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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.
11

The effects of octacosanol on conception and reproduction, on maintenance and growth of young, and on oxygen uptake in the white rat

Farrell, Patricia Rose. January 1966 (has links)
Call number: LD2668 .T4 1966 F245 / Master of Science
12

Encapsulation Of Wheat Germ Oil

Yazicioglu, Basak 01 February 2013 (has links) (PDF)
ABSTRACT ENCAPSULATION OF WHEAT GERM OIL Yazicioglu, Basak M.Sc., Department of Food Engineering Supervisor: Prof. Dr. Serpil Sahin Co- Supervisor: Prof. Dr. G&uuml / l&uuml / m Sumnu February 2013, 82 pages Wheat germ oil is a rich source of omega 3 and omega 6, octacosanol and tocopherol which has vitamin E activity. Due to these properties it is beneficial for health but it is prone to oxidation in free form. The aim of this study was to encapsulate wheat germ oil in micron size and determine the best encapsulation conditions by analysing encapsulation efficiency, particle size distribution and surface morphology of the capsules. The effects of core to coating ratio, coating materials ratio and ultrasonication time on encapsulation of wheat germ oil were investigated. Maltodextrin (MD) and whey protein concentrate (WPC) at different ratios (3:1, 2:2, 1:3) were used as coating materials. Total solid content of all samples was 40% (w/w). Five different core to coating ratios (1:8, 1:4, 2:4, 3:4, 4:4) were experimented. Ultrasound was used at 320 W and 20 kHz frequency for three different times (2, 5, 10 min). Prepared emulsions were frozen and then freeze dried for 48 hours to obtain microcapsules. Encapsulation efficiency analysis, particle size analysis and scanning electron microscopy (SEM) analysis were performed. Increasing WPC content in coating led to an increase in encapsulation efficiency. Microcapsules prepared with MD:WPC ratio of 1:3 were found to have higher encapsulation efficiencies (65.62%-89.62%) than the other ratios. Increase in oil load led to decrease in encapsulation efficiency thus 1:8 core to coating ratio gave better results. The best conditions for microcapsules were determined as ultrasonication time 10 min, core to coating ratio of 1:8 and MD:WPC ratio 1:3.
13

Antioksidacinio aktyvumo nustatymas preparatuose, turinčiuose omega – 3 riebalų rūgščių / Evaluation of antioxidant activity of preparations containing omega - 3 fatty acid

