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  • 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.
1

The Effects of Agricultural Waste-Based Compost Amendments in Organic Pest Management

Stephenson, Gregg T 01 June 2019 (has links) (PDF)
Soil-borne pests and pathogens, such as Verticillium dahliae, can devastate a wide range of annual and perennial crops. Current management options for organic production are limited and sustainable management of pathogens, weeds, and arthropods is important for staying profitable and reducing the use of harmful chemicals. Organic soil amendments play an important role in supplying some of the nutritional needs of vegetable crops and improving soil structure, while also contributing to pest control. The objective of this research was to determine the effects of grape and olive-based composts on soil pathogen load, arthropod communities, and weed biomass and diversity. Field experiments were conducted in both organic and conventionally grown bell pepper (Capsicum annuum L.) systems during the summer growing season of 2018 on the Cal Poly campus in San Luis Obispo, California. Four different organic amendment treatments were tested including: olive based compost, grape based compost, dairy manure compost, and plant waste compost. Abundance of the fungal pathogen Verticillium dahliae was assessed from composite soil samples collected at several time points throughout the growing season. Olive, grape, and plant waste composts all displayed significant reduction of V. dahliae abundance between two to eight weeks post application of treatment when compared to the control. Insufficient evidence was found correlating farm management type with V. dahliae abundance after adjusting for treatment and time. Total dry weed biomass was assessed after one month of unhindered growth. The organic amendments tested appeared to alter weed species composition but not overall biomass though no significant differences were found. The soil arthropods symphylans and collembolans were sampled throughout the growing season, significant trends in population were found over time but not across treatments. This research demonstrates how agricultural waste-based compost amendments have potential as tools in pest management.
2

Effect of Storage Period and Treatment on the Composition and Digestibility of Olive Pomace in Cattle

Ulloa, Alexis Cecilia 01 September 2018 (has links)
Utilizing local by-products can serve to significantly reduce the current feed costs for ruminant producers. The objective of this study is (1) to evaluate the effects of chemical and bacterial inoculants in combination with ensiling, on the nutritional value and ensiling compatibility of olive pomace (OP) and (2) to identify the most biologically favorable treatment and ensiling day of OP for feeding to cattle. Freshly centrifuged OP (Olivas de Oro Olive Company, Creston, CA) was treated with one of four treatments: (1) no additives (control; CONT); (2) urea applied at 5% of DM (UREA; Agrium U.S. Inc, Loveland, CO); (3) SiloSolve MC (SS; a mixture of Enterococcus faecium M74, Lactococcus lactis SR3.54, and Lactobacillus plantarum CH6072 applied at 1.5 x 105 cfu/g of fresh forage; Chr. Hansen A/S, Hørsholm, Denmark); (4) SiloSolve MC applied at the same rate as treatment 3 with calcium oxide (CAO; Flinn Scientific, Batavia, IL) applied at 5% of DM. Treated OP was ensiled in quintuplicates into 20-L laboratory silos with vents, which were sealed for 2, 10, 60, and 120 d in a completely randomized design. At 0 d, DM was 2 and 5% higher for UREA and CAO, respectively, while ash and pH were highest for CAO. Fat tended to be higher for SS and CP was highest for UREA by 60 d (23.8%). CAO had significantly lower fiber portions, ethanol and yeasts (P < 0.05), and higher acetic acid than CONT. No significant differences were observed at 12 and 24 h in situ compared to CONT, yet at 48 h, NDFD was greatest for CONT and SS (P < 0.001). Lactic acid increase with prolonged ensiling with UREA having the highest content at 120 d (0.716 %) and acetic decreased for CONT, SS, and CAO. SS contained the most LAB (8.5 log cfu/ fresh g). Yeasts, molds, and sugars significantly decreased with ensiling. In conclusion, OP was determined to be a viable nutritional source for ruminants given its chemical composition and effective preservation after 120 d of ensiling that could be improved with chemical and bacterial inoculants.
3

