959 resultados para Palm oil.


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Reducing the gap between water-limited potential yield and actual yield in oil palm production systems through intensification is seen as an important option for sustainably increasing palm oil production. Simulation models can play an important role in quantifying water-limited potential yield, and therefore the scope for intensification, but no oil palm model exists that is both simple enough and at the same time incorporates sufficient plant physiological knowledge to be generally applicable across sites with different growing conditions. The objectives of this study therefore were to develop a model (PALMSIM) that simulates, on a monthly time step, the potential growth of oil palm as determined by solar radiation and to evaluate model performance against measured oil palm yields under optimal water and nutrient management for a range of sites across Indonesia and Malaysia. The maximum observed yield in the field matches the corresponding simulated yield for dry bunch weight with a RMSE of 1.7 Mg ha?1 year?1 against an observed yield of 18.8 Mg ha?1. Sensitivity analysis showed that PALMSIM is robust: simulated changes in yield caused by modifying the parameters by 10% are comparable to other tree crop model evaluations. While we acknowledge that, depending on the soils and climatic environment, yields may be often water limited, we suggest a relatively simple physiological approach to simulate potential yield, which can be usefully applied to high rainfall environments and is considered as a first step in developing an