Kiškytė, Karolina 18 June 2014 (has links)
Darbo tikslas: nustatyti antioksidacinį preparatų, turinčių omega – 3 riebalų rūgščių, aktyvumą, palyginti jį su preparatų sudėtimis, atlikti vaistinės asortimento analizę. Darbo uždaviniai: Atlikti preparatų antioksidacinio aktyvumo tyrimą DPPH metodu. Atlikti preparatų palyginamąją analizę vertinant sudėtis. Išnagrinėti omega – 3 riebalų rūgščių turinčių preparatų pasiūlą vaistinėse. Metodai: antioksidacinis aliejų aktyvumas tirtas spektrofotometriškai naudojant 2,2-difenil-1-pikrilhidrazilo (DPPH) laisvojo radikalo sujungimo metodą. Pasirinktų linų sėmenų, kanapių sėklų, judros, rapsų, kviečių gemalų, graikinių riešutų aliejų bei žuvų taukų sudėtys vertintos ir lygintos literatūros analizės metodu. Tyrime naudotų aliejų paplitimas vaistinės asortimente nustatytas renkant duomenis vaistinėse bei elektroninėse vaistinių parduotuvėse. Rezultatai: nustatytas antioksidacinis aktyvumas (išreikštas inaktyvuoto DPPH % ±SD) kviečių gemalų aliejaus 53,59 ± 9,45, žuvų taukų 22,58 ± 5,38, judros aliejaus 22,40 ± 4,74, linų sėmenų aliejaus 22,17 ± 2,64, kanapių sėklų aliejaus 19,05 ± 1,54, graikinių riešutų aliejaus 18,66 ± 4,10, rapsų aliejaus 17,04 ± 2,68. Palyginus rezultatus ir literatūroje pateiktus duomenis nustatyta, kad nėra ryšio tarp aliejuje esančio omega – 3 riebalų rūgščių kiekio ir antioksidacinio aktyvumo, tačiau yra statistiškai patikimas ryšys tarp antioksidacinio aktyvumo ir sudėtyje esančio vit.E kiekio. Įvertinus vaistinės asortimentą nustatyti 75 žuvų taukų... [toliau žr. visą tekstą] / Objective of work: To estimate the antioxidant activity of preparations containing omega - 3 fatty acids; compare it with constitution of preparations; to execute the analysis of pharmacy range. Main tasks: to estimate the antioxidant activity by using DPPH method. To compare preparations by evaluating their constitutions. To execute the analysis of pharmacy range. Methods: antioxidant activity determined by using 2,2 – diphenyl-1-picrylhidrazyl free radical scavenging method. The constituents of flax seed, hemp seed, camelina, rapeseed, wheat germ, walnut and fish oil were evaluated by literature analysis. The data of prevalence of selected oils in pharmacy range was collected in the pharmacies and their online-shops. Results: antioxidant activity of wheat germ oil was 53,59 ± 9,45%, fish oil 22,58 ± 5,38%, camelina oil 22,40 ± 4,74%, flax seed oil 22,17 ± 2,64%, hemp seed oil 19,05 ± 1,54%, walnut oil 18,66 ± 4,10%, rapeseed oil 17,04 ± 2,68%. A comparison of the results showed that there is no significant relationship between amount of omega – 3 fatty acids and the antioxidant activity of the oil, but there is a statistically significant relationship between the amount of tocopherols and the antioxidant activity. The evaluation of the pharmacy range showed 75 fish oil products, 10 products containing flax seed oil, 9 wheat germ oil, 6 hemp seed oil, 3 products with camelina oil, 2 rapeseed oil, and only one product containing walnut oil. Conclusions: The highest... [to full text]
14

Ultrasound Assisted Extraction Of Lipids And Antioxidants From Wheat Germ

Melikoglu, Mehmet 01 February 2005 (has links) (PDF)
The aim of this thesis work was to extract lipids and antioxidants from wheat germ using an ultrasonic bath. Alternative solvents: Ethanol, isopropanol and acetone were used for the extraction purposes and for the fat content determination hexane was used. Alternative solvents dissolve wax, phospholipids and some other proteins because of their polar nature which increased the yield. Since waxes and some proteins can be added to the soaps and creams which were made from carrier oils, obtaining these substances together with the oil in the extract was very useful. For isopropanol a linear relation was found between the extract ratio and ultrasonication time. The highest extract ratios were achieved with ethanol. For 30 minutes of ultrasonication 0.10 g extract / g germ was obtained. After the extraction in order to enhance the phase separation between the solid phase (germ and other solids) and the extract phase, combinations of centrifugation, storage in the refrigerator and decantation were tested. The technique involving storage the extracts in the refrigerator for 24 hours and centrifugation at 2800 rpm for 20 minutes gave the second highest yield but the best phase separation. Ethanol extracts from both roasted and nonroasted wheat germs were characterized in terms of their total polyphenol contents. For non roasted wheat germs total polyphenol contents of 200 mg gallic acid / L solution and for roasted wheat germs an average of 170 mg gallic acid / L solution were obtained for 30 minutes of ultrasonic extraction. For nonroasted wheat germs weak but significant linear relations were found between total polyphenol contents of the extracts and ultrasonication time.
15

