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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.
91

Contribution à l'amélioration de l'utilisation alimentaire du tourteau de canola : Décoloration par du peroxyde d'hydrogène et impact sur le produit

El Kadiri, Ihsane 18 April 2018 (has links)
La croissance constante de la population mondiale exige l’élaboration de stratégies alimentaires capables de soutenir les besoins nutritionnels des populations. Parmi les moyens stratégiques mis en œuvre, nous pouvons citer l'utilisation des sous-produits de transformation des aliments pour des besoins nutritionnels humains. En ce sens, l’industrie de concassage des graines oléagineuses, produisant des huiles végétales, fournit des résidus qui sont riches en fibres et en protéines. Ceci fait de ces résidus d’excellentes matières premières pour le développement de nouveaux ingrédients pour l'industrie alimentaire. Le tourteau de canola est un sous-produit du processus de broyage des graines de canola. En 2007 par exemple, la production du tourteau de canola au Canada était de l’ordre de 2050 tonnes métriques. Sur base sèche, le tourteau de canola contient environ de 12 à 20% (p / p) de fibres et de 35 à 45% (p / p) de protéines. Sa composition en acides aminés est bien équilibrée, ce qui rend du tourteau de canola une source potentielle de protéines pour l'alimentation humaine. Toutefois, des niveaux élevés de facteurs antinutritionnels comme les glucosinolates et les phytates ainsi que la présence de composés phénoliques limitent l’utilisation du tourteau de canola dans des produits alimentaires. Les composés phénoliques dans le tourteau de canola sont responsables de la couleur foncée, du goût amer et de l’odeur désagréable des matrices alimentaires dans lesquelles le tourteau est utilisé. Le niveau de composés phénoliques dans le tourteau de canola est plus élevé que celui dans le tourteau de soja, et il doit être diminué avant d’utiliser le tourteau de canola comme source d'ingrédients alimentaires. La couleur du tourteau doit également être considérablement améliorée. Jusqu'à présent, il n'existe aucune technologie complètement réussie pour diminuer la teneur en composés phénoliques dans le tourteau de canola et améliorer son odeur, sa couleur et son goût. Dans le présent travail, nous avons développé une nouvelle approche pour améliorer l'utilisation du tourteau de canola et de ses dérivés (protéines et fibres) comme ingrédients dans des applications alimentaires humaines. Pour ce faire, le tourteau de canola a été décoloré (blanchi) par des solutions de peroxyde d'hydrogène. La couleur du tourteau a été considérablement améliorée et elle est passée de L * = 45 à L * = 78. Le traitement au peroxyde d'hydrogène a permis aussi l'amélioration de l'extractabilité de la matière sèche totale dans les solutions aqueuses. Cette extractabilité était d'environ 22% pour le tourteau initial, tandis que celle du tourteau traité avec du peroxyde d'hydrogène est de 83%. La solubilité élevée de la matière sèche totale, comprenant les protéines et les fibres, permettra d'améliorer la biodisponibilité de ces ingrédients. La teneur en polyphénols totaux a été abaissée d'au moins 93%. Aussi, la matière extraite à sec a été caractérisée par de très bons paramètres organoleptiques (couleur, odeur et goût). Nous espérons que ce travail contribuera à résoudre des problèmes nutritionnels à l’échelle mondiale. / This research work was aimed to study the possibility of enhancing the use of canola meal as a source of food ingredients. The main objectives of this research work were to discolour the meal and to evaluate the product properties as well as the effect of the treatment on the extractability of the total dry matter, protein profile, total polyphenolics content, and overall acceptability of the end product. The constant growth of world population requires governments in all countries to develop food policies to support the nutritional needs of populations. Among the strategic means adopted, we can found the use of by-products of food processing practices for human nutritional needs. In this context, vegetable oils crushing industry provides residues which are rich in fibres and proteins. This makes them excellent raw materials for the development of new ingredients for the food industry. Canola meal is a by-product of de-oiling process of canola seeds. For example, the production of canola meal in Canada in 2007 was estimated at 2050 metric tonnes. On a dry basis, canola meal contains approximately 12-20% (w/w) carbohydrates and 35-45% (w/w) proteins. The well balanced and favourable amino acid composition of the canola meal makes this latter a potential source of proteins for human nutrition. However, high levels of antinutritional factors such as glucosinolates and phytates and the presence of phenolics prevent canola meal from being fully used in food products. Phenolics in canola meal are responsible of the dark color of the food matrices in which they are used, bitter taste, and strong undesirable smell. The level of phenolics compounds in canola meal is at least an order of magnitude higher than in soybean meal, and has to be decreased before the meal can be used as a source of food ingredients. The meal color must also be significantly improved. Enhancing the overall quality of the canola meal would contribute to both higher nutritional and monetary values of this material. Until now, there is no completely successful large scale technology for decreasing the phenolic content in canola meal and for improving its color, bitterness, and strong smell. The prupose of the present work was to develop a novel approach to improve the use of canola meal and its derivatives (proteins and fibres) as ingredients in food applications. The canola meal was successfully discolored (bleached) following a treatment with hydrogen peroxide solutions. The meal color was significantly improved and passed from L* = 45 up to L* = 78. The treatment with hydrogen peroxide allowed enhancing the extractability of the total dry matter in aqueous solutions. The initial meal extractability was approximately 22% whereas the meal treated with hydrogen peroxide was characterized by an extractability of the total dry matter of 83%. The increased solubility of the total dry matter, including proteins and fibres, will enhance the bioavailability of these ingredients. Total phenolic content was lowered by at least 93%. The extracted dry matter was characterized by very good organoleptic parameters (color, smell, and taste). The output of this research work will hopefully contribute to solving nutritional problems worldwide.
92

