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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.
71

Process for the preparation of cis- AND trans-3,7-Dimethyl 2,6-Octadiene-1-OL from crude sulphated turpentine stream

Sathikge, Ndavheleseni David January 2008 (has links)
As part of CSIR Biosciences’ interest in aroma chemicals, the processing of crude sulphated turpentine (CST) into high value aroma products was investigated. The primary target product, linalool, was obtained from a mixture of α- and β-pinene in four steps. It can be transformed into a wide range of high value added aroma chemicals. Isomerisation of linalool in the presence of a transition metal catalyst furnishes geraniol and nerol. The scientific work described in this report was part of a bigger project aimed at developing innovative processes to manufacture aroma, flavour & fragrance chemicals through beneficiation of industrial waste streams and other raw materials, available locally from the Forestry, Paper & Pulp industries. The evaluation of a process for the preparation of precursor aroma, flavour & fragrance compounds, in particular geraniol and nerol, from locally available raw materials and industrial waste streams, was investigated. Preparation of geraniol and nerol from linalool (ex α-pinene stream) was investigated using acids or organometallic complexes as catalysts for the corresponding isomerisation reaction. The investigation was conducted in an effort to find a less costly process utilising milder conditions than via the conventional cleavage of β-pinene to myrcene under extreme pyrolysis conditions (>650°C). The transformation of linalool to geraniol/nerol using mineral acids was found to be dominated by secondary reactions such as dehydration and cyclisation, resulting in poor product selectivities and yields. On the other hand, organometallic complexes, in particular vanadium-based complexes (e.g. (OV(OBu)3) produced satisfactory results in the preliminary assessment (conversion of 79.8 percent and selectivity of 98.3 percent). A set of statistically designed experiments was carried out on the (VO(BuO)3 + [(Bu)4N+]OH¯) catalyst system where three variables were tested, i.e. substrate concentration, temperature, and catalyst loading. The selected model for conversion was significant with the “Probability > F” being < 0.0001. The most important contributing variable to the model for conversion was temperature i.e. 83.9 percent. Temperature was still the most important variable for the selectivity response at 65.0 percent contribution level. The response surface generated for the selectivity response was flat indicating a robust method within the parameter range selected.
72

Efeitos da incorporação de isolado proteico de soja e plasma bovino desidratado nas caracteristicas de um produto reestruturado de frango / Effects of incorporating soy protein isolate and dried bovine plasma in features of a product restructured chicken