Pilot Scale Wheat Germ Stabilization In A Spouted Bed

Oymak, Mert Mehmet 01 May 2006 (has links) (PDF)
ABSTRACT PILOT SCALE WHEAT GERM STABILIZATION IN A SPOUTED BED OYMAK, Mert Mehmet M.S., Department of Chemical Engineering Supervisor: Prof. Dr. N. Suzan KINCAL Co-Supervisor: Dr. Cevdet &Ouml / ZTiN April 2006, 97 pages Wheat germ, a nutritionally rich by product of wheat milling, has poor storage stability due to its content of essential fatty acids along with oxidative enzymes. A pilot scale conventional spouted bed was designed and constructed as a high temperature &amp / #8211 / short time treatment unit to bring about drying and roasting effects. By facilitating the use of high temperature inlet air, yet maintaining the bed solids at a temperature below the degradation temperature, spouted bed dryers achieve thermal efficiencies unachievable by other dryers. The inlet diameter, diameter of the column and the angle of the cone were 6.2 cm, 16 cm and 65&deg / respectively. Thermocouples were placed on the inlet, exit and discharge gate of the column. Temperature profiles were recorded during drying, roasting and cooling of wheat germ. The drying temperatures ranged between 201 and 243&deg / C, operation times between 6.5 and 12 minutes, and air flow rate between 55 and 65 m3/h. It was seen that the degree of roasting was closely related to the exit temperature of the air. The exit air temperature range was determined as 155-160&deg / C. Sensory evaluation tests were carried out. Wheat germ processed at 60 m3/h &amp / #8211 / 209&deg / C for 12 min and 55 m3/h &amp / #8211 / 216&deg / C for 7 min were selected as the samples for storage studies, on the basis of the results of sensory evaluation tests. Reproducibility runs were carried out for the selected conditions. The bed height increase study was carried out at 60 m3/h &amp / #8211 / 240 to 243&deg / C. The processed and raw wheat germ was stored in paper pouches at 40&deg / C, to estimate the shelf life on the basis of earlier studies. Peroxide values of both raw and processed samples were followed during the storage period. The initial peroxide values of raw germ, processed samples, and reproducibility samples were 1.1 meq peroxide / kg oil. The peroxide value formation data were found to follow zero order rate kinetics. Comparison of the peroxide value changes in the processed and raw samples indicated that in the studied range of 55-60 m3/h &amp / #8211 / 209-216&deg / C &amp / #8211 / 7-12 min, about 8&amp / #8211 / 10 fold increase in the shelf life due to stabilization was achieved. The color parameters of each run were determined using the CIELAB (L*, a*, b*) system. Total color difference (&amp / #8710 / E*) values due to processing were calculated using L*, a* and b* values, to be between 2.3 and 58.6.
16

Ultrasound Assisted And Supercritical Carbon Dioxide Extraction Of Antioxidants From Roasted Wheat Germ

Gelmez, Nilufer 01 February 2008 (has links) (PDF)
This study covers the extraction of antioxidants from wheat germ / which is the byproduct of the flour-milling industry and a rich source of antioxidants / with Ultrasound Assisted (UAE) and Supercritical Carbon Dioxide (SC-CO2) extractions. Extraction conditions were ultrasonication time (1&ndash / 11 min), temperature (20&ndash / 60&deg / C) and ethanol level (5&ndash / 95%) for UAE, and pressure (148&ndash / 602 bar), temperature (40&ndash / 60&deg / C) and time (10&ndash / 60 min) for SC-CO2 extraction. The extraction conditions were optimized based on yield (%), total phenolic contents (TPC, mg GAE/g extract) and antioxidant activities (AA, mg scavenged DPPH&amp / #729 / /g extract) of the extracts, using Central Composite Rotatable Design. Total tocopherol contents (TTC) of the extracts were determined, as well. UAE (at 60&deg / C) with low ethanol level (~5-30%) and short times (1-3 min) provided protein rich extracts with high yield, medium TPC and AA. On the other hand, with high ethanol level (~90%) and long times (6-11 min), waxy structured extracts with low yield but high TPC and AA were obtained. SC-CO2 extraction at 442 bar, 40&ordm / C and 48 min. enabled almost 100% recovery of wheat germ oil (9% yield) but TPC and AA of the extracts were low. On the contrary, the extracts obtained at lower pressures (~150bar) and shorter times (~10 min) at 50-60&ordm / C had high TPC and AA since the oil yield was low. However, TPC and AA of these extracts were only half of those extracted by UAE. Maximum tocopherol (7.142 mg tocopherol/g extract) extraction was achieved at 240 bar, 56&ordm / C for 20 min. Both of the methods extracted high amounts of tocopherols from roasted wheat germ (SC-CO2 extraction / 0.31 mg tocopherol/g germ, UAE / 0.33 mg tocopherol/g germ) but TTC of the extracts obtained by SC-CO2 extraction was superior compared to 1.170 mg tocopherol/g extract obtained by UAE at 9 min, 58&ordm / C and 95% ethanol level. All these extracts with different characteristics have potential uses in cosmetic and food industry depending on the targeted specific application.
17