Utilization of canola seed fractions in ruminant feeds

Heendeniya Vidanaralalage, Ravindra Guptha 18 June 2008
Canola fibre-protein and can-sugar are the two by-products arising from a process for separating high quality protein fractions from canola meal. In the first trial chemical characteristics of fibre-protein and can-sugar were examined in comparison with commercial canola and soy meal. In the second trial in situ rumen degradability and kinetics of test feed was studied. Based on the findings of those two trials, available energy values were estimated based on NRC (2001) while protein contents potentially absorbable at small intestine were predicted using both NRC (2001) and DVE/OEB models. Subsequently a mixture of fibre-protein and can-sugar was used as an additive to dehydrated alfalfa pellet and two dairy cow trials were conducted to determine the palatability and examine effect on lactation performances of blended alfalfa pellet feeding in comparison with standard alfalfa pellet. Palatability difference was evaluated by Paterson -two choice alternating access method through a 7 day experimental period using 6 lactating Holstein cows. In the lactating performance trial, 6 cows were randomly assigned into two groups and two treatments were allocated over three experimental periods in a switchback design. <p>Can-sugar consisted of water soluble components (CP 15.6 %DM; SCP 96.2 %CP; NFC 99.9 %CHO) with non-protein nitrogen as the main CP fraction (NPN 96.2 %CP). Fibre-protein was a highly fibrous material (NDF: 55.6%; ADF: 46.3%; ADL: 24.1%) comparing to canola meal (NDF: 25.4%, ADF: 21.2%, ADL: 9.0%) due to presence of higher level of seed hulls in fibre-protein. Comparing to canola meal, fibre-protein contained 9% less CP and 1/4 of that consisted of undegradable ADIP. Rumen degradability of can-sugar was assumed as immediate and total as it was water soluble. Most of the ruminally undegradable nutrient components present in canola meal appeared to be concentrated into fibre protein during the manufacturing process and as a result fibre-protein has shown a consistently lower effective degradability of DM, OM, CP NDF and ADF comparing to both canola and soy meal. Available energy content in can-sugar was marginally higher than that of canola meal while fibre-protein contained only 2/3 that of canola meal. The predicted absorbable protein content at small intestine was about 1/2 that of canola meal. These results indicate that fibre-protein can be considered as a secondary source of protein in ruminant feed and a mixture of fibre-protein and can-sugar would nutritionally complement each other to formulate into a cheaper ingredient in ruminant ration. In the palatability study, there was no significant difference (P>0.05) in intake preference or finish time between the blended and standard alfalfa pellets. The results from the lactation study showed that there was no significant difference (P>0.05) in milk yield, dairy efficiency or milk composition between the blended and standard alfalfa pellets. The results from the two studies indicated that fibre-protein and can-sugar fractions could be used as an additive to alfalfa dehydrated pellet at 15% inclusion rate without compromising its palatability or the performance of dairy cows. <p>For future studies it is proposed to conduct feeding trials with varying levels of inclusions to alfalfa pellet to know the nutritional effect of fibre-protein and can-sugar while ascertain optimum inclusion rate.
93

Utilization of canola seed fractions in ruminant feeds

Heendeniya Vidanaralalage, Ravindra Guptha 18 June 2008 (has links)
Canola fibre-protein and can-sugar are the two by-products arising from a process for separating high quality protein fractions from canola meal. In the first trial chemical characteristics of fibre-protein and can-sugar were examined in comparison with commercial canola and soy meal. In the second trial in situ rumen degradability and kinetics of test feed was studied. Based on the findings of those two trials, available energy values were estimated based on NRC (2001) while protein contents potentially absorbable at small intestine were predicted using both NRC (2001) and DVE/OEB models. Subsequently a mixture of fibre-protein and can-sugar was used as an additive to dehydrated alfalfa pellet and two dairy cow trials were conducted to determine the palatability and examine effect on lactation performances of blended alfalfa pellet feeding in comparison with standard alfalfa pellet. Palatability difference was evaluated by Paterson -two choice alternating access method through a 7 day experimental period using 6 lactating Holstein cows. In the lactating performance trial, 6 cows were randomly assigned into two groups and two treatments were allocated over three experimental periods in a switchback design. <p>Can-sugar consisted of water soluble components (CP 15.6 %DM; SCP 96.2 %CP; NFC 99.9 %CHO) with non-protein nitrogen as the main CP fraction (NPN 96.2 %CP). Fibre-protein was a highly fibrous material (NDF: 55.6%; ADF: 46.3%; ADL: 24.1%) comparing to canola meal (NDF: 25.4%, ADF: 21.2%, ADL: 9.0%) due to presence of higher level of seed hulls in fibre-protein. Comparing to canola meal, fibre-protein contained 9% less CP and 1/4 of that consisted of undegradable ADIP. Rumen degradability of can-sugar was assumed as immediate and total as it was water soluble. Most of the ruminally undegradable nutrient components present in canola meal appeared to be concentrated into fibre protein during the manufacturing process and as a result fibre-protein has shown a consistently lower effective degradability of DM, OM, CP NDF and ADF comparing to both canola and soy meal. Available energy content in can-sugar was marginally higher than that of canola meal while fibre-protein contained only 2/3 that of canola meal. The predicted absorbable protein content at small intestine was about 1/2 that of canola meal. These results indicate that fibre-protein can be considered as a secondary source of protein in ruminant feed and a mixture of fibre-protein and can-sugar would nutritionally complement each other to formulate into a cheaper ingredient in ruminant ration. In the palatability study, there was no significant difference (P>0.05) in intake preference or finish time between the blended and standard alfalfa pellets. The results from the lactation study showed that there was no significant difference (P>0.05) in milk yield, dairy efficiency or milk composition between the blended and standard alfalfa pellets. The results from the two studies indicated that fibre-protein and can-sugar fractions could be used as an additive to alfalfa dehydrated pellet at 15% inclusion rate without compromising its palatability or the performance of dairy cows. <p>For future studies it is proposed to conduct feeding trials with varying levels of inclusions to alfalfa pellet to know the nutritional effect of fibre-protein and can-sugar while ascertain optimum inclusion rate.
94