Production of bio-plastic materials from apple pomace : A new application for the waste material / Produktion av bio-plast material från äpplerester

Gustafsson, Jesper, Landberg, Mikael January 2018 (has links)
Extensive quantities of apple pomace are generated annually but disposal of this waste is still much disputed. In EU alone, 500 000 tons are produced every year. Without further treatment, the acidic character of apples with their high sugar and low protein content makes the pomace unsuitable for landfilling and animal feedstock. However, further treatment is usually not economically feasible. This study addresses this issue by introducing a new approach for the apple pomace to produce sustainable materials.  The high content of sugars in apple pomace which can be reshaped and reformed at higher temperatures makes the waste material suitable for plastic production. Other components found in apple pomace are 5 % proteins and 1.5 % fats. Fibers are abundant, dietary fibers amounts for more than half (55 %) the original apple pomace weight. Phenols, sorbitol and acids can be found in minor mount, 2 % or less. The apple pomace itself is a mixture of mostly pulp and peel which corresponds to 9/10 of the total mass. Whereas seeds, seed core and stalk are the remaining 1/10. The possibilities of utilizing apple pomace to produce biofilms and 3D shapes have been investigated. The effects of introducing orange pomace, another waste material produced in extensive quantities, to apple pomace samples has also been studied.  Two methods were used to produce bioplastic materials; solution casting and compression molding. Glycerol was used as a plasticizer. Apple pomace, either washed or not washed, was oven-dried and milled into a fine powder. Using compression molding, plates or cups of the two powders with different amounts of glycerol were prepared. Mixtures of apple pomace and orange pomace, with or without glycerol, were prepared in the same way. The apple pomace was also used in a film casting method to produce plastic films. Applying laser cutting to the plates and plastic films, dog-bone specimens were created whose mechanical properties were analysed using a universal testing machine.  Highest values in terms of tensile strength and elongation at max was reached with bioplastics produced from solution casting where the values varied in the range 3.3 – 16 MPa and 11 – 55 % respectively. The compression molding approach resulted in tensile strength values in the range 0.94 – 5.9 MPa whereas the elongation at max was in the range 0.30 – 1.9 %. A possible application for this material could be disposable tableware which does not require high mechanical strength.  It was shown that it is possible to produce 3D structures and plastic films from apple pomace. Washed apple pomace with glycerol has similar properties as not washed apple pomace without the plasticizer. Adding orange pomace to apple pomace samples increases the tensile strength at the expense of the elongation at max. The pressing conditions and powder size greatly effects the mechanical properties, where a larger powder size lower the values for the mechanical properties. This new approach paves the way for a new utilization of apple pomace to replace some petroleum-based materials and at the same time solve the disposal problem of apple pomace.
4

Méthanisation de marc de raisin. Caractérisation et optimisation du procédé et des prétraitements. / Anaerobic digestion of grape pomace. Characterization and optimization of the process and the pretreatments

