971 resultados para Olive oil mills
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The present study aims at the use of Raman spectroscopy in the quantification of unsaturated fats in fat-containing foods, compared to the information available in the Nutritional Table, to obtain a non-destructive optical quantification of unsaturation. Raman spectra of edible oil, margarine, mayonnaise, hydrogenated fat, and butter were obtained with a near-infrared Raman spectrometer (830nm). By analyzing selected bands in the regions of 1750, 1660, 1440, 1300, and 1260cm-1, the amount of total and unsaturated fat of samples of oil, margarine, and mayonnaise were correlated with the information displayed in the Nutritional Table. The amount of unsaturated trans fat in selected samples was correlated to the Raman shift of 1660cm-1. Dispersive Raman spectroscopy was shown to be effective in quantifying the unsaturated fats in oil, margarine, and mayonnaise, and trans fat in hydrogenated oils and butter.
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The effects of type of grain (wheat vs. sorghum) and oil supplement/kg diet [0, 20g olive oil (OL), 20g safflower oil (SO), 10 g OL plus 10 g SO (OLSO)], over a 12-week period on the performance, plasma and lipoproteins lipids [cholesterol (C), triglycerides (TG), phospholipid (P)], and yolk C and fatty acids concentrations of laying hens were studied. Hens fed on the sorghum diet had significantly (P
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Background Over the years, food industry wastes have been the focus of a growing interest due to their content in high added-value compounds. A good example are the olive oil by-products (OOBP), which retain a great amount of phenolic compounds during olive oil production. Their structure and biological properties justify their potential use as antioxidants in other food products. The efficient recovery of phenolic compounds has been extensively studied and optimized in order to maximize their reintroduction in the food chain and contribute to a higher valorization and better management of wastes from olive oil industry. Scope and approach This paper reviews the most representative phenolic compounds described in OOBP and their biological properties. New extraction procedures to efficiently recover these compounds and the most advanced chromatographic techniques that have been used for a better understanding of the phenolic profile of these complex matrices are also referred. Finally, this paper reports the main applications of OOBP, with emphasis on their phenolic content as natural antioxidants for food applications. Key findings and conclusions Besides their antioxidant activity, phenolic compounds from OOBP have also shown antimicrobial and antitumoral properties. Their application as food antioxidants requires new extraction techniques, including the use of non-toxic solvents and, in a pilot scale, the use of filters and adsorbent resins. The inclusion of phenolic compounds from OOBP in some food matrices have improved not only their antioxidant capacity but also their sensory attributes.
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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics
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Different oil-containing substrates, namely, used cooking oil (UCO), fatty acids-byproduct from biodiesel production (FAB) and olive oil deodorizer distillate (OODD) were tested as inexpensive carbon sources for the production of polyhydroxyalkanoates (PHA) using twelve bacterial strains, in batch experiments. The OODD and FAB were exploited for the first time as alternative substrates for PHA production. Among the tested bacterial strains, Cupriavidus necator and Pseudomonas resinovorans exhibited the most promising results, producing poly-3-hydroxybutyrate, P(3HB), form UCO and OODD and mcl-PHA mainly composed of 3-hydroxyoctanoate (3HO) and 3-hydroxydecanoate (3HD) monomers from OODD, respectively. Afterwards, these bacterial strains were cultivated in bioreactor. C. necator were cultivated in bioreactor using UCO as carbon source. Different feeding strategies were tested for the bioreactor cultivation of C. necator, namely, batch, exponential feeding and DO-stat mode. The highest overall PHA productivity (12.6±0.78 g L-1 day-1) was obtained using DO-stat mode. Apparently, the different feeding regimes had no impact on polymer thermal properties. However, differences in polymer‟s molecular mass distribution were observed. C. necator was also tested in batch and fed-batch modes using a different type of oil-containing substrate, extracted from spent coffee grounds (SCG) by super