Analyse du potentiel de production de biocarburants par la culture de canola (Brassica napus L.) sur les terres marginales du Québec et réduction des impacts liés à sa culture

Beaudette, Charles January 2010 (has links)
Le réchauffement global du climat serait attribuable majoritairement aux émissions de gaz à effet de serre dans l'atmosphère par les activités humaines comme la combustion des combustibles fossiles, la déforestation et les activités agricoles. Les biocarburants, des combustibles renouvelables et capables de mitiger les émissions de gaz à effet de serre, pourraient réduire notre dépendance aux combustibles fossiles et aider à la lutte contre les changements climatiques. De plus, l'implantation de systèmes de culture intercalaire (SCI) serait une alternative de choix permettant de revaloriser les terres marginales québécoises et restaurer une partie de leur fertilité originelle, ce qui permettrait de faire pousser les cultures de biocarburants sans faire compétition aux cultures nourricières déjà présentes sur les terres agricoles fertiles. Le présent travail s'inscrit donc au sein d'un réseau de chercheurs pan-canadien, le réseau des cultures vertes, afin de déterminer les rendements potentiels d'une culture de canola pour la production de biocarburants sur des terres marginales et d'évaluer l'impact de cette culture sur les émissions d'oxyde nitreux, un puissant gaz à effet de serre. Nous avons démontré au premier chapitre que la culture de biocarburants sur les terres marginales québécoises est possible avec l'implantation de systèmes de culture intercalaire, que ces systèmes peuvent mitiger les émissions d'oxyde nitreux des terres agricoles et que certains cultivars de canola performants peuvent aussi accroître les émissions d'oxyde nitreux. Dans le second chapitre, nous avons trouvé une tendance vers des rendements supérieurs et des besoins nutritionnels inférieurs pour les biocarburants de deuxième génération en comparaison avec ceux de la première génération et nous avons estimé que la substitution du tiers de notre consommation de combustibles fossiles serait réalisable avec 10 % des terres agricoles mondiales ainsi que les terres marginales par la production de biocarburants.
95

Drying Butanol Using Biosorbents in a Pressure Swing Adsorption Process

2016 February 1900 (has links)
A significant challenge in large scale industrial production of butanol is its low product titer. Butanol needs to be purified to higher than 99% purity in order to be used for fuel applications. The focus of this study is to selectively remove water from butanol-water vapor to achieve fuel grade butanol in a pressure swing adsorption (PSA) system using biosorbents developed from agricultural byproduct canola meal (CM). CM was characterized by Fourier Transform Infrared Spectroscopy (FTIR) that CM contains polar groups such as hydroxyls, carboxyls, and amines in cellulose, hemi-cellulose and protein that have the potential for water adsorption. Physico-chemical characterizations were also done to understand the major composition, elemental make-up, devolatilization characteristics and particle size distribution of the CM used. The results demonstrated that biosorbent based on CM was able to successfully dry lower grade butanol and generate fuel grade butanol of over 99 v/v%. Five operating parameters were studied at two different levels to get the optimum process conditions for butanol drying, including temperature (95 and 111°C); pressure (135 and 201 kPa); feed butanol concentration (55 and 95 v/v %); feed flow rate (1.5 and 3 mL min-1) and particle size of adsorbent (0.425-1.18 mm and 4.7 mm pellets). Orthogonal array design (OAD) tool was used to design experiments and to evaluate the effects of these parameters. The performance of butanol dehydration was evaluated using five indices - water uptake; butanol uptake; water selectivity; butanol recovery; and maximum effluent butanol concentration in the effluent. The results demonstrated that feed butanol concentration, temperature and pressure were found to be the most significant factors overall, affecting most of the indices. The effects of individual operating parameters on each butanol dehydration index were determined and a set of optimum operating conditions were proposed by the range analysis of the orthogonal array design at 111oC, 135 kPa, feed butanol concentration of 55 v/v%, feed butanol-water liquid flowrate of 3 mL/min and biosorbent particle size of 0.43-1.18 mm. The experiments conducted at the above mentioned optimum conditions resulted in water uptake of 0.48 g/g-ads, water selectivity of 5.4, butanol recovery of 90%, and the maximum butanol concentration in the effluent being over 99 v/v% , which are better than that obtained at any other conditions investigated in this work. The Dubinin–Polanyi model based on adsorption potential theory displayed a goodness of fit to the water adsorption isotherm data with a r2 value of 0.95 and average relative error of just 3.5%. The mean free energy determined from the model was 0.02 kJ/mol indicated the adsorption is physical. Thermodynamic parameters were also evaluated which revealed that the water adsorption is exothermic and spontaneous. Water saturated adsorbent was regenerated at 110°C under vacuum and reusability was studied. The contribution of two major components of CM namely cellulose and protein were also examined for their capability to selectively remove water from butanol. The results showed both of them were able to dry water, however cellulose was found to have a higher water uptake and water selectivity than protein, indicating that it plays a major role in drying butanol. In order to compare the performance of CM on drying of butanol with other biomaterials, adsorption experiments were done using corn meal as adsorbent, which is one of the most common starch based biosorbents for ethanol drying. The results demonstrated that canola meal had a higher water uptake and water selectivity than corn meal. Use of CM over corn meal adsorbent is also desirable so as to avoid placing pressure on food consumption. In addition, drying of butanol using other cellulose based biosorbents such as oat hull was also explored. Oat hull demonstrated a potential to adsorb water and dehydrate butanol, which requires further in-depth investigation.
96