Valorizacija nutritivnog profila keksa proizvedenog sa dodatkom sporednih proizvoda prehrambene industrije / Valorization of the nutritional profile of cookies produced with the addition of food industry by-products

Petrović Jovana 22 May 2018 (has links)
<p>Zadatak ove teze je da se ispita uticaj zamene dela p&scaron;eničnog bra&scaron;na ekstrudiranim snek proizvodima obogaćenim dodatkom p&scaron;enične klice, pivskog tropa i tropa jabuke na svojstva testa (boja, fizička, reolo&scaron;ka) kao i na karakteristike čajnog peciva (fizičke, senzorske, nutritivne, trajnost, mikrobiolo&scaron;ke). U toku preliminarnih ispitivanja (prva faza eksperimentalnog rada) ispitan je uticaj obezma&scaron;ćene p&scaron;enične klice na kvalitet testa i čajnog peciva u cilju definisanja optimalnog nivoa zamene p&scaron;eničnog bra&scaron;na ekstrudatima kukuruzne krupice sa dodatkom sporednih proizvoda prehrambene industrije i optimalnog sadržaja vlage testa. P&scaron;enično bra&scaron;no je u količini od 5, 10 i 15 % zamenjeno obezma&scaron;ćenom p&scaron;eničnom klicom. Pored uticaja nivoa zamene p&scaron;eničnog bra&scaron;na p&scaron;eničnom klicom, ispitan je i uticaj veličine čestica p&scaron;enične klice (&lt;150 &mu;m, 150-1000 &mu;m i 800-2000 &mu;m), kao i vlage testa pri zamesu (20, 22 i 24 %). U toku druge faze eksperimentalnog rada ove doktorske disertacije, pripremljeni su ekstrudati kukuruzne krupice sa dodatkom sporednih proizvoda prehrambene industrije i to: p&scaron;enične klice, pivskog tropa i tropa jabuke u udelima 15, 30 i 45 % (odnos kukuruzna krupica:sporedni proizvod bio je 85:15, 70:30 i 55:45). Dobijeni ekstrudati su samleveni i prosejani na sitima u cilju dobijanja tri frakcije sa različitim veličinama čestica (&lt; 250 &mu;m, 250 - 1000 &mu;m i 1000 - 2000 &mu;m). Izvr&scaron;ena je karakterizacija ekstrudata u smislu određivanja hemijskog sastava, raspodele veličine čestica, boje i mikrobiolo&scaron;ke analize. Ovako dobijeni ekstrudati su zatim kori&scaron;ćeni u proizvodnji čajnog peciva kao zamena p&scaron;eničnog bra&scaron;na u količinama od 5, 10 i 15 % računato na masu bra&scaron;na. Za procenu uticaja veličine čestica ekstrudata, udela sporednog proizvoda u ekstrudatu i udela ekstrudata u čajnom pecivu na osobine testa i čajnog peciva takođe je kori&scaron;ćen Box-Behnken eksperimentalni dizajn. Rezultati su pokazali da je moguća proizvodnja funkcionalnog čajnog peciva sa dodatkom ekstrudata kukuruzne krupice obogaćene sporednim proizvodima prehrambene industrije, pri čemu se pobolj&scaron;ava nutritivni profil čajnog peciva, bez negativnih efekata na fizičke i senzorske karakteristike gotovog proizvoda.</p> / <p>The aim of this study is to examine the effect of replacing a portion of wheat flour with extruded snack products enriched with the addition of wheat germ, brewer&#39;s spent grain and apple pomace on the rheological and textural properties of dough and on characteristics of cookies (physical, sensory, nutritive, microbiological). During the preliminary analysis (the first phase of the experimental work), the influence of defatted wheat germ particle size, wheat germ content and dough moisture content on the quality of the dough and the cookies was investigated using the Box-Behnken experimental design. During the second phase of the experimental work, the extruded corn meal with the addition of by-products of the food industry (wheat germ, brewer&#39;s spent grain and apple pomace) were prepared (the ratio of corn meal: by-product was 85:15, 70:30 and 55:45). The obtained snack products are milled and sieved to obtain 3 fractions with different particle sizes (&lt;250 &mu;m, 250-1000 &mu;m and 1000-2000 &mu;m). Characterization of the extrudates in terms of determining the chemical composition, particle size distribution, color and microbiological analysis was performed. The obtained extrudates were then used in the production of cookies for the replacement of wheat flour in quantities of 5, 10 and 15%. The Box-Behnken experimental design was used to evaluate the influence of the extrudate particle size, the share of the by-product in the extrudate, and the share of extrudates in the cookies, on the dough properties and cookies characteristics.<br />The results showed that the corn snack products enriched with food industry by-products (brewer&#39;s spent grain, wheat germ and apple pomace) can be used for production of functional cookies. These additives in an amount up to 15% improving the nutritional profile of the cookies, without adverse effects on the physical and sensory characteristics of the final product.</p>
18