Vega Malinconi, Jose Antonio de la 21 January 1985 (has links)
Orientador : Pedro Eduardo Felicio / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos e Agricola / Made available in DSpace on 2018-07-16T12:38:35Z (GMT). No. of bitstreams: 1 VegaMalinconi_JoseAntoniodela_M.pdf: 5110322 bytes, checksum: 0b6a706d0533bda1aaced109cbd26ae9 (MD5) Previous issue date: 1984 / Resumo: As técnicas de reestruturaçãode carne estão tendo uma grande importância no desenvolvimento da indústria avícola moderna. A elaboração de produtos reestruturados permite apyoveitar cortes ou carcaças de inferior valor comercial e, além disso, permite o emprego de derivados protéicos não cárneos, que podem contribuir para melhorar algumas qualidades do produto e, também, reduzir o seu custo de produção. No presente estudo foram investigadas as tendências dos efeitos da incorporaçãode plasma bovino desidratado (PBD) e isolado protéico de soja (IPS), em algumas características e organolépticas de um produto reestruturado de frango. físicas e organolepticas de um produto reestruturado de frango. Os produtos foram elaborados com a carne e a pele, proveniente da desossa manual, de peito, coxa e sobrecoxa de carcaças de frango. A carne foi moida e misturada, por 3 minutos, com uma pré-mistura contendo a pele, água, IPS e/ou PDB, e os condimentos da formulação correspondente. A massa assim preparada foi moldada usando uma máquina de hamburguer Hollymatic e as porções obtio das (55 g) foram congeladas e armazenadas a -30 C. A incorporaçãodo PBD e do IPS, combinada ou separadamente, no produto foi realizada seguindo um critério de substituição da proteína da carne, em níveis de O, 5 e 10%, pela proteína do PBD ou do IPS, chegando-se a substituir até 20% da carne quando empregou-se combinadamente PBD e IPS. Nas diferentes formulações usadas neste estudo, procurou-semanter a mesma relação umidade/proteína. Os efeitos do PBD e do IPS foram testados para as seguintes características do hamburguer: perda de peso e retração no cozimento, força máxima de cisalhamento do produto cozido, cor objetiva (luminosidade, teor de vermelho e teor de amarelo) e subjetiva (avaliação visual) do produto cru e cozido, mastigabilidade, suculência, condimento, sabor estranho e aceitação geral. As tendências mais relevantes dos efeitos da incorporaçao de PBD e de IPS, no hamburguer, podem ser assim resumidas: a) A incorporação de PBD mostrou um efeito mais acentuado do que o IPS na redução da perda de peso e retração do hamburguer durante o cozimento, mas, ao contrário do IPS, que aumentou a força máxima de cisalhamento, o PBD não influiu nessa característica do produto. b) As diferenças da cor objetiva devida à da incorporação de PBD e IPS foram relativamente pequenas, não influindo na preferência para cor do hamburguer cru e cozido. c) Ao incorporar separadamente, plasma ou soja no hamburguer, o PBD mostrou efeitos de aumento na mastigabilidade e de diminuição na aceitação geral, não influindo na intensidade da suculência; entretanto, o IPS mostrou um efeito de diminuição da suculência e nao influiu na mastigabilidade nem na aceitação geral do produto. d) A incorporação de PBD e do IPS, mostrou tendências, ainda que em intensidades baixas, de aumentar o sabor estranho no hamburguer. e) A incorporação de PBD e IPS não prejudicou a aceitação geral do hamburguer, registrando sempre intensidades de aceitação superiores ao valor considerado aceitável / Abstract: The restructured meat technology is receiving considerable attention in the development of the modern poultry industry. The manufacture af restructured poultry products allows utilization of cuts and carcasses of low commercial value, besides, making possible the use of non meat proteins that can improve some of the products guality characteristics and reduce cost. In this study the effects of the incorporation of dehydrated bovine plasma (DBP) and soy protein isolate (SPI) werE investigated, with regard to some physics and sensory characteristics of a restructured chicken product. The products were manufacture with meat and skin obtained from hand deboning of breast, thigh and drumstick of chicken. The meat was minced and homogenized for 3 minutes with a pre-blended mixture of skin, water, DBP and/or SPI, and seasonings correspondent to each specific formuIation. This meat mixture was molded into patties using a H01lymatic hamburguer machine; and the portions obtained (55 g) were frozen and stored at -30 oCo. The incorporation of DBP and SPI, combined or separateIy, to the product, was performed substituing the meat protein, at "levels of O, 5 and 10%, by the protein of DBP or by the SPlj when both, DBP and SPI, were incorporated together, it was at a maximum leveI of 20% of meat. In the different formu1ations used in this study, the same relation water/protein was kept throughout. The effects of the DBP and the SPI of the patties, were evaluated on the basis of the following parameters: weight 10ss and cook shrinkage, shear force, objective color (luminance, red and yellow values), subjective color (visual evaluation), che,'liness, juiciness, seasoning, off-flavor and overall acceptability. The most impqrtant effects of the incorporation of DBP and the SPI in the patties, can be outlined as follow: a) The incorporation of DBP showed to be better than the SPI in relation to the reduction of the weight losses and shrinkage of the patty during cooking, but, differently from SPI, it did not affect the shear force of the product. The SPI increased the shear force. b} The objective co1or differences due to the incorporation of DBP and SPI, were relatively small, in such away that the panelists could not detect any difference. c) When incorporated, separatedly, to the patties, the DBP showed an increased effect on the chewiness and a decreased effect on the overall acceptability values without influencing juiciness; on the other hand the SPI showed a decreased effect on the juiceness and did not influence the chewiness and overall acceptability. d) The addition of either DBP or SPI, tended to increase off-flavor in the patty, although at 100 intensities. e) The addition of DBP and SPI did not harm the overall acceptability of the patty, showing always scores above the value considered acceptable / Mestrado / Tecnologia de Alimentos / Mestre em Tecnologia de Alimentos
73

