande do Sul é o maior produtor de uvas do Brasil, e as cultivares de Vitis labrusca representam mais de 90% da produção, dentre as quais se destacam as variedades Isabel e Bordô, que se caracterizam por conter altas concentrações de polifenóis, principalmente antocianinas, que exibem propriedades antioxidantes e que podem ser usados como corantes em alimentos. Entretanto, a utilização destes compostos em alimentos se torna difícil devido à sua alta instabilidade, e uma das formas de proteger estes compostos das condições adversas do meio é a microencapsulação. O bagaço da uva, proveniente da fabricação de sucos e vinhos, contém uma elevada concentração de polifenóis, e é composto em grande parte pela casca da uva. Dessa forma, este trabalho de Tese, teve como primeiro objetivo a extração dos polifenóis da casca das uvas Isabel e Bordô, e seu microencapsulamento utilizando diferentes materiais de parede, o qual foi dividido em três etapas. Na primeira etapa, foi realizada a separação dos compostos fenólicos mediante extração aquosa em meio ácido da casca de uva Isabel. A seguir, o extrato foi submetido à atomização para obtenção das micropartículas, utilizando goma arábica, β-ciclodextrina e hidroxipropil-β-ciclodextrina como agentes encapsulantes, combinadas em concentrações máximas de 5%. Os pós obtidos foram avaliados quanto aos fenóis totais, antocianinas monoméricas totais, flavonoides, flavanols, atividade antioxidante (DPPH, CUPRAC e HRSA), cor, umidade, atividade de água, solubilidade, higroscopicidade, temperatura de transição vítrea e microestrutura. De forma geral, os pós obtidos apresentaram alta higroscopicidade e baixa temperatura de transição vítrea, além de aglomeração das partículas. O tratamento elaborado com 3% de goma arábica e 2% de β-ciclodextrina foi considerado o melhor, com maior retenção de flavonoides (67,2%), flavanols (51,1%), atividade antioxidante por DDPH (55%) e CUPRAC (58,8%), menor higroscopicidade (17,33%) e maior temperatura de transição vítrea (32,85 °C). Na segunda etapa, o extrato fenólico aquoso acidificado da casca de uva Bordô foi atomizado e liofilizado para a obtenção das micropartículas, utilizando goma arábica, goma guar parcialmente hidrolisada e polidextrose, em um total de 10% de material de parede. Os pós obtidos foram avaliados quanto ao conteúdo de fenóis totais, antocianinas monoméricas totais, atividade antioxidante (DPPH, CUPRAC, HRSA), cor, umidade, atividade de água, solubilidade, higroscopicidade, temperatura de transição vítrea, tamanho de partícula e microestrutura. Foram obtidas altas retenções, maiores que 80% para fenóis totais e antocianinas monoméricas totais, e entre 45 e 84% para atividade antioxidante em todos os tratamentos estudados. Os pós atomizados tiveram menor umidade, atividade de água e tamanho de partícula, maior solubilidade e temperatura de transição vítrea, além de melhores características morfológicas do que os pós liofilizados. O pó obtido por atomização com 5% de goma guar parcialmente hidrolisada e 5% de polidextrose foi considerado o melhor tratamento, visto que teve maior retenção de fenóis totais (89,0%), antocianinas monoméricas totais (99,5%) e atividade antioxidante por DPPH (57,3%) e CUPRAC (83,2%). Na terceira etapa, dispersões de extrato de casca de uva Bordô com 5% de goma guar parcialmente hidrolisada e 5% de polidextrose, que foi considerado o melhor tratamento dentre todos os elaborados com uva Isabel e Bordô, foram atomizadas e liofilizadas para obtenção das micropartículas, que foram submetidas a testes acelerados de armazenamento (umidades relativas de 75 e 90% em temperaturas de 35, 45 e 55 °C) e de simulação de digestão gastrointestinal (divididos em duas fases: fase gástrica e fase intestinal). Foram avaliados os conteúdos de fenóis totais, antocianinas monoméricas totais e atividade antioxidante por ABTS. Quanto às provas aceleradas, a temperatura teve um efeito significativo na diminuição no conteúdo de fenóis, com retenções de 82,5% a 93,5%. Na redução do conteúdo de antocianinas monoméricas totais foi significativo o efeito da temperatura, umidade relativa e tempo, com retenções de 3,9 a 42,3%. A redução do teor de antocianinas monoméricas totais exibiu cinética de primeira ordem, e os valores de z e Ea indicaram que o pó liofilizado é mais instável às mudanças de