Desenvolvimento e estudo da estabilidade de barra de cereais de elevado teor proteico e vitaminico / Development and study of cereal bar stability of proteic and vitamic contents high

Freitas, Daniela De Grandi Castro 03 October 2005 (has links)
Orientador: Roberto Herminio Moretti / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-04T02:30:32Z (GMT). No. of bitstreams: 1 Freitas_DanielaDeGrandiCastro_D.pdf: 989026 bytes, checksum: c9f4c5d7a467d08716626299b2917043 (MD5) Previous issue date: 2005 / Resumo: Nutrientes são necessários para o desenvolvimento e crescimento dos indivíduos. No entanto, uma nutrição preventiva pode proteger, minimizar ou mesmo protelar riscos a saúde que podem ser causados por pré-disposições genéticas, maus hábitos alimentares e até agressões do meio ambiente. As evidências epidemiológicas estão continuamente providenciando recomendações para que as pessoas consumam mais frutas e vegetais como medida preventiva para reduzir o risco de diversas doenças degenerativas. É notável o aumento do consumo de alimentos saudáveis devido à crescente preocupação com a melhoria da qualidade de vida, porém, o ritmo da vida moderna exige alimentos práticos. Dentro deste contexto, do crescimento visível do desenvolvimento de alimentos para fins especiais, da necessidade de combinar saúde e praticidade, e de reunir alguns ingredientes que vem recebendo grande atenção para a aplicação nestes alimentos funcionais, é que se elaborou o estudo de desenvolvimento e estabilidade de barra de cereais a base de proteína de soja, gérmen de trigo e aveia, incluindo como ingrediente a lecitina de soja, e suplementada com vitaminas C e E. Este trabalho teve por objetivo o desenvolvimento da formulação da barra de cereais e a avaliação das características físico-químicas, vitamínicas, enzimáticas, sensoriais e de textura durante o seu armazenamento. Um estudo preliminar de inativação enzimática no gérmen de trigo foi realizado devido à susceptibilidade a rancidez, fator adverso de qualidade de cereais desidratados. Amostras de aveia laminada integral e gérmen (produto natural inalterado da moagem do trigo) foram caracterizadas e a atividade de lipase e peroxidase medidas. Foi utilizado um delineamento fatorial completo para estudar os efeitos dos fatores ¿temperatura¿ e ¿tempo¿ na inativação das enzimas e para a determinação das condições ótimas de redução de atividade no gérmen de trigo. Foram determinadas como condições ótimas tratamentos térmicos à temperatura na faixa de 180 a 190°C, com duração de 4,8 a 8,0 minutos e obtidas reduções significativas (p£0,5) na atividade residual da lipase e peroxidase. O gérmen de trigo teve seu teor de umidade ajustado para 28% e a torração foi realizada em estufa a 180°C por 8,0 minutos, para que pudesse ser utilizado como ingrediente da barra de cereais. Desenvolveu-se então uma formulação de barra de cereais funcional sabor banana com alto teor protéico, à base de proteína de soja, gérmen de trigo e aveia, e enriquecida de vitaminas C (ácido ascórbico) e E (acetato de a-tocoferol 50%). A barra de cereais e seus principais ingredientes foram submetidos a análises físico-químicas para caracterização e três formulações variando o teor de ácido ascórbico foram avaliadas quanto à aceitação sensorial e intensidade ideal de doçura e acidez. A proteína de soja texturizada utilizada apresentou elevados teores dos oligossacarídeos rafinose e estaquiose (1,92 g/100g e 4,66 g/100g) e de isoflavonas totais (283,49 mg/100g) se comparados ao grão, farinha integral e isolado protéico. A formulação final da barra de cereais apresentou 15,31% de proteína e elevado teor de vitamina E (118,0 mg/100g) e minerais como fósforo (P), cálcio (Ca), cobre (Cu), ferro (Fe), manganês (Mn) e zinco (Zn). A formulação adicionada de 1,1g/100g de ácido ascórbico obteve maior aceitação sensorial diferindo significativamente (p£0,5) das demais amostras. Esta formulação, preferida pela equipe sensorial, foi então submetida ao estudo de estabilidade durante o seu armazenamento. Foram utilizados como embalagens três filmes (A: PET/PEBD; B: PETmet/PEBD; C: PET/PEBD/AL/PEBD) com diferentes propriedades de barreira. As barras de cereais foram armazenadas em condições de temperatura e umidade relativa ambiente por um período de 180 dias. Durante o armazenamento, estudou-se a estabilidade das vitaminas C, vitamina E, e a atividade de lipase e peroxidase. No período de 180 dias, as barras de cereais acondicionadas nos três materiais testados apresentaram uma retenção de vitamina C menor que 50%. No entanto, a embalagem com folha de alumínio proporcionou menor velocidade de reação e maior tempo de meia vida de 146 dias. Os teores de vitamina E (acetato de a-tocoferol) nas barras de cereais apresentaram pequenas variações durante o armazenamento. Houve um aumento significativo (p£0,5) da atividade de peroxidase durante o período de 90 dias de estocagem nas embalagens testadas, provavelmente devido à regeneração dessa enzima, enquanto que a atividade de lipase não demonstrou aumento significativo durante os 180 dias de estocagem. Foram acompanhados também a umidade, atividade de água, pH, acidez total e medidas físicas associadas à textura como resistência ao corte, dureza e coesividade. A avaliação sensorial foi realizada através de teste de aceitação e intenção de compra durante o armazenamento. As barras de cereais formuladas com os ingredientes alternativos apresentaram variações na atividade de água (Aa), umidade e acidez total durante o armazenamento. A umidade das barras de cereais tendeu a um aumento, o que acarretou influência significativa (p£0,5) nas características de textura de resistência ao corte e dureza. As barras de cereais formuladas com proteína texturizada de soja, gérmen de trigo e aveia obtiveram boa aceitação sensorial perante consumidores