El Achkar, Jean 30 May 2017 (has links)
La digestion anaérobie représente un élément clé dans la dynamique de développement durable contribuant à la valorisation verte des déchets organiques sous forme de biogaz et d'engrais. Dans le cadre de ce travail de thèse franco-libanais, nous cherchons à valoriser le marc de raisin, déchet majeur et principal sous-produit issu de la viniculture, par la digestion anaérobie, afin de générer de l’énergie dite verte sous forme de méthane. Dans un premier temps, le potentiel méthane du marc de raisin est démontré, validant notre biomasse végétale comme source potentielle d’énergie. Des informations détaillées sur les productions maximales de méthane à partir du marc entier, des pulpes et des pépins, séparément, sont obtenues en mode batch à 37 °C. La faisabilité technique du procédé est alors validée suite à une extrapolation au mode continu. De plus, des essais d’acclimatation du digesteur continu à la température moyenne de la vallée de la Bekaa (25 °C) permettent de simuler et d’adapter le système au milieu libanais. D’autre part, nous avons mené une caractérisation bio-physico-chimique de différents cépages de marcs de raisins en provenance de différentes régions viticoles. La diversité du contenu lignocellulosique et du potentiel méthanogène des substrats choisis a été mise en évidence. Une corrélation négative existe, en particulier, entre le potentiel méthane et les teneurs en lignine et en cellulose. Afin d’intensifier la production de méthane, le dimensionnement des digesteurs anaérobies en mode continu est optimisé en déterminant un optimum de fonctionnement pour une charge appliquée de 3,7 kg DCO m-3 j-1 et un temps de séjour de 20 jours. Enfin, nous évaluons les effets d’une variété de prétraitements (congélation, traitement alcalin, traitement acide, ultrasons et champs électriques pulsés) sur la production de méthane et sur la biodégradabilité des fractions. Le couplage du traitement alcalin à 10% NaOH avec la congélation à -20 °C s’avère être le meilleur procédé d’intensification. / Anaerobic digestion is considered to be a crucial part of a sustainable development strategy, contributing to the green valorization of organic waste as biogas and fertilizers. As part of this doctoral thesis, we explored the valorization of grape pomace, the major waste and main by-product of winemaking, by anaerobic digestion, to generate green energy in the form of methane. Firstly, the methane potential of grape pomace is demonstrated, validating our vegetal biomass as a potential source of energy. Detailed information on the maximum production of methane from whole pomace, pulps and seeds are obtained in batch mode at 37 °C. The technical feasibility of the process is then validated following an extrapolation to the continuous mode. Moreover, the acclimation of the continuous digester at the average temperature of the Beqaa valley (25 °C) allowed to simulate and adapt the current system to the Lebanese environment. On another note, we carried out a bio- physico-chemical characterization of different grape varieties from different wine-growing areas. The diversity of the lignocellulosic content and the methane potential of the selected substrates was highlighted. A negative correlation exists, in particular, between the methane potential and the lignin and cellulose fractions. In order to intensify methane production, we conducted an optimization of anaerobic digesters dimensioning in continuous mode by determining an optimum of operation for an applied load of 3.7 kg COD m-3 d-1 and a residence time of 20 days. Finally, we evaluated the effects of a variety of pretreatments (freezing, alkaline treatment, acid treatment, ultrasounds and pulsed electric fields) on the methane production and the biodegradability of lignocellulosic fractions. The coupling of the alkaline treatment using 10% NaOH with freezing at -20 °C seems to be the best intensification process.
5

Možnosti využití výlisků z bezinek / The possibility of using of elderberry fruit pomace

Ondrušová, Pavlína January 2018 (has links)
This diploma thesis concerns the determination of anthocyanin pigments in the elderberry pomace (Sambucus nigra L). The theoretical part describes in general the plant specification, its chemical composition, botanical characteristics and the possibility of utilization of elderberry in food processing industry and in pharmacy. However, the main concern of this thesis are the anthocyanins. This part is closely focused on chemical structure and factors that have significant influence over their stability. There are briefly summarized the positive effects of these colourants and their use in the food industry. In the experimental part, the elderberry juice and the extracts from the rhizomes were prepared. Two different solvents, a 1: 1 water / ethanol mixture and a mixture of water and methanol in the same ratio were used as extractors. To identify and quantify the dyes in the prepared samples, a chromatographic separation system (HPLC) with a Kinetex EVO C18 column and isocratic elution of the combined mobile phases of water of acetonitrile and formic acid was developed. The analysis only took 12 minutes. Two major dyes cyanidin-3-glucoside and cyanidin-3-sambubioside were identified and quantified by HPLC. The largest amount of anthocyanins was obtained by extracting mixture methanol / water (594.6 ± 0.42 mg.100 g-1). The content of anthocyanin dyes in dry extracts and juice was also determined by the often-used pH-differential method. Both results were compared. The HPLC method provided very accurate results against the less demanding pH-differential assay method, which proved to be suitable for the indicative measurement of anthocyanin content in real samples.
6