temperatura, quando utilizadas temperaturas mais elevadas. Por outro lado, os valores de D e t1/2 foram muito próximos entre os dois pós, o que indica pouca diferença de estabilidade entre eles nas temperaturas utilizadas neste estudo. Os parâmetros termodinâmicos indicaram que a reação foi endotérmica e não espontânea. A atividade antioxidante teve comportamento similar ao dos fenóis totais, com retenção final de 38,5 a 59,5%. Quanto à simulação da digestão gastrointestinal os dois pós tiveram liberação de fenóis de aproximadamente 80% na fase gástrica, e aumento significativo da liberação na fase intestinal, onde, na última hora de experimento, o pó atomizado teve 90,6% de liberação e o liofilizado 94,9%. Comportamento similar foi observado para a atividade antioxidante, onde o pó atomizado e o pó liofilizado tiveram percentuais próximos a 50% na fase gástrica e aumento significativo na fase intestinal, onde na última hora do experimento o pó atomizado teve 69,4% da atividade antioxidante e o pó liofilizado 67,8%. Entretanto, as antocianinas monoméricas tiveram redução significativa de aproximadamente 50% do seu conteúdo na fase intestinal, onde, na última hora de experimento, o pó atomizado teve 39% de liberação e o liofilizado 39,8%. O método de obtenção das micropartículas não influenciou na estabilidade dos pós, tanto nos testes acelerados de armazenamento quanto na simulação da digestão gastrointestinal. Como segundo objetivo foi avaliado o efeito da irradiação UV-C em uvas Bordô, como tratamento pós-colheita. Foram estudadas duas safras de anos diferentes, sendo que na primeira as uvas foram submetidas a 0, 0,5, 1, 4, 10 e 30 minutos de irradiação (120 W) e armazenadas a 22 °C, enquanto que na segunda safra as uvas foram submetidas à irradiações com UV-C (120 W) por 0, 0,5 e 4 minutos, combinada com ultrassom (40 kHz) por 5 minutos e armazenadas a 22 °C. Na primeira safra, as uvas não apresentaram aumento dos compostos bioativos e da atividade antioxidante. Entretanto, na segunda safra, os resultados indicaram o aumento significativo no conteúdo de fenóis totais, antocianinas monoméricas totais e na atividade antioxidante para as uvas irradiadas por 0,5 minutos com UV-C e para as irradiadas com UV-C por 4 minutos em combinação com ultrassom por 5 minutos, com aumentos de 1,2 a 2,0 vezes em relação ao controle, não havendo mudanças significativas na cor das uvas irradiadas. / The state of Rio Grande do Sul, Brazil, is the greatest producer of grapes in the country. Vitis labrusca cultivars constitute more than 90% of production, underscoring Isabel and Bordô varieties, featuring high concentrations of polyphenols, especially antioxidant anthocyanins used as food coloring. Since the use of the compounds in food is rather difficult due to their unstableness, microencapsulation is one of the methods to protect the compounds from adverse environmental condition. Grape pomace, the residue from the manufacture of juice and wine, has high polyphenol concentration and is mainly formed by grape skin. Current thesis aims at extracting polyphenols from the skin of Isabel and Bordô grape varieties and their micro-encapsulation by different wall materials. Research was divided into three stages. The first stage comprised the separation of phenolic compounds by water extraction in the acid medium of the skin of the Isabel grape variety. The extract was spray-dried for microparticles by means of gum arabic, β-cyclodextrin and hydroxypropyl-β-cyclodextrin as encapsulating agents at maximum 5% concentrations. Powders were assessed for total phenols, total monomer anthocyanins, flavonoids, flavanols, antioxidant activity (DPPH, CUPRAC and HRSA), color, humidity, water activity, solubility, hygroscopicity, glass transition temperature and micro-structure. As a rule, the powders featured high hygroscopicity, low glass transition temperature and particle agglomeration. Treatment with 3% of gum arabic 3% and 2% of β-cyclodextrin was the best, with the highest retention rate of flavonoids (67.2%), flavanols (51.1%), antioxidant activity, and with DDPH (55%) and CUPRAC (58.8%), lowest hygroscopicity (17.33%) and highest glass transition temperature (32.85 °C). In the second stage the acidified water phenolic extract from the Bordô grape skin was spray-dried and freeze-dried for microparticles with