Substituição do milho moído por co-produtos da indústria de processamento do ácido cítrico em dietas de terminação de bovinos em confinamento / Replacing ground corn with citric acid industry by-products in finishing cattle diets

Murillo Alves Porto Meschiatti 06 July 2015 (has links)
O objetivo desse experimento foi avaliar a inclusão (7 e 15% com base em MS), de 2 co-produtos, derivados da indústria de ácido cítrico: Micélio (77% de FDN e 0,5% de lignina com base em MS) e Raffinate (25,5% de açúcares solúveis e 32% de fibra solúvel com base em MS) em dietas com alto teores de milho do tipo Flint para 200 tourinhos Nelore em terminação (peso inicial = 396,4 ± 37,7kg). Os animais foram blocados com base no peso inicial e foram distribuídos aleatoriamente em 25 baias. A dieta controle conteve 11,73% de bagaço de cana de açúcar, 67,2% de milho moído, 18% de farelo proteinoso de milho, 2,07% de suplemento mineral e 1% de ureia. Os outros 4 tratamentos foram: Micélio 7, Micélio 15, Raffinate 7 e Raffinate 15. Os co-produtos substituíram parcialmente o milho nas dietas. Os parâmetros avaliados foram ingestão de matéria seca (IMS), ganho médio diário (GMD), eficiência alimentar (GMD/IMS) e características de carcaça. Os dados foram analisados pelo PROC MIXED do SAS e as médias foram comparadas por contrastes, considerando blocos como efeito aleatório e tratamento como efeito fixo. A inclusão de 7 e 15% de Micélio na dieta (base seca) em substituição parcial ao milho \"flint\" moído aumentou (P=0,1) de forma quadrática o CMS. Já os animais alimentados com dietas contendo Raffinate apresentaram aumento linear no CMS (P<0,1) em relação ao tratamento controle e também maior CMS quando comparados com os animais que receberam o tratamento Micélio (P<0,1). Não houve diferença na eficiência alimentar (GPD/CMS) entre os tratamentos (P > 0,1). A inclusão de ambos co-produtos (Micélio ou Rafinatte) resultou em aumento no GDP dos animais (P< 0,1). O efeito positivo foi quadrático (P<0,1) para a inclusão de Micélio e linear (P<0,1) para a inclusão de Raffinate. A densidade energética das dietas não foi alterada pela inclusão de co-produtos. Não houve efeito de tratamento (P> 0.01) para as características de carcaça. Os valores médios para rendimento de carcaça (%), espessura de gordura subcutânea (mm) e áreas de olho de lombo (cm2) foram 53,79, 2,84 e 64,08 respectivamente. A inclusão de 7% de Micélio ou de 15% de Raffinate melhora o GPD dos animais em virtude do maior CMS. Micélio, Rafinate e milho \"flint\" moído têm o mesmo valor energético para bovinos em Terminação. / The objective of this experiment was to evaluate the inclusion (7 and 15%, DM basis) of two corn by-products derived from the citric acid industry: Micelio (77% NDF, 0.5% lignin, DM basis) and Raffinate (25.5% soluble sugars, 32% soluble fiber, DM basis) in diets with high levels of flint corn fed to 200 finishing Nellore bulls (initial BW = 396.4 ± 37.7 kg). Animals were blocked according to initial BW and randomly allocated to 25 pens. The control diet contained 11.73% sugarcane bagasse, 67.2% corn, 18% corn gluten feed, 2.07% mineral supplement and 1% urea. The other four treatments were Micelio 7, Micelio 15, Raffinate 7 and Raffinate15. The by-products partially replaced corn in the diets. The parameters evaluated were dry matter intake (DMI), average daily gain (ADG), feed efficiency (ADG/DMI) and carcass traits. The data were analyzed using PROC MIXED of SAS and means were compared by contrasts, considering the block as random effect and treatment as fixed effect. The inclusion of 7 and 15% of Micelio in the diet (dry basis) in partial replacement of ground corn increased (P = 0.1) DMI quadratically. The animals fed diets containing Raffinate showed linear increase in DMI (P <0.1) compared to the control treatment and DMI was, also higher when compared with animals that received the Micelio treatment (P <0.1). There were no differences in feed efficiency (ADG / DMI) among treatments (P> 0.1). The inclusion of both by-products (Micelio or Rafinatte) resulted in an increase in ADG animals (P <0.1). The positive effect is quadratic (P <0.1) for adding Micelio and linear (P <0.1) for adding Raffinate. The energy density of the diet was not altered by the inclusion of by-products. There was no treatment effect (P> 0.01) for carcass traits Average values for dressing (%), back fat thickness (mm) and rib eye area (cm2) were 53.79, 2.84, and 64.08, respectively. The inclusion of 7 or 15% of Micelio or Raffinate in partial replacement of ground flint corn in finishing diets does not affect cattle performance. The inclusion of 7% of Micelio or a 15% Raffinate improved ADG of animals because of the increased DMI. Micelio, Raffinate and ground corn have the same energy value for cattle finishing.
74