Evaluating canola genotypes and harvest methods to reduce seedbank addition and longevity

2013 April 1900 (has links)
Seed loss in canola (Brassica napus, Brassica rapa and Brassica juncea) leads to considerable loss of revenue and dispersal of canola seeds into the soil seedbank. Once canola seeds enter the soil seedbank a portion can become secondarily dormant and persist for many years creating volunteer weed problems in following crops. Reducing canola seed loss and seedbank persistence can be an important strategy to reduce the incidence of volunteer weeds. The primary hypothesis of this research was that canola seedbank addition and dormancy induction in the seed are affected by genotype and harvest method. To test this hypothesis, three studies were conducted with the following objectives: i) to determine canola seedbank addition from windrowing and direct-harvesting operations on commercial farms in western Canada, ii) to determine agronomic- and harvest-related factors that may increase seed loss in canola, iii) to determine the effect of stage of crop maturity at harvest on potential to develop seed dormancy in canola, iv) to evaluate canola genotypes and harvest methods to reduce canola seedbank addition. A total of 66 canola fields were surveyed across Saskatchewan in 2010 and 2011. Shattered seeds from these fields were sampled within 3 weeks of harvest by using a vacuum cleaner. Agronomic- and harvest-related data were collected for each field using questionnaires. In a separate small plot study the effects of harvest methods (windrowing and direct-harvesting) and pod sealant products (Pod-Stik® and Pod Ceal DC®) on seed loss in five canola genotypes (InVigor5440, RR45H26, InVigor5020, RR4362, and CL8571) were evaluated in 2010 and 2011. In both years, 6 harvest samples were collected weekly from InVigor5440 and InVigor5020 genotypes starting at early stage of crop maturity until harvest to assess the effect of seed maturity on dormancy induction. On commercial farms, the average seedbank addition was 5,821 viable seeds m-2, which was equivalent to 7.3% of the total seed yield. There was no difference in the reported yield and seedbank addition between windrowed and direct-harvested canola on commercial farms. But in the small plot study, windrowing resulted in higher seedbank addition. Higher seedbank addition was observed when the yield of canola was higher and when producers had a larger area seeded to canola. The observed seedbank addition was also higher in Roundup Ready genotypes and when a conventional combine harvester was used to harvest canola. Little primary dormancy and low potential to secondary dormancy induction was observed in InVigor5440 and InVigor5020 seeds at an early stage of crop maturity. But at full maturity seeds of both genotypes had no primary dormancy but showed high potential for secondary dormancy induction. This indicates that windrowing the evaluated genotypes at early stage of crop maturity lowered the potential for secondary dormancy induction. There were appreciable differences in seedbank addition among the evaluated canola genotypes but pod sealant products did not affect seed yield and seed shatter in canola. The results of this study suggest that canola seedbank addition can be minimized by growing genotypes having reduced seed loss and with the adoption of direct-harvesting operations.
97

Efecto de la adición de extractos de hojas de olivo o palto en la estabilidad termooxidativa de aceites de diferente insaturación