critical carbon dioxide (sc-CO2). Under fed-batch mode (DO-stat), the overall PHA productivity were 4.7 g L-1 day-1 with a storage yield of 0.77 g g-1. Results showed that SCG can be a bioresource for production of PHA with interesting properties. Furthermore, P. resinovorans was cultivated using OODD as substrate in bioreactor under fed-batch mode (pulse feeding regime). The polymer was highly amorphous, as shown by its low crystallinity of 6±0.2%, with low melting and glass transition temperatures of 36±1.2 and -16±0.8 ºC, respectively. Due to its sticky behavior at room temperature, adhesiveness and mechanical properties were also studied. Its shear bond strength for wood (67±9.4 kPa) and glass (65±7.3 kPa) suggests it may be used for the development of biobased glues. Bioreactor operation and monitoring with oil-containing substrates is very challenging, since this substrate is water immiscible. Thus, near-infrared spectroscopy (NIR) was implemented for online monitoring of the C. necator cultivation with UCO, using a transflectance probe. Partial least squares (PLS) regression was applied to relate NIR spectra with biomass, UCO and PHA concentrations in the broth. The NIR predictions were compared with values obtained by offline reference methods. Prediction errors to these parameters were 1.18 g L-1, 2.37 g L-1 and 1.58 g L-1 for biomass, UCO and PHA, respectively, which indicates the suitability of the NIR spectroscopy method for online monitoring and as a method to assist bioreactor control. UCO and OODD are low cost substrates with potential to be used in PHA batch and fed-batch production. The use of NIR in this bioprocess also opened an opportunity for optimization and control of PHA production process.
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Olive oils may be commercialized as intense, medium or light, according to the intensity perception of fruitiness, bitterness and pungency attributes, assessed by a sensory panel. In this work, the capability of an electronic tongue to correctly classify olive oils according to the sensory intensity perception levels was evaluated. Cross-sensitivity and non-specific lipid polymeric membranes were used as sensors. The sensor device was firstly tested using quinine monohydrochloride standard solutions. Mean sensitivities of 14±2 to 25±6 mV/decade, depending on the type of plasticizer used in the lipid membranes, were obtained showing the device capability for evaluating bitterness. Then, linear discriminant models based on sub-sets of sensors, selected by a meta-heuristic simulated annealing algorithm, were established enabling to correctly classify 91% of olive oils according to their intensity sensory grade (leave-one-out cross-validation procedure). This capability was further evaluated using a repeated K-fold cross-validation procedure, showing that the electronic tongue allowed an average correct classification of 80% of the olive oils used for internal-validation. So, the electronic tongue can be seen as a taste sensor, allowing differentiating olive oils with different sensory intensities, and could be used as a preliminary, complementary and practical tool for panelists during olive oil sensory analysis.
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Dissertação de mestrado em Bioengenharia
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Chicken is the most widely consumed meat all over the world due to chickens being easy to rear, their fast growth rate and the meat having good nutritional characteristics. The main objective of this paper was to study the effects of dietary fatty by-products in low, medium and high levels of oxidized lipids and trans fatty acids (TFAs) on the contents of cholesterol and oxycholesterols in meat, liver, and plasma of chickens. A palm fatty acid distillate, before and after hydrogenation, and a sunflower-olive oil blend (70/30, v/v) before and after use in a commercial frying process were used in feeding trials after adding 6% of the fats to the feeds. Highly oxidized lipid and TFA feeds significantly increased the contents of cholesterol and oxycholesterols in all tissues of chicken (0.01 < p <= 0.05). The contents of oxycholesterols in chicken meat, liver and plasma obtained from TFA feeding trials varied between 17 and 48 μg/100 g in meat, 19-42 μg/100 g in liver and 105-126 μg/dL in plasma. In contrast, in the oxidized lipid feeding trials, oxycholesterols varied between 13 and 75 μg/100 g in meat, 30-58 μg/100 g in liver and 66-209 μg/dL in plasma. Meat from chickens fed with feeds containing high levels of TFAs or oxidized lipids may contribute to higher ingestion of cholesterol and oxycholesterols by humans.