The Effects of Cofermentation of Cider and Apple Pomace on Cider Attributes

Affonso, Abigail D 01 June 2022 (has links) (PDF)
Phenolics are critical to the sensory attributes and health benefits of hard cider due to their contribution to the flavor, mouthfeel, and antioxidant activity. With the increase in demand for cider, the use of dessert apple varieties has become more common leaving ciders lacking in phenolics. However, a promising method to increase their phenolic content is through maceration with apple pomace. This study evaluated the effect maceration with apple pomace during cider fermentation on the extraction of phenolic compounds, as well as its effect on the sensory properties of the final product. For this study, ciders were fermented with 0% (control), 20%, 35%, and 50% of the average pomace created during production of the apple must. After fermentation, the ciders were analyzed for acid content, total phenolic content (TPC), alcohol by volume (ABV), color, volatile profile, and sensory properties. The ciders fermented with apple pomace went through malolactic fermentation. During the maceration phenolics were extracted which resulted in an increase in phenolic content in cider. Compared to the control, the treatment ciders were also seen to have higher ABV and TPC, lower acidity, and a different aromatic profile: decreased acetaldehyde and increased ethyl acetate, isoamyl alcohol, and phenylethyl alcohol. The color measurements suggests that treatment ciders were lighter, with a higher red and yellow color compared to the control cider. The sensory analysis revealed the treatment ciders were perceived as less acidic and astringent, but more bitter than the controls. This study shows the addition of apple pomace in its native state increases total phenolic content and could be favorable to produce well rounded ciders. This study shows maceration is a promising technique for increasing phenolic content in ciders.
7

Physical Treatments To Modify The Functionality Of Carrot Pomace And The Development Of An Enhanced Beef Patty

Richards, Jordan O.A 01 September 2023 (has links) (PDF)
Approximately one-third of the global food produced for human consumption is lost or wasted somewhere along the food chain. Carrots are one of the most important and widely produced root vegetables grown worldwide; they are rich in many beneficial bioactive compounds such as dietary fiber and carotenoids. Every year, an estimated 29% of processed carrots are lost as waste. The U.S. is the 3rd largest producer of carrots worldwide, 85% of which come from California. During carrot juice processing, up to 50% of the raw material remains as carrot pomace. Carrot pomace may contain up to 55% total dietary fiber, which is thought to have important functional properties such as water holding and fat binding. The objectives of this project were to: 1) Investigate how physical pretreatment and drying treatment affect the functional and chemical properties of carrot pomace, 2) evaluate the impact that carrot pomace as a functional ingredient will have on the physical and chemical properties of beef patties, and 3) validate the developed beef patties using a consumer sensory test to ensure that the products have acceptable sensory attributes. High shearing and hydraulic pressing pretreatments (HSHP) increased the swelling capacity of freeze-dried carrot pomace by 59% and dehydrated carrot pomace by 34%. Freeze-dried carrot pomace also retained 33% more carotenoids compared to dehydrated pomace. The drying method significantly impacted the functional properties of carrot pomace. Freeze drying improved the water holding capacity by 22% and fat binding capacity by 194% over dehydrated carrot pomace. The addition of dried carrot pomace increased the cooking yield and water-holding capacity of beef patties by 5-15% and 12%, respectively, without significantly changing their textural properties or chemical composition. Eighty-six (86) consumers took part in sensory testing to evaluate beef patties formulated with carrot pomace. Overall, there were no significant differences in liking scores between the carrot pomace patties at 1% & 3% and the control patty. Scores were not changed significantly when patties were consumed with a bun. These results suggested that carrot pomaces may be physically modified to be utilized as a functional ingredient in the food industry.
8