Problematik vid kontroll av animaliska biprodukter / Problems within government authority control of animal by-products

Kinnunen, Emma January 2021 (has links)
Animal by-products (ABPs) can be a source for infectious diseases like BSE (mad cow disease) and to prevent spreading infectious diseases inspection of ABPs are necessary. The purpose of this study was to identify the problems that municipalities in Sweden experience with the inspection of ABPs and develop some solutions for these problems. The purpose was also to investigate whether amount and type of problems experienced by municipalities are depending on population size. The study was carried out in collaboration with Piteå municipality, with the aim to support municipalities and other central authorities in their work with inspection of ABPs. Data were collected through a survey that was sent to all municipalities in Sweden and approximately 60% of the municipalities participated in this study. Lack of knowledge, lack of time due to high workload and lack of support from central authorities were some of the most common problems that municipalities experienced. As a consequence, inspections get down prioritized or are not carried out at all. The study shows that there is a significant difference in the amount of problems that municipalities experience depending on the population. Large municipalities experience more problems than small and medium sized municipalities. The study also shows how municipalities can identify companies that manage ABPs. This study highlights that municipalities urgent need effective guidelines and support from central authorities, otherwise the control of ABPs is neglected, which - in worst case scenario - can lead to outbreaks of infectious diseases.
75

Economics of bio-ingredients production from shrimp processing waste in Newfoundland

Tackie, Richard January 2002 (has links)
No description available.
76

The land application of cranberry presscake /

Akin, Thomas J. 01 January 2000 (has links) (PDF)
No description available.
77

Characterization, utilization and treatment of mechanized clam processing wastes

Libelo, Edward Laurence January 1988 (has links)
In response to water quality deterioration caused by clam processing effluent, the Virginia State Water Control Board is imposing much greater effluent discharge limitations on the industry. Meeting these limits will require increased wastewater treatment and decreasing the water volume of water used and the loading of organic material and suspended solids. Disposal of sludges and solid wastes also present problems to the industry. Three processing plants were studied to characterize the nature, sources and variations in waste generation and to evaluate potential solutions. Wastewater is generated throughout the processing plants from washing operations, from splashing and overflow of tanks and flumes and from cleanup operations. Wastewater generation varied from plant to plant and at each plant over time, ranging from 80,000 gallons to almost 350,000 gallons per day and as high as 40,000 gallons per hour. The organic loading in wastewater ranged as high as 15,000 mg/L COD and averaged 3000-7000 mg/L. Total suspended solids loading ranged as high as 29,000, and were usually between 1,000 and 10,000 mg/L. Anaerobic digestion and composting of solid wastes were evaluated by bench scale experiments. Anaerobic digestion can provide reduction in COD of 75% and generate usable biogas. Composting can be used to stabilize sludges and solid wastes with destruction of the organic fraction in seven days. The proposed 90 mg/L BOD and 90 mg/L TSS limitations are not significantly stricter than the limitations imposed on similar plants in other areas. / Master of Science
78