nos atributos de sabor e aspectos visuais, porém, a aceitação tendeu a um declínio ao longo do tempo, associado à diminuição da intenção de compra do produto. O efeito das diferentes propriedades de barreira dos filmes de embalagens testados foi significativo (p£0,5) na estabilidade das barras de cereais ao longo do período de estocagem / Abstract: Nutrients are required for development and growth of individuals. However a preventative nutrition could be protected, minimized or delayed by way from health risks arising from genetic aggressions, the environment and also eating habits. Epidemiological evidence is constantly providing recommendations that people should consume more fruits and vegetables as a preventative measure to reduce the risk of various degenerative diseases. The increase in consumption of health foods is notable, due to the increasing concern with the improvement of life quality, although the pace of modern life demands practical foods. Within this context of a visible growth in the development of foods for special ends, of the need to combine health and practicality and aiming to bring together some ingredients which have received special attention for application in such functional foods, a study of the development and stabilization of a cereal bar based on soy protein, wheat germ and oat was elaborated, with the addition of soy lecithin and supplemented with vitamins C and E. Thus the objective of this study was the development and formulation of a cereal bar and an evaluation of its physicochemical, vitamin, enzymatic, sensory and texture characteristics during storage. A preliminary study of the enzymatic inactivation of wheat germ was carried out due to its susceptibility to rancidity, a process reducing the quality of dehydrated cereals. Samples of whole rolled oats and wheat germ (natural, unaltered product from wheat milling) were characterized and their lipase and peroxidase activities determined. A complete factorial design was used to study the effects of time and temperature in the inactivation of the enzymes and to determine the optimal conditions to reduce their activity in wheat germ. The optimal conditions were shown to be a temperature in the range from 180 to 190°C for between 4.8 and 8.0 minutes, obtaining significant (p£0,5) reductions in the residual activities of lipase and peroxidase. The moisture content of the wheat germ was adjusted to 28%, which was then roasted at 180°C for 8.0 minutes such that it could be used as an ingredient in cereal bars. A functional, banana flavored cereal bar was formulated with high protein content, based on soy protein, wheat germ and oat, and enriched with vitamins C (ascorbic acid) and E (50% a-tocopherol). The cereal bar and its main ingredients were characterized by way of physicochemical analyses, and three formulations, varying in their ascorbic acid contents, prepared and submitted to a sensory acceptance test and ideal test for the intensity of sweetness and acidity. The textured soy protein used showed high contents of the oligosaccharides raffinose and stachyose (1.92 g/100g and 4.66 g/100g) and of total isoflavones (283.49 mg/100g) as compared to the bean, whole flour and protein isolate. The final formulation of the cereal bar showed 15.31% protein and high contents of vitamin E (118.0 mg/100g) and minerals such as phosphorus (P), calcium (Ca), copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn). The formulation with 1.1 g/100g of ascorbic acid was the most accepted sample, differing significantly (p£0,5) from the other samples. This most accepted formulation was submitted to an evaluation during storage. Three films were used for packaging: (A: PET/PEBD; B: PETmet/PEBD; C: PET/PEBD/AL/PEBD), each with distinctive barrier properties. The cereal bars were studied under environmental conditions of temperature and relative humidity for 180 days. Vitamins C and E stabilities and the activities of lipase and peroxidase were determined during storage. The cereal bars packaged in the three materials tested showed vitamin C retention below 50% after 180 days storage. However the packaging including aluminum foil provided a lower reaction velocity and longer half life of 146 days. The vitamin E (a-tocopherol acetate) contents of the cereal bars presented slight variations during storage. There was a significant increase in peroxidase activity during the first 90 days of storage in all the types of packaging tested, probably due to regeneration, whilst lipase activity showed no significant increase during the 180 days of storage. The moisture content, water activity, pH and total acidity were also determined during storage as well as the textural measurements of cutting resistance, hardness and cohesiveness. The acceptance and intention to buy tests were used for the sensory evaluation during storage. The cereal bars formulated with alternative ingredients showed variations in water activity (Aw), moisture content and total acidity during storage. The moisture contents of the cereal bars tended to increase during storage, with a significant (p£0,5) influence on the textural characteristics of cutting resistance and hardness The cereal bars formulated with textured soy protein, wheat germ and oats were well accepted by the consumers in the sensory evaluation (flavor and visual aspect), although the acceptance tended to decline during storage, associated with a decrease in intent to buy. The effect of the different barrier properties of the packaging films tested was significant (p£0,5) in the stability of the cereal bars during storage / Doutorado / Tecnologia de Alimentos / Doutor em Tecnologia de Alimentos
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3D-electron microscopic characterization of interstitial cells in the human bladder upper lamina propria