Iskorišćenje tropa borovnice i maline u formulaciji bezglutenskog keksa sa dodatom vrednošću / Valorisation of blueberry and raspberry pomace through the formulation of value-added gluten-free cookie

Šarić Bojana 29 October 2016 (has links)
<p>Sporedni proizvodi industrijske prerade voća, trop borovnice i maline, postupcima su&scaron;enja i mlevenja prevedeni su u oblik pogodan za aplikaciju u prehrambene proizvode. Ovako dobijeni sastojci imaju visok sadržaj prehrambenih vlakana, esencijalnih masnih kiselina poput linolne i &alpha;-linolenske, a karakteri&scaron;e ih i izbalansiran odnos PUFA/SFA. Od makronutrijenata, u najvećoj koncentraciji prisutni su K, Mg i Ca. Imajući u vidu da su glavne fitohemikalije bobičastog voća polifenolna jediinjenja, u proizvedenim funkcionalnim sastojcima određen je sadržaj ukupnih rastvorljivih polifenola, antocijana i flavonoida, kao i sastav i sadržaj odabranih polifenolnih jedinjenja primenom LC/MS-MS tehnike.<br />Primena osu&scaron;enih i samlevenih tropova kao sastojaka prehrambenih proizvoda ispitana je u formulaciji bezglutenskog keksa, sa ciljem njegovog funkcionalnog obogaćivanja. Za optimizaciju formulacije keksa kori&scaron;ćen je postupak odzivne povr&scaron;ine (RSM), a formulacija u kojoj je bezglutenska sme&scaron;a zamenjena sa 28,2% tropa borovnice i 1,8% tropa maline dobijena je kao optimalna, uzimajući u obzir sve zadate kriterijume. Dodatkom ova dva funkcionalana sastojka u gorenavedenom odnosu, postignuto je značajno pobolj&scaron;anje nutritivnih svojstava bezglutenskog keksa, a dobijeni proizvod po kvalitetu može da parira komercijalno dostupnim funkcionalno obogaćenim keksovima, namenjenim zdravoj populaciji.<br />Rezultati dijetetske interventne studije sprovedene na 20 zdravih, normalno uhranjenih ispitanika ženskog pola, ukazuju da se konzumiranjem kreiranog bezglutenskog keksa u količini od 32 g dnevno, postiže značajna redukcije LDL holesterola, i povećanje nivoa adiponektina u krvi, a budući da se ovaj adipocitni-sekretorni protein dovodi u vezu sa antiinflamatornim i antiaterogenim potencijalom u tretmanu metaboličkog sindroma i dijabetesa tipa 2, može se očekivati protektivno dejstvo kreiranog bezgutenskog keksa.</p> / <p>Blueberry and raspberry pomace, by-products from fruit juice industry, were processed into the new food ingredients by drying and grinding. The obtained functional ingredients are characterized by high content of dietary fibres and essential fatty acids (linoleic and &alpha;-linolenic acid), as well as by optimal ratio of PUFA/SFA. The main macronutrients in dried and ground pomace are K, Mg and Ca. The content of total phenolic compounds, anthocyanins and flavonoids were determined, as well as composition and content of individual phenolic compounds using LC/MS-MS in order to evaluate their antioxidant potential.<br />In the form of dried powder, blueberry and raspberry pomace were used as ingredients in formulation of gluten-free cookies. Response surface methodology (RSM) approach was applied to obtain optimal ingredients proportion. Formulation in which gluten-free flour mixture is substituted with 28.2% of the blueberry and 1.8% of the raspberry pomace was found to be optimal following the used optimization criteria. Addition of blueberry and raspberry pomace has led to a remarkable improvement in nutritional properties, and resulted in a product with similar nutritional profile with commercially available gluten containing cookies.<br />Dietary intervention study on a group of 20 healthy, normal weight female subjects was conducted to investigate the health effect of the created gluten-free cookies. The results showed a significant reduction in levels of LDL cholesterol, and an increase in plasma concentrations of adiponectin, suggesting a potential positive effect of the created product on human health.</p>
9