Optimization of sweet sorghum processing parameters

Weitzel, T. Timothy January 1987 (has links)
Production of fuel ethanol from renewable biomass sources has gained popularity in recent years. Sweet sorghum is one of the crops identified as an efficient producer of the sugars needed for ethanol production. The juice in the sweet sorghum pith contains the greatest proportion of nonstructural carbohydrates, the presumed fermentable material. Sugar cane milling procedures have previously been used to extract the juices from the sweet sorghum plant material. The research reported herein relates to a new method of juice extraction expected to provide higher juice expression efficiencies than previous methods. The sweet sorghum stalks are chopped and the sugar-laden pith fraction is separated from the fibrous rind-leaf. The pith portion only is then fed through a screw press for juice extraction. Several chopping and separating parameters were evaluated. A statistical linear regression analysis was employed to evaluate the effects of feed rate, cutting interval, chopper knife speed, and percent of whole stalk mass segregated into the pith category on juice yield. The analysis revealed that the pith category had the most significant positive effect on juice yield calculated as a percent of whole stalk mass. The highest pith categories provided optimization of juice expression. Feed rate has a negative effect on juice yield, meaning that slower feed rates were better, but this was the least significant parameter. The chopping interval had a positive effect, meaning that the largest value used in the analysis provided for optimum juice yield. The cutting speed parameter has no effect on juice yield. / Master of Science
79

Chemical Identification and Flavor Profile Analysis of Iodinated Phenols Produced From Disinfection of Spacecraft Drinking Water

Mirlohi, Susan 16 January 1998 (has links)
The National Aeronautics and Space Administration (NASA) is considering the use of iodine for disinfection of recycled wastewater and potable water in the International Space Station (ISS). Like Chlorine and other halogen compounds, iodine can form disinfection by-products (DBPs) in the presence of organic compounds. Recycled wastewater sources proposed for reuse in the space station include laundry, urine, and humidity condensate. These contain large concentrations of iodine-demanding compounds, including phenol (Barkely et al., 1992). Therefore, the potential for the formation of iodine disinfection by-products (IDBPs) is of concern. Based on the characteristics of the ISS recycled wastewater sources and potable water treatment system, a series of experiments was designed to evaluate the formation of IDBPs under different experimental conditions. Studies were conducted by reacting various concentrations of iodine with phenol at pH 5.5 and 8.0.Iodine concentrations of 10 and 50 mg/L and phenol concentrations of 5 and 50 mg/L were used. Reactions were monitored for up to 32 days for the formation of IDBPs. All reactions were maintained at 20 C in dark. High Performance Liquid Chromatography (HPLC) and Gas Chromatography/Mass Spectrometry (GC/MS) were used for identification and quantitative analysis of phenolic compounds. Spectrophotometry was used to monitor the iodine concentrations. Falvor Profile analysis (FPA) method was used to evaluate the odor characteristics of the phenolic compounds. Reactions of iodine with phenol resulted in the formation of the following by-products: 2-iodophenol, 4-iodophenol, diiodophenols, and 2,4,6-triiodophenol. Most reaction conditions studied resulted in the formation of all or some of the specified iodophenols. The initial mass ratio of iodine to phenol was the major determining factor in the concentrations and types of by-products formed. The IDBPs were formed within one hour after initiation of the reactions. Extended reaction times did not lead to significant increases in the concentration of IDBPs. Under most reaction conditions, mono-subsituted phenols were detected at significantly higher concentrations than di-substituted phenolic compounds; triiodophenol was the major by-product when iodine:phenol mass ratio was 10:1. The greatest number of IDBPs were formed when reaction solutions consisted of 1:1 mass ratio of iodine to phenol. FPA panel indicated the odor threshold concentrations for phenol, 2-iodophenol, and 4-iodophenol were 5 mg/L, less than 1 ug/L, and 1 mg/L respectively. The most common odor descriptions for all these compounds were &quot;chemical&quot;, &quot;phenolic&quot;, and &quot;medicinal&quot;. / Master of Science
80

Development of antioxidant dietary fibers from wine grape pomace and their applications as functional food ingredients