Neuhaus, Jochen, Schröppel, Birgit, Dass, Martin, Zimmermann, Hans, Wolburg, Hartwig, Fallier-Becker, Petra, Gevaert, Thomas, Burkhardt, Claus J., Minh Do, Hoang, Stolzenburg, Jens-Uwe 19 February 2018 (has links)
1) Aims To explore the ultrastructure of interstitial cells in the upper lamina propria of the human bladder, to describe the spatial relationships and to investigate cell-cell contacts. 2) Methods Focused ion beam scanning electron microscopy (FIB-SEM), 3-View SEM and confocal laser scanning microscopy were used to analyze the 3D ultrastructure of the upper lamina propria in male and female human bladders. 3) Results 3View-SEM image stacks as large as 59µm x 59µm x 17µm (xyz) at a resolution of 16nm x 16nm x 50 nm and high resolution (5nm x 5nm x 10nm) FIB-SEM stacks could be analyzed. Interstitial cells with myoid differentiation (mIC) and fibroblast like interstitial cells (fIC) were the major cell types in the upper lamina propria. The flat, sheet-like ICs were oriented strictly parallel to the urothelium sheet-like morphology. No spindle shaped cells were present. We furthermore identified one branched cell (bIC) with several processes contacting urothelial cells by penetrating the basal membrane. This cell did not make any contacts to other ICs within the upper lamina propria. We found no evidence for the occurrence of telocytes in the upper lamina propria. 4) Conclusions Comprehensive 3D-ultrastructural analysis of the human bladder confirmed distinct subtypes of interstitial cells. We provide evidence for a foremost unknown direct connection between a branched interstitial cell and urothelial cells of which the functional role has still to be elucidated. 3D-ultrastructure analyses at high resolution are needed to further define the subpopulations of lamina propria cells and cell-cell interactions.
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Illumination of the Golgi apparatus of Pathogenic and Nonpathogenic Naegleria species