Application of Apple pomace for Fungal Cultivation / Användning av Äpplepressmassa för svampodling

Floberg Karlsson, Bill, Viitala, Jonatan January 2019 (has links)
Apple pomace is a solid by-product acquired from pressing and crushing millions of tons of apple in juice-industries. It represents 25-30 % of the original fruit and consists of peels, seeds and pulp. This raw material has multiple applications due to its high carbohydrate and moisture content. This bachelor thesis evaluated the use apple pomace acquired from Herrljunga cider for the cultivation of a filamentous fungus to produce biomass and ethanol. Different pretreatment strategies were applied to the apple pomace to extract as much sugars as possible. Several batches were made by mixing pomace and distilled water at different ratios (g pomace per g water) and different water temperatures. Apple juice was produced by filtering soaked pomace using a fine fabric. Apple pomace suspensions were made by adding pomace and water without mixing it (non-homogenised) and homogenised suspensions by mixing with a kitchen blender. Some apple juice batches were pH adjusted to 5.5 to investigate the effect on the fungal growth. The batches were put in Erlenmeyer flasks, sterilised and inoculated with the fungal strain Rhizomucor that has been isolated from Indonesian leaves used for tempe preparation. The Erlenmeyer flasks were incubated in a water shake for 72 h. Samples were taken every 24 h to follow sugar and ethanol concentrations. The samples were analysed by HPLC (High-Performance Liquid Chromatography). The results showed that apple pomace suspension did not perform well compared to the apple juice since the suspension was too viscous and lacked oxygen for the fungus to grow properly in the solution. The apple juice did show a significant improvement compared to the suspension, however pH adjustment to 5.5 had a negative impact on the fungal growth. Cold pre-treatment with an apple pomace to water ratio of 1 g pomace /g water produced the most biomass, with a yield of 9.7 g biomass per kg dry apple pomace. For ethanol production, an apple pomace to water ratio of 1 g pomace /g water using hot water had the highest yield of 11.2 g ethanol per kg dry apple pomace. / Äppelpressmassa är en solid biprodukt, producerad genom att pressa och trycka milliontals ton äpple i bland annat juiceindustrier. Den kvarstående massan motsvarar 25-30 % av äpplet och består utav skal, frön och fruktkött. Denna råvara har många tillämpningar då den har ett högt kolhydrat- och vätskeinnehåll. Detta examensarbete utvärderade användningen av äppelpressmassa från Herrljunga cider för att odla en filamentös svamp i syfte att producera biomassa och etanol. Massan blev utsatt för olika förbehandlingar för att extrahera så mycket socker som möjligt. Olika satser gjordes genom att blanda äppelpressmassa med vatten i olika förhållanden (g äppelpressmassa per g vatten) och olika vattentemperaturer. Äppeljuice producerades genom att filtrera blöt massa med ett fint tyg. Suspensioner gjordes genom att tillsätta vatten till massan och inte blanda det (icke-homogent). En annan variant gjordes genom att blanda äppelpressmassa och vatten med en mixer (homogent). Några utav äppeljuicesatserna pH justerades till 5.5 för att se hur det påverkade svamptillväxten. Satserna flyttades till Erlenmeyer flaskor, steriliserades och ympades med den filamentösa svampen Rhizomucor. Erlenmeyer flaskorna flyttades till ett skakvattenbad för att jäsa i 72 timmar. Prover togs var 24:e timma för att se socker- och etanolkoncentrationerna ändras. Detta analyserades med hjälp utav en HPLC. Resultaten visade att suspensionssatserna inte presterade bra jämfört med äppeljuicesatserna. Detta misstänks bero på att innehållet var väldigt visköst och hade lågt syreinnehåll för svampen att kunna växa. Att justera pH till 5.5 för äppeljuicesatserna visade sig inte vara bra, de presterade sämre jämfört med justerade satser. Förbehandlingen med en äppelpressmassa till vatten förhållandet på 1 g äppelpressmassa/1 g kallt vatten producerade mest biomassa med ett utbyte av 9.7 g torr biomassa per kg torr äppelpressmassa. För etanolproduktion hade förbehandlingsmetoden med en äppelpressmassa till vatten förhållandet på 1 g äppelpressmassa/1 g varmt vatten högst utbyte med 11.2 g etanol per kg torr äppelpressmassa.
10