Tseng, Angela Y. 18 December 2012 (has links)
Wine grape pomace (WGP), the byproduct from winemaking, is a good source of polyphenols and dietary fibers, and may be utilized as antioxidant dietary fibers (ADF) for food applications. The objectives of this thesis research were to first determine the phenolic compounds, antioxidant and antimicrobial activities in red WGP under different drying processes for long-term storage, and to further evaluate the feasibility of using WGP as a functional food ingredient in yogurt and salad dressing for enhancing the nutritional value and improving storability of the products. Two types of WGP samples, pomace containing seeds and skins (P) and pomace with skins only (S) from Pinot Noir (PN) and Merlot (M) were studied. Samples were subjected to four different drying conditions: 40 °C conventional and vacuum oven, 25 °C ambient air and freeze dry. Total phenolic content (TPC, by Folin-Ciocalteu assay), anthocyanins (ACY, by pH differential method) and flavanols content (TFC, by vanillin assay) of the samples along with their antioxidant activity (DPPH radical scavenge method, RSA) and antibacterial activity (minimum inhibition concentration, MIC) were determined during 16 weeks of storage under vacuum condition at 15±2 °C. Meanwhile, dietary fiber profile was evaluated by using gravimetric-enzyme method. Results showed that dietary fiber contents of PN-P, PN-S, M-P and M-S were 57-63% d.m. with the majority of insoluble fraction. Freeze dried WGP retained the highest bioactive compounds with TPC 21.19-67.74 mg GAE/g d.m., ACY of 0.35-0.76 mg Mal-3-glu/g d.m., TFC of 30.16-106.61 mg CE/g d.m. and RSA of 22.01-37.46 mg AAE/g d.m., followed with ambient air dried samples. Overall, TPC, TFC and RSA were higher in PN than in M, and higher in pomace than in skins, while reverse results were observed in ACY. All samples lost significant amount of bioactive compounds during storage, in which ambient air and freeze dried samples had TPC reduction of 32-56% and 35-58%, respectively at the end of 16 weeks of storage. RSA in PN-P and M-P remained more than 50 mg TE/g d.m., meaning WGP still met the criteria of ADF definition after 16 weeks of storage. WGP extracts showed higher antibacterial efficiency against L. innocua than that of E. coli with MIC of 2, 7, 3 and 8% against L. innocua, and 3, 6, 4 and 9% against E. coli for PN-P, PN-S, M-P and M-S samples, respectively. This study demonstrated that Pinot Noir and Merlot pomace are good sources of ADF even after 16 weeks of storage at 15 °C and vacuum condition. Due to the highest antioxidant activity (RSA 37.46 mg AAE/g) and dietary fiber content (61%), PN-P was selected as ADF to be fortified in yogurt and salad dressing. Three types of WGP: whole powder (WP), liquid extract (LE) and freeze dried extract (FDE) with different concentrations were incorporated into yogurt (Y), Italian (I) and Thousand Island (T) salad dressings. TPC, RSA and dietary fiber content, major quality attributes including pH and peroxide value (PV) during the shelf life and consumer acceptance of fortified products were evaluated. The highest ADF were obtained in 3% WP-Y, 1% WP-I and 2% WP-T samples with the dietary fiber contents of 1.98%, 2.12% and 1.83% and RSA of 935.78, 585.60 and 706.67 mg AAE/kg, respectively. WP fortified products had more dietary fiber content than that of LE and FDE fortified ones because of the insoluble fractions. The pH dropped from 4.52 to 4.32 for 3% WP-Y during three weeks of storage at 4 °C, but remained stable in WGP-I and WGP-T samples after four weeks of storage at 4 °C. Adding WGP resulted in 35-65% reduction of PV in all samples compared to the control. In WGP-Y, the viscosity increased, but syneresis and lactic acid percentage were stable during storage. The 1%WP-Y, 0.5%WP-I and 1%WP-T samples were mostly liked by consumers. Study demonstrated that WGP can be used as a functional food ingredient for enhancing nutraceutical content and extending shelf-life of the food products. This study provided important information about the economically feasible drying methods for retaining the bioactive compounds in WGP during processing and storage and also suggested that WGP can be utilized as antioxidant dietary fiber to be fortified in consumer products to promote nutritional benefit and extend product shelf-life. / Graduation date: 2013

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