gum arabic, partially hydrolyzed guar gum and polydextrose, with a total 10% of wall material. Powders were assessed for total phenols, total monomer anthocyanins, antioxidant activity (DPPH, CUPRAC, HRSA), color, humidity, water activity, solubility, hygroscopicity, glass transition temperature, particle size and micro-structure. High retentions occurred, with more than 80% for total phenols and total monomer anthocyanins; and between 45 and 84% for antioxidant activity in all treatments under analysis. Atomized powders had lower humidity, water activity and particle size, greater solubility, higher glass transition temperature, and better morphological characteristics than the freeze-dried powders. The powder obtain by spray-dried with 5% of partially hydrolyzed guar gum and 5% of polydextrose was the best treatment due to greater retention of total phenols (89.0%), total monomer anthocyanins (99,5%) and antioxidant activity for DPPH (57.3%) and CUPRAC (83.2%). The third stage comprised dispersions of the extract of the Bordô grape skin with partially hydrolyzed guar gum 5% and polydextrose 5%, or rather, the best treatment among those prepared with Isabel and Bordô grapes. Dispersions were spray-dried and freeze-dried to obtain microparticles which underwent fast storage tests (relative humidity rates 75 and 90% at 35, 45 and 55 °C) and gastrointestinal digestion simulations (divided into two phases: gastric and intestinal phases). Total phenols, total monomer anthocyanins and antioxidant activity for ABTS were evaluated. Fast tests revealed that temperature had a significant effect on the decrease in phenol contents, with 82.5 - 93.5% retentions. Temperature, relative humidity and time were significant on the reduction of total monomer anthocyanin contents, with 3.9 – 42.3% retentions. Decrease in total monomer anthocyanin rates revealed a first order kinetics, whilst z and Ea rates indicated highly unstable freeze-dried powder for changes in temperature when higher temperatures are employed. On the other hand, D and t1/2 rates were very close between the two powders, revealing slight stability difference between the two at temperatures employed in current study. Thermodynamic parameters demonstrated an endothermic and non-spontaneous reaction. Antioxidant activity behaved similarly to total phenols with a final retention between 38.5 and 59.5%. In the case of gastrointestinal digestion simulation, the two powders released 80% phenols during the gastric phase and a significant increase in release during the intestinal phase in which spray-dried and freeze-dried powders had 90.6% and 94.9% release during the last hour of the experiment. A similar behavior was detected for antioxidant activity in which spray-dried and freeze-dried powders featured 50% during the gastric phase and a significant increase during the intestinal one, with 69.4% and 67.8% of antioxidant activity respectively by the spray-dried and freeze-dried powders during the last hour of the experiment. However, monomer anthocyanins had a significant 50% reduction of contents in the intestinal phase in which the spray-dried and freeze-dried powders had 39% and 39.8% release respectively during the last hour of the experiment. The methods for obtaining microparticles failed to affect the stability of the powder in fast storage tests and in gastrointestinal simulation tests. Current research also evaluated the effect of UV-C irradiation on Bordô grapes for post-harvest treatment. Two harvests in two different years were analyzed: grapes of the first harvest underwent 0, 0.5, 1, 4, 10 and 30 minutes irradiation (120 W) and stored at 22 °C, whereas grapes of the second harvest underwent UV-C irradiations (120 W) during 0, 0.5 and 4 minutes, coupled to ultrasound (40 kHz) for 5 minutes and stored at 22 °C. The former did not have any increase in bioactive compounds and antioxidant activity. Results of the latter, however, demonstrated a significant increase in total phenols, total monomer anthocyanins and antioxidant activity for grapes irradiated during 0.5 minutes with UV-C and for those irradiated with UV-C for 4 minutes plus ultrasound for 5 minutes. There was 1.2 - 2.0 times increase when compared to control, with no change in color in the irradiated grapes.
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