Caracterização e estabilidade de micropartículas de antocianinas extraídas do bagaço da produção do suco de jabuticaba

Souza, Ana Cardinale Pereira January 2014 (has links)
A busca de fontes alternativas de pigmentos naturais tem estimulado o desenvolvimento de pesquisas com diferentes frutos e resíduos tropicais. No presente trabalho, optou-se por estudar o aproveitamento do bagaço gerado na produção de suco de jabuticaba. A jabuticaba é uma fruta rica em antocianinas, um pigmento natural que, além da capacidade de conferir cor, também possui atividades benéficas à saúde. No entanto, o seu uso como corante natural na indústria de alimentos como uma forma de substituir os corantes sintéticos é limitado pela sua instabilidade frente às condições de processamento e da presença de outros componentes. Uma alternativa para aumentar a estabilidade das antocianinas é através da técnica de microencapsulação no qual o ingrediente sensível é protegido dentro do material de revestimento. Assim, o presente estudo objetivou a produção, caracterização e a verificação da estabilidade dos pós obtidos por liofilização utilizando a maltodextrina, a pectina e a proteína isolada de soja como materiais de parede em diferentes proporções. Os pós foram caracterizados quanto ao teor de umidade, atividade de água, solubilidade, higroscopicidade, tamanho de partícula, morfologia, análise térmica e colorimétrica, teor de fenólicos totais, antocianinas monoméricas e atividade antioxidante com o radical ABTS. Os mesmos também foram avaliados quanto à estabilidade na presença da luz UV durante a estocagem e comparadas com o extrato de antocianinas liofilizado não microencapsulado. As antocianinas presentes no bagaço de jabuticaba foram extraídas com ultrassom utilizando a água acidificada com ácido cítrico (1 %) O extrato de antocianinas concentrado apresentou uma quantidade de antocianinas monoméricas de 510 ± 0,09 mg.100 g-1 de bagaço, um teor de fenólicos totais de 12.860 ± 1,5 mg AGE.100 g-1 bagaço e uma atividade antioxidante de 39.590 ± 1,25 μM TE.g-1 de bagaço todos expressos em base seca. Os pós produzidos por liofilização apresentaram estruturas irregulares amorfas sem estrutura cristalina com tamanho médio de partículas entre 311,66 – 419,74 μm com distribuição bimodal. Além disso, as amostras apresentaram baixos valores de umidade (2,09 ± 0,10 a 4,15 ± 0,32%), atividade de água (0,053 ± 0,003 a 0,162 ± 0,002), higroscopicidade (10,8 ± 0,1 a 14,2 ± 0,3 g/100g) e baixa solubilidade em água (10,9 ± 0,1 a 21,3 ± 0,2 %), atributos desejáveis na obtenção de alimentos em pó. Com a análise térmica foi possível verificar que houve a microencapsulação das antocianinas com os diferentes materiais de revestimento testados devido à formação de novas transições endotérmicas, e ainda foi possível observar que os pós apresentaram uma estabilidade térmica até a temperatura de 130 °C. A fotoestabilidade dos pós liofilizados bem como do extrato de antocianinas liofilizado não microencapsulado armazenados por 90 dias mostraram que a degradação desse pigmento seguiu uma cinética de primeira ordem e os parâmetros cinéticos foram calculados Para o extrato não microencapsulado os valores obtidos para a constante de degradação e tempo de meia-vida foram iguais a 0,0135 d-1 e 51 dias, respectivamente, correspondendo a uma redução de 77% de antocianinas monoméricas, 56 % de fenólicos totais e 43 % da capacidade antioxidante. Por outro lado, os materiais de parede protegeram o pigmento do efeito deletério da luz em mais de 90 % em relação ao teor de fenólicos totais, 80 % para a quantidade de antocianinas monoméricas, de modo que a atividade antioxidante foi mantida em 70 % durante o período de estocagem. Os valores da constante de degradação para todas as formulações variaram