Jiménez Patiño, Paula Andrea January 2010 (has links)
Tesis presentada como parte de los requisitos para optar al Grado de Doctor en Nutrición y Alimentos / Programa Conjunto: Facultad de Ciencias Agronómicas, Facultad de Ciencias Químicas y Farmacéuticas, Facultad de Medicina, Facultad de Ciencias Veterinarias y Pecuarias e Instituto de Nutrición y Tecnología de Alimentos. / Las materias grasas sometidas a proceso de fritura en profundidad (180 ºC), sufren deterioro oxidativo, hidrolítico y térmico, produciendo una serie de nuevos compuestos volátiles y no volátiles. Estos últimos pueden alterar las propiedades organolépticas y nutricionales del alimento, así como también pueden afectar la salud de los consumidores. Para retardar el deterioro oxidativo se ha recurrido a distintos mecanismos, siendo el uso de antioxidantes la herramienta más ampliamente utilizada por la industria de los alimentos. Una fuente importante de antioxidantes naturales son los extractos vegetales, que pueden obtenerse desde distintas partes de las plantas. De acuerdo a estos antecedentes, en este trabajo se caracterizaron ocho tipos de extractos obtenidos de hojas de olivo (Olea europaea) o palto (Persea americana) por cuatro métodos de extracción diferentes: hidroalcohólico (HAO o HAP), jugo (JO o JP), supercrítico-CO2 (EFSO o EFSP) y oleorresina (OO o OP), mediante su contenido de polifenoles totales por Folin-Ciocalteu, identificación de polifenoles por LC-MS y capacidad antioxidante por DPPH. Se estudió el efecto de la adición de los extractos de hojas de olivo y palto (hidroalcohólicos, jugos y supercrítico-CO2) en dos concentraciones (250 y 630 mg EAC/Kg aceite) sobre la estabilidad oxidativa (tiempo de inducción) de aceites de distinto grado de insaturación (soja, canola y girasol alto oleico). Además, se estudió el efecto de la adición de extracto hidroalcohólico de hojas de olivo o palto (600 mg EAC/Kg aceite) a aceite de canola y girasol alto oleico sometidos a fritura de papas “french”, evaluando la formación de compuestos polares y la degradación de tocoles. Los resultados mostraron que los diferentes extractos de hojas de olivo y palto presentaron distinta composición en polifenoles, lo que sugiere que el método de extracción y el pretratamiento de las hojas (escaldado, secado, molienda, entre otros) determinan el perfil de polifenoles. Siendo los extractos hidroalcohólicos de hojas de olivo y palto, los que presentaron los mayores contenidos de polifenoles totales y capacidad antioxidante. El estudio de la estabilidad oxidativa por Rancimat mostró que HAO, EFSO y EFSP (630 mg EAC/Kg aceite) poseen un efecto antioxidante, aumentando el tiempo de inducción de los tres aceites estudiados con respecto al control (p< 0,05), aunque el mayor efecto lo presentaron los aceites más monoinsaturados. Por otro lado, con JO se observó un comportamiento pro-oxidante en los tres aceites estudiados. El HAO adicionado a los aceites de girasol alto oleico o canola (600 mg EAC/Kg aceite) durante la fritura de papas “french” disminuyó la formación de compuestos polares con respecto al control (p<0,05) y mostró un efecto antipolimerizante en ambos aceites. Por otro lado, se observó un aumento en la permanencia de los tocoferoles cuando se adicionó HAO o HAP a estos aceites con respecto al control, lo que sugiere que los tocoferoles son regenerados por los polifenoles u otros componentes menores presentes en los extractos. En consecuencia, los extractos hidroalcohólicos de hojas de olivo y palto (árboles de importancia productiva y comercial en nuestro país por sus respectivos frutos), se pueden considerar como nuevas fuentes de compuestos antioxidantes naturales, ricos en polifenoles, capaces de actuar sinérgicamente con los sistemas antioxidantes propios de los aceites de canola y girasol alto oleico. Este efecto es mayor con el extracto hidroalcohólico de olivo (p<0,05), aumentando así la estabilidad y mejorando el perfil de ambos aceites, lo que representa ventajas desde un punto de vista nutricional, tecnológico y comercial. / Fats and oils deteriorate through oxidative, hydrolytic and thermal reactions when submitted to deep frying processes (180 ºC), producing new volatile and not volatile compounds. These compounds alter the organoleptic and nutritional properties of the food and may be deleterious to the consumer. To delay the oxidative deterioration of oils different mechanisms have been used in the food industry, mainly the incorporation of antioxidants. Plant extracts are important sources of natural antioxidants, which can be obtained from different parts of the plants. Although to identify the individual properties of each component in the extract is complex, the global behaviour may be determined without the need of isolating each particular component. Eight extracts from olive and avocado leaves were obtained by four different extraction methods: hydroalcoholic (HAO or HAP), juice (JO or JP), supercritical-CO2 (EFSO or EFSP) and oleoresin (OO or OP), which were characterized by the total polyphenols content (Folin- Ciocalteu method), phenol chromatographic profiles (LC-MS) and antioxidant activity (DPPH). The effect of the addition of olive and avocado leaves extracts (hydroalcoholic, juice and supercritical-CO2) on the oxidative stability of vegetables oils with different unsaturation (soybean oil, canola oil and high oleic sunflower oil) was studied at two concentrations (250 and 630 mg CAE/Kg oil). Besides, French potatoes were submitted to frying using canola and high oleic sunflower oils added to hydroalcoholic olive or avocado leaves extracts (600 mg EAC/Kg oil), studying the polar compounds formation and tocols degradation. The results indicate that the olive and avocado hydroalcoholic extracts showed the highest total polyphenols content and antioxidant capacity. The phenolic composition differ among different extracts, showing the effect of the extraction method; solvent polarity and leaves pre-treatment (i.e. dried, scalded and grinded). The oxidative stability study (using Rancimat ®) showed that the addition of 630 mg CAE/Kg oil of HAO, EFSO and EFSP had an antioxidant effect on the oil systems studied, increasing significatively the induction time (p<0.05). This effect was higher when the system was more monounsaturated. Contrary, a pro-oxidant behavior was observed in JO for oil systems studied. French potato fries in high oleic sunflower and canola oils added with HAO (600 mg EAC/Kg oil) reduced the formation of polar compounds with respect to control (p<0.05) and showed an antipolymeric effect on both oils. On the other side, an increase in the retention of tocopherol was observed when HAO or HAP was added to these oils with respect to control, suggesting regeneration of tocopherol by the polyphenols of the extracts and the extent depends on polyphenols structural features. Therefore, the hydroalcoholic extracts of olive and avocado leaves (trees of both commercial and productive importance in Chile) can be considered as new sources of natural antioxidant compounds. These extracts showed a high polyphenol content and may act synergistically with the antioxidant systems of canola and high oleic sunflower oils. This effect is significantly higher in the hydroalcoholic extract of olive leaves, increasing the stability and improving the oil`s profile in the nutritional, technological and commercial point of view. / Mecesup
98