Sustainability of palm oil production and opportunities for Finnish technology and know-how transfer
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The global demand for palm oil is growing, thus prompting an increase in the global production particularly in Malaysia and Indonesia. Such increasing demand for palm oil is due to palm oil’s relatively cheap price and versatile advantage both in edible and non-edible applications. Along with the increasing demand for palm oil, particularly for the production of biofuel, is a heated debate on its sustainability. Ecological degradation, climate change and social issues are among the main sustainability issues pressing the whole palm oil industry today. Clean Development Mechanism (CDM) projects fulfilling the imperatives of the Kyoto Protocol are starting to gain momentum in Malaysia as reflected by the increasing registration of CDM projects in the palm oil mills. Most CDM projects in palm oil mills are on waste-to-energy, cocomposting, and methane recovery with the latter being the most common. The study on greenhouse gases (GHG) in the milling process points that biogas collection and energy utilisation has the greatest positive effect on GHG balance. On the other hand, empty fruit bunches (EFB) end-use as energy and high energy efficiency of the mill have the least effect on GHG balance of the mill. The range of direct GHG emissions from the palm oil mill is from 2.5 to 27 gCO2e/MJCPO, while the range of GHG emissions with all indirect and avoided emissions included is from -9 to 29 gCO2e/MJCPO. Comparing this GHG balance result with that of the EU RES-Directive suggests a further check on the values and emissions consideration of the latter.
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One hypothesis for the increased incidence of atopic diseases has been that it is associated with changing dietary habits, especially the changed intake of essential fatty acids (EFAs). The metabolism of EFAs produces eiconasoids, prostaglandins and leukotrienes, which are essential to organs and play a major role in regulation of inflammation and immune response. In some studies persons with atopic dermatitis have been found to have reduced levels of EFAs. The first year of infancy as well as the foetal period are crucial for the development of atopic immune response. The composition of blackcurrant seed oil (BCSO) corresponds to the recommended ratio of EFAs n-3 and n-6 in the diet (1/3-1/4) and as a dietary supplement could, even in small doses, modify the unbalance of EFAs in an efficient way. The purpose of this study was to find out whether atopic allergies can be prevented by supplementing the diet of pregnant mothers with blackcurrant seed oil and whether it could affect the immunological balance of a child. We also sought to find out whether a blackcurrant seed oil supplementation can affect the composition of breast milk to suppress the T helper 2 lymphocyte (Th2) responses in infants. 313 pregnant mothers were randomly assigned to receive BCSO (n=151) or olive oil as placebo (n=162). Supplementation was started at the 8th to 16th weeks of pregnancy, 6 capsules per day (dose of 3 g), and continued until the cessation of breastfeeding. It was thereafter followed by direct supplementation to infants of 1 ml (1 g) of oil per day until the age of two years. Atopic dermatitis and its severity (SCORAD index) were evaluated, serum total IgE was measured and skin prick tests were performed at the age of 3, 12 and 24 months. Peripheral blood mononuclear cell (PBMC) samples were taken at the age of 3 and 12 months and breast milk samples were collected during the first 3 months of breastfeeding. Parental atopy was common (81.7%) in the studied infants, making them infants with increased atopy risk. There was a significantly lower prevalence of atopic dermatitis in the BCSO group (33%) than in the olive oil group (47%) at the age of 12 months. Also, SCORAD was lower in the BCSO group than in the olive oil group. Dietary intervention with BCSO had immunomodulatory effects on breast milk, inducing cytokine production from Th2 to Th1 immunodeviation. It decreased the level of IL-4 and elevated the level of IFN-γ. BCSO intervention did not affect cytokines in the children’s PBMC. However, children of smoking parents in the combined BCSO and olive oil group had significantly elevated levels of Th2 type cytokines IL-4, IL-5 and the proinflammator cytokine TNF. Dietary supplementation with BCSO is safe. It is well tolerated and transiently reduces the prevalence of atopic dermatitis at the age of 12 months. It can possibly become a potential tool in prevention of atopic symptoms when used at the early stages of life.