de 0,0022 a 0,0070 d-1 e os tempos de meia-vida variaram de 101 a 320 dias. Portanto, os resultados obtidos neste estudo demonstraram que a pectina e a proteína isolada de soja podem ser consideradas potenciais materiais de revestimento na microencapsulação de antocianinas a serem utilizados na indústria de alimentos. / The search for alternative sources of natural pigments has stimulated the development of research with different tropical fruits and their waste; in the present work, we chose to study the use of the bagasse generated in the production of jaboticaba juice was studied. Jaboticaba is a fruit rich in anthocyanins, a natural pigment, which besides the ability of providing color, also has beneficial health activities. However, its use as a natural colorant in the food industry, replacing the synthetic coloring agents is limited by their instability due to the process conditions and the presence of other components. An alternative to increase stability of anthocyanins is microencapsulation technique in which the sensitive ingredient is protected within the coating material. The present work aims the production, characterization and verification of the stability of the powders obtained by freeze-drying using maltodextrin, pectin and the isolate soy protein as wall materials in different proportions. The powders were analyzed for moisture content, water activity, solubility, hygroscopicity, particle size, morphology, thermal and colorimetric analysis, total phenolics content, total monomeric anthocyanin and capacity to scavenge the ABTS.+. They were also evaluated for stability in the presence of UV light during storage and compared with the lyophilized extract of anthocyanins not microencapsulated. Anthocyanins were extracted from jaboticaba pomace with ultrasound using water acidified with citric acid (1%) The concentrated extract anthocyanins showed an amount of monomeric anthocyanins of 510 ± 0.09 mg. 100g-1 a content of total phenolics of 12.860 ± 1.5 mg GAE.100g-1 and antioxidant activity of 39,590 ± 1.25 μM TE.g-1 pomace dry basis. In addition, the samples presented low moisture values (2.09 ± 0.10 to 4.15 ± 0.32%), low water activity (0.053 ± 0.003 to 0.162 ± 0.002) and hygroscopicity ranging from 10.8 ± 0.1 to 14.2 ± 0.3 g/100g as well as low solubility in water (10.86 ± 0.1 to 21.28 ± 0.2%) which are desirable attributes for food powder. Through the thermal analysis it was verified that the anthocyanins were effectively microencapsulated with the different coating materials tested due to the formation of new endothermic transitions; it was also observed that the powders showed a thermal stability up to 130 °C. The photostability the powders and extract of anthocyanins lyophilized not microencapsulated stored for 90 days showed that this pigment degradation followed a first-order kinetics. For the extract not microencapsulated the values obtained of degradation and half-life were equal to 0.0135 d-1 and 51 days, respectively, corresponding to a 77 % reduction of monomeric anthocyanins, 56% total phenolics content and 43 % of antioxidant capacity In contrast, the wall material protected the pigment against the deleterious effect of light in more than 90 % for total phenolic content and 80 % for the amount of monomeric anthocyanins, so the antioxidant activity remained at 70 % for the storage period. The rate constants according to a first-order reaction for all formulations ranged from 0.0022 to 0.0070 d-1 and the half-life times ranged from 101 to 320 days. Therefore, the results of this study showed that the pectin and the isolate soy protein can be potentially be used as coating materials in the microencapsulation of anthocyanins for use in the food industry.

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