Polinizadores de canola : perspectivas para o manejo sustent?vel de insetos, produtividade de gr?os e mudan?as clim?ticas / Canola pollinators : perspectives for sustainable use of insects, yield and climatic changes

Oliveira, Rosana Halinski de 20 March 2017 (has links)
Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-10-02T14:26:17Z No. of bitstreams: 1 TES_ROSANA_HALINSKI_DE_OLIVEIRA_COMPLETO.pdf: 1515461 bytes, checksum: a0570fb682b073eeb04b28c31001af16 (MD5) / Made available in DSpace on 2017-10-02T14:26:17Z (GMT). No. of bitstreams: 1 TES_ROSANA_HALINSKI_DE_OLIVEIRA_COMPLETO.pdf: 1515461 bytes, checksum: a0570fb682b073eeb04b28c31001af16 (MD5) Previous issue date: 2017-03-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The current loss of biodiversity has negative consequences for the environment and impacts several pollination ecossystem services, from which human society benefits directly or indirectly. Among the main pollinators bees, wasps, coleopterans, flies and butterflies stand out. Bees pollinate more than 90% of 107 worldwide crops and other insects might contribute with 20-50% of pollination. Studies about canola (Brassica napus L. cultivar ?ole?fera?) point out that insect visitation promotes an increase of 12 to 47% in grain productivity. Faced with this, the present work aimed to know the bee, wasp and coleopteran diversity in the canola agroecossystem and identify potential pollinators of the crop. Furthermore, it was evaluated how the landscape and the pollinators influence in the productivity of canola, as well as the habitat suitability for the pollinator species in the face of climatic change in future scenarios (2050). Insects were collected with pan traps in eight fields of B. napus (Hyola 420 and Hyola 61) in the towns of Esmeralda, Estrela and Guarani das Miss?es, RS, Brazil. For the development of the habitat suitability maps it was used the occurrence records of species in databases and of the canola fields in the towns informed by the crop promoters. Among the wasps the social species Brachygastra lecheguana and Protonectarina sylveirae and the solitary species Campsomeris spp. stand out as potential pollinators. The most representative families of coleopterans were Melyridae, Curculionidae, Nitidulidae, Chrysomelidae and Scarabaeidae, and the most abundant species, which is is polliniferous, with a pubescent body and dense bristles, to which the pollen grains adhere and are transported, thus probably it is a pollinator of canola and surrounding flowers. The productivity of canola was positively influenced by the diversity of social and solitary bees, and the distance from the forest fragment affected the composition of bee guilds present inside the canola fields. It was observed that the semi-natural areas presented a positive correlation with the social native bee species richness. Regarding the category of landscape named ?Forest?, it was observed that there is a negative correlation in the 1000 meters radius with the subsocial or solitary bee abundance, possibly explained by their nesting habit, which is mainly underground, which means that it is not exclusively dependent of forest to build their nests. Accordingly, in the ?Agriculture? category, the agricultural landscape in the 1000 meters radius was positively correlated to the abundance of the same guild, fact attributed to the nesting inside canola fields. In view of the different degrees of heterogeneity of the landscape in canola crops, it can be observed that the composition of insects in the canola agroecossystem responds to the ecological and historical factors of each region, being related to the quality of the habitat and food resources for the species. The areas of habitat suitability for canola show a high potential for future crop expansion, however, for this to happen, strategies such as the use of cultivars that have greater tolerance to climatic variables should be established, because they affect plant phenology. In addition, it is suggested to use efforts to introduce the crops in places that are suitable in the future scenario. Furthermore, when comparing the habitat suitability only for canola and then in overlapping with the stingless bee species, we can observe that the appropriate areas increase significantly, reinforcing that for the expansion of the crop, conservation measures of natural and semi-natural habitats for providing food and nesting resources for pollinators are needed. / A perda atual da biodiversidade tem consequ?ncias negativas para o meio ambiente e impacta diversos servi?os ecossist?micos de poliniza??o, dos quais a sociedade humana se beneficia direta ou indiretamente. Entre os principais polinizadores destacam-se as abelhas, vespas, cole?pteros, moscas e borboletas. Sabe-se que as abelhas polinizam mais de 90% de 107 culturas globais e que outros insetos podem contribuir com 25-50% na poliniza??o. Estudos sobre canola (Brassica napus L. variedade ole?fera) apontam que a visita de insetos promove o aumento da produtividade dos gr?os de 12 a 47%. Diante disto, o presente trabalho objetivou conhecer a diversidade de abelhas, vespas e cole?pteros em agroecossistema de canola e identificar potenciais polinizadores da cultura. Al?m disso, foi avaliado como a paisagem e os polinizadores influenciam na produtividade de canola, bem como as ?reas de adequabilidade de habitat para esp?cies polinizadoras frente ?s mudan?as clim?ticas em cen?rios futuros (2050). Os insetos foram coletados com o uso de pan traps em oito lavouras de B. napus (Hyola 420 e Hyola 61) nos munic?pios de Esmeralda, Estrela e Guarani das Miss?es, RS, Brasil. Para desenvolvimento dos mapas de adequabilidade de habitat utilizou-se registros de ocorr?ncias das esp?cies em bases de dados e dos munic?pios com lavouras de canola fornecidos por fomentadoras da cultura. Dentre as vespas destacam-se as esp?cies sociais Brachygastra lecheguana e Protonectarina sylveirae e as esp?cies solit?rias Campsomeris spp., Eucyrtothynnus spp. e Tiphia spp. como potenciais polinizadores. As fam?lias mais representativas de cole?pteros foram Melyridae, Curculionidae, Nitidulidae, Chrysomelidae e Scarabaeidae, sendo que a esp?cie mais abundante, Astylus variegatus, que ? polin?faga, com corpo pubescente e densas cerdas, aos quais os gr?os de p?len se aderem e s?o transportados, portanto, provavelmente ? polinizador da canola e de flores do entorno. A produtividade de canola foi positivamente influenciada pela diversidade de abelhas, sociais e solit?rias, e a dist?ncia do remanescente florestal afetou a composi??o das guildas de abelhas presentes no interior da lavoura. Foi observado que as ?reas seminaturais tiveram correla??o positiva com a riqueza de abelhas sociais nativas. J? na categoria de paisagem denominada ?Mata?, pode-se observar que h? correla??o negativa no raio de 1000 metros com a abund?ncia de abelhas subsociais ou solit?rias, possivelmente atribu?do ao h?bito de nidifica??o destas, que ? predominantemente subterr?neo, isto ?, n?o dependem exclusivamente de florestas para construir seus ninhos. Em conson?ncia, na categoria de ?Agricultura?, a paisagem agr?cola no raio de 1000 metros foi correlacionada positivamente com a abund?ncia da mesma guilda, fato atribu?do a nidifica??o no interior das lavouras. Diante de diferentes graus de heterogeneidade da paisagem nas lavouras de canola pode-se observar que a composi??o de insetos no agroecossistema da canola responde aos fatores ecol?gicos e hist?ricos de cada regi?o, relacionando-se com a qualidade do habitat e recursos alimentares para as esp?cies. As ?reas de adequabilidade de habitat para canola mostram um elevado potencial para expans?o da cultura no futuro, contudo para que isto aconte?a deve-se estabelecer estrat?gias como a utiliza??o de cultivares que tenham maior toler?ncia ?s vari?veis clim?ticas, visto que estas afetam a fenologia das plantas. Em acr?scimo, sugere-se empregar esfor?os para introdu??o da cultura em lugares que s?o adequados no cen?rio futuro. Al?m disso, ao compararmos a adequabilidade de habitat somente para canola e depois em sobreposi??o com as esp?cies de abelhas sem ferr?o, podemos observar que as ?reas adequadas aumentam expressivamente, refor?ando que para expans?o da cultura necessita-se medidas de conserva??o de habitats naturais e seminaturais para fornecer recursos alimentares e de nidifica??o para os polinizadores.
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Optimización del proceso de acidólisis enzimática en dióxido de carbono supercrítico de aceite de canola (Brassica napus L.) con concentrado de ácidos grasos poliinsaturados de cadena larga

Cedano Romero, José Manuel January 2015 (has links)
Tesis presentada para optar al grado de Magíster en Alimentos mención Gestión, Calidad e Inocuidad de los Alimentos / Los ácidos grasos poliinsaturados de cadena larga (AGPICL) omega-3 (n-3) han obtenido una creciente atención debido a su papel beneficioso en la nutrición y salud humana. Los triacilglicéridos estructurados (TAGs) son aquellos que han modificado su composición y/o distribución posicional de los ácidos grasos en la molécula de glicerol, mediante métodos químicos y/o enzimáticos, obteniendo de este modo una mejora de sus propiedades funcionales y/o nutricionales. En este sentido, la transesterificación enzimática proporciona varias ventajas, como el uso de temperaturas relativamente bajas y una mayor selectividad del catalizador. En los últimos años, la tecnología de fluidos supercríticos, ha demostrado proporcionar una posibilidad ventajosa en el proceso de catálisis enzimática debido a su alta versatilidad e inocuidad. El objetivo del presente estudio fue optimizar las variables del proceso de acidólisis enzimática de aceite de canola (Brassica napus L.) con concentrado AGPICL para obtener triacilglicéridos estructurados con una baja relación de ácidos grasos n-6/n-3. Para ello, se empleó lipasa B inespecífica de Candida antarctica inmovilizada en condiciones CO2 supercrítico. El aceite crudo de salmón obtenido a partir de los subproductos industriales se utilizó para obtener concentrados de ácidos grasos poliinsaturados de cadena larga (AGPICL). Como primer paso, se caracterizó mediante análisis físico-químicos el aceite de canola y por cromatografía de gas líquido para obtener sus perfiles de ácidos grasos. Luego se obtuvo un concentrado AGPICL a partir de aceite crudo de salmón mediante hidrólisis básica y posterior complejación con urea. Posteriormente se optimizaron las variables del proceso de acidólisis enzimática mediante un diseño compuesto central rotacional 25-1 más estrella, de 5 factores con 30 ensayos experimentales, basado en la Metodología de Superficie Respuesta. Las condiciones óptimas que minimizaron la relación AG n-6/n-3 a un valor de 1,16 para los TAGs purificados correspondieron a un relación AGPICL/Canola de 70,6%, temperatura de 57,0 ºC, presión de 178,0 bar, tiempo de 19,6 h y concentración de enzima de 8,0% / Long-chain n-3 polyunsaturated fatty acids (PUFA) have attracted an increasing attention due to their beneficial role on human health and nutrition. Structured triacylglycerols (TAGs) are molecules that have modified their composition and/or spatial distribution of fatty acids in the glycerol structure through chemical and/or enzymatic methods, thus obtaining an enhancement of their functional and nutritional properties. In this sense, enzymatic transesterification provides several advantages such as the employment of low temperatures and greater catalyst selectivity. In recent years, supercritical fluids technology has shown to provide an advantageous possibility in the enzymatic catalyzation process due to its versatility and safety. The objective of the present study was to optimize the process variables of enzymatic acidolysis of PUFA-enriched canola (Brassica napus L.) oil to obtain structured TAGs with a low n-6/n-3 fatty acids ratio. In order to achieve this objective, unspecific lipase B from immobilized Candida Antarctica was employed under supercritical-CO2 conditions. Salmon oil obtained from industrial by-products was utilized to obtain the starting PUFA source. As a first step, oils from canola and salmon were analysed by physico-chemical quality parameters (lipid hydrolysis degree and content on primary and secondary lipid oxidation compounds) and by gas-liquid chromatography to obtain their fatty acids profiles. A PUFA concentrate was obtained from salmon oil by basic hydrolysis and further urea complexation. Then, the process variables of enzymatic acidolysis were optimized by means of a composite-central design of 25-1 + star, with five factors and 30 experimental runs, based on the response-surface methodology (RSM). Optimal conditions that minimized the relationship AG n- 6/n-3 to a 1.16 score for the purified TAGs corresponded to a LCPUFA/canola ratio of 70.6%, temperature of 57.0 ° C, pressure of 178.0 bar, time of 19.6 h and enzyme concentration of 8.0% / Fondecyt / 31/12/2018
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The loss of grain freshness : indicators or storage induced quality loss in dry barley and canola grain