Poe, Tyler M, Marciano-Cabral, Francine 01 January 2019 (has links)
In this study, Naegleria fowleri, a pathogenic amoeba and the causative agent of Primary Amebic Meningoencephalitis (PAM), was utilized to determine the presence or absence of classically conserved Golgi molecules featured in the expression of a Golgi apparatus. Previous studies concluded no Golgi expression via light microscopy and transmission electron microscopy, but a recent report on Naegleria gruberi indicated the presence of dispersed Golgi tubules. Non-pathogenic species of the Naegleria genus such as Naegleria gruberi 30540 and Naegleria lovaniensis 30569 were utilized in Western immunoblot analysis compared to reduced whole-cell lysate proteins of two strains of N. fowleri and Vero CCL-81, Chlorocebus sp. kidney epithelial cells, which were utilized as a positive control for Golgi expression. N. fowleri and N. lovaniensis whole-cell lysates had indications of a 110 kDa reduced protein, associated with the predicted molecular weights of the beta-COPI subunit of the COPI cis-Golgi vesicular transport complex with further Western immunoblot indication of a weak band around 25 kDa corresponding to rabbit polyclonal antibodies specific for ARF1. Serial Dilutions of Wheat Germ Agglutinin Alexa Fluor 488TM were performed on Vero cells, Naegleria fowleri 30894, and N. gruberi 30540 with 1:100 dilution of recommended stock dilution of WGA 488 determined for utilization in sequential immunofluorescence. Sequential immunofluorescence with Wheat Germ Agglutinin Alexa Fluor 488TM and then blocked with 3% BSA:PBS [wt/vol] dilution with subsequent incubation in rabbit anti-beta-COPI primary 1:250, and 1:1000 of Alexa Fluor 594 goat anti-rabbit secondary antibody exposure showed strong indications of organized cis- and trans-punctate Golgi body markers in close association in individual and dividing cells of Naegleria fowleri and conserved Golgi expression in the positive control Vero cells, but further experiments are necessary to verify this finding with N. fowleri.

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