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Poor cold flow properties of vegetable oils are a major problem preventing the usage of many abundantly available vegetable oils as base stocks for industrial lubricants. The major objective of this research is to improve the cold flow properties of vegetable oils by various techniques like additive addition and different chemical modification processes. Conventional procedure for determining pour point is ASTM D97 method. ASTM D97 method is time consuming and reproducibility of pour point temperatures is poor between laboratories. Differential Scanning Calorimetry (DSC) is a fast, accurate and reproducible method to analyze the thermal activities during cooling/heating of oil. In this work coconut oil has been chosen as representative vegetable oil for the analysis and improvement cold flow properties since it is abundantly available in the tropics and has a very high pour point of 24 °C. DSC is used for the analysis of unmodified and modified vegetable oil. The modified oils (with acceptable pour points) were then subjected to different tests for the valuation of important lubricant properties such as viscometric, tribological (friction and wear properties), oxidative and corrosion properties.A commercial polymethacrylate based PPD was added in different percentages and the pour points were determined in each case. Styrenated phenol(SP) was added in different concentration to coconut oil and each solution was subjected to ASTM D97 test and analysis by DSC. Refined coconut oil and other oils like castor oil, sunflower oil and keranja oil were mixed in different proportions and interesterification procedure was carried out. Interesterification of coconut oil with other vegetable oils was not found to be effective in lowering the pour point of coconut oil as the reduction attained was only to the extent of 2 to 3 °C.Chemical modification by acid catalysed condensation reaction with coconut oil castor oil mixture resulted in significant reduction of pour point (from 24 ºC to -3 ºC). Instead of using triacylglycerols, when their fatty acid derivatives (lauric acid- the major fatty acid content of coconut oil and oleic acid- the major fatty acid constituents of monoand poly- unsaturated vegetable oils like olive oil, sunflower oil etc.) were used for the synthesis , the pour point could be brought down to -42 ºC. FTIR and NMR spectroscopy confirmed the ester structure of the product which is fundamental to the biodegradability of vegetable oils. The tribological performance of the synthesised product with a suitable AW/EP additive was comparable to the commercial SAE20W30 oil. The viscometric properties (viscosity and viscosity index) were also (with out additives) comparable to commercial lubricants. The TGA experiment confirmed the better oxidative performance of the product compared to vegetable oils. The sample passed corrosion test as per ASTM D130 method.
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Eighty-eight multiparous sows were used to evaluate whether type and timing of oil supplementation during gestation influences the incidence of low birth weight (LBW). Sows were allocated (eight per treatment) commercial sow pellets (3 kg/d; control diet) or an experimental diet consisting of control diet plus 10 % extra energy in the form of excess pellets, palm oil, olive oil (OO), sunflower oil (SO) or fish oil; experimental diets were fed during either the first half (G1) or second half (G2) of gestation. Growth performance and endocrine profile of LBW ( < 1·09 kg) and normal birth weight (NBW; 1·46–1·64 kg) offspring were compared. Maternal dietary supplementation altered the distribution curve for piglet birth weight. SOG1 sows had a greater proportion of LBW piglets (P < 0·05), whilst it was reduced in the OOG1 group (P < 0·05). Growth rate of LBW piglets was lower compared with their NBW siblings (P < 0·05) when dietary supplementation was offered in G2 but were similar for G1. At birth, LBW offspring of supplemented animals possessed more fat compared with the control group (P < 0·05); LBW offspring of control animals exhibited a more rapid decline in fat free mass/kg prior to weaning. Plasma metabolites and insulin concentrations were influenced by maternal diet and birth weight. In conclusion, maternal dietary supplementation altered the distribution of piglet birth weights and improved the energy status of LBW piglets. Supplementation with MUFA during G1 reduced the incidence of LBW, whereas PUFA had the reverse effect.
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Background: The mechanisms involved in the increased mortality from coronary artery disease in British Indo-Asians are not well understood. Objectives: This study aimed to investigate whether British Indo-Asian Sikhs have higher plasma triacylglycerol concentrations, lower platelet phospholipid levels, and lower dietary intakes of long-chain n-3 polyunsaturated fatty acids (PUFAs) than do age- and weight-matched Europeans and whether moderate dietary fish-oil intake can reverse these differences. Design: A randomized, double-blind, placebo-controlled, parallel, fish-oil intervention study was performed. After a 2-wk run-in period, 44 Europeans and 40 Indo-Asian Sikhs were randomly assigned to receive either 4.0 g fish oil [1.5 g eicosapentaenoic acid (EPA) and 1.0 g docosahexaenoic acid (DHA)] or 4.0 g olive oil (control) daily for 12 wk. Results: At baseline, the Indo-Asians had significantly higher plasma triacylglycerol, small dense LDL, apolipoprotein B, and dietary and platelet phospholipid n-6 PUFA values and significantly lower long-chain n-3 PUFAs (EPA and DHA) than did the Europeans. A significant decrease in plasma triacylglycerol, plasma apolipoprotein B-48, and platelet phospholipid arachidonic acid concentrations and a significant increase in plasma HDL concentrations and platelet phospholipid EPA and DHA levels were observed after fish-oil supplementation. No significant effect of ethnicity on the responses to fish-oil supplementation was observed. Conclusions: Moderate fish-oil supplementation contributes to a reversal of lipid abnormalities and low n-3 PUFA levels in Indo-Asians and should be considered as an important, yet simple, dietary manipulation to reduce CAD risk in Indo-Asians with an atherogenic lipoprotein phenotype.
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In this study was analyzed the effect of crop year and harvesting time on the fatty acid composition of cv. Picual virgin olive oil. The study was carried out during the fruit ripening period for three crop seasons. The mean fatty acid composition of Picual oils was determined. The oils contained palmitic acid (11.9%), oleic acid (79.3%), and linoleic acid (2.95%). The content of palmitic acid and saturated fatty acids decreased during fruit ripening while oleic and linoleic acids increased. The amount of stearic and linolenic acids decreased. The amount of saturated acids, palmitic and stearic, and the polyunsaturated acids linoleic and linolenic was dependent on the time of harvest, whereas the amount of oleic acid varied with the crop year. The differences observed between crop years for both palmitic and linoleic acid may be explained by the differences in the temperature during oil biosynthesis and by the amount of summer rainfall for oleic acid content. A significant relationship was observed between the MUFA/PUFA ratio and the oxidative stability measured by the Rancimat method.
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The study assessed the efficacy of fish oil supplementation in counteracting the classic dyslipidemia of the atherogenic lipoprotein phenotype (ALP). In addition, the impact of the common apolipoprotein E (apoE) polymorphism on the fasting and postprandial lipid profile and on responsiveness to the dietary intervention was established. Fifty-five ALP males (aged 34 to 69 years, body mass index 22 to 35 kg/m2, triglyceride [TG] levels 1.5 to 4.0 mmol/L, high density lipoprotein cholesterol [HDL-C] <1.1 mmol/l, and percent low density lipoprotein [LDL]-3 >40% total LDL) completed a randomized placebo-controlled crossover trial of fish oil (3.0 g eicosapentaenoic acid/docosahexaenoic acid per day) and placebo (olive oil) capsules with the 6-week treatment arms separated by a 12-week washout period. In addition to fasting blood samples, at the end of each intervention arm, a postprandial assessment of lipid metabolism was carried out. Fish oil supplementation resulted in a reduction in fasting TG level of 35% (P<0.001), in postprandial TG response of 26% (TG area under the curve, P<0.001), and in percent LDL-3 of 26% (P<0.05). However, no change in HDL-C levels was evident (P=0.752). ANCOVA showed that baseline HDL-C levels were significantly lower in apoE4 carriers (P=0.035). The apoE genotype also had a striking impact on lipid responses to fish oil intervention. Individuals with an apoE2 allele displayed a marked reduction in postprandial incremental TG response (TG incremental area under the curve, P=0.023) and a trend toward an increase in lipoprotein lipase activity relative to non-E2 carriers. In apoE4 individuals, a significant increase in total cholesterol and a trend toward a reduction in HDL-C relative to the common homozygous E3/E3 profile was evident. Our data demonstrate the efficacy of fish oil fatty acids in counteracting the proatherogenic lipid profile of the ALP but also that the apoE genotype influences responsiveness to this dietary treatment.