Reuss, Rainer, n/a January 1999 (has links)
The work presented here explores the effect of storage on chemical and other characteristics of dry, free of added chemicals and pest-free barley and canola grain. This was achieved by measuring the changes in a number of variables of grain stored at different temperatures under laboratory conditions and in commercial storage. The following measurements were carried out: Viability, moisture contents (mc), oil contents (oc), whole grain colour, spectrophotometry of grain extracts, hydroxy methyl furaldehyde (HMF), changes in storage atmospheres, organic sulphide levels, tocol concentrations (vitamin E), Iodine Value (IV), Thiocyanogen Value (TV), Peroxide Value (PV), p-Anisidine Value (p-AV) and Acid Value (AV). The mc of canola and barley were within the range considered safe for storage. Oil content of canola did not change significantly with storage. Viability of canola stored at 4 and 25 °C did not change noticeably, but higher storage temperatures resulted in seed death. Barley maintained high viabilities at low temperatures, but was more susceptible to high temperatures than canola. Colour changes of whole barley grain in storage were pronounced and temperature dependent. Colorimetry of whole barley grain showed potential as a tool for monitoring quality changes in storage. Absorption spectra of grain extracts reflected chemical and physiological changes in storage. HMF, an indicator of Maillard browning, accumulated in short to medium term storage at 45°C and in long term storage at 25 and 35°C. Measurement of HMF was considered useful for monitoring quality changes of stored cereal grain. In a study of storage atmospheres, changes in the concentrations of carbon dioxide, carbon monoxide, oxygen, carbon disulphide and carbonyl sulphide were shown to be useful indicators of quality loss of grain in storage. Gas concentrations usually depended on storage temperature and time and reflected the storage history of the commodity. They indicated loss of carbohydrates and lipids by respiration, oxidative damage and deterioration of sulphur containing amino acids and other compounds. Oil quality indicators were consistent with oxidative damage to canola lipids in storage. IV, TV, and p-AV of canola oil did not correlate with quality of commercial samples. However, a relationship between increases in PV and high storage temperatures in canola was shown and AV increased in storage dependent on storage temperature and time. In barley and canola, the concentration of anti-oxidant tocol species (vitamin E) decreased at 35 and 45°C storage dependent on storage time. The overall tocol content as well as vitamin E activity decreased with storage decreasing the nutritional value of the commodities and indicating oxidative damage to lipids. It was concluded that the storage of dry, pest-free whole barley and canola grain at moderate temperatures (25-45°C) resulted in chemical and other changes. The consequence of these changes was a measurable reduction in the freshness of grain relevant to the nutritional, food technological and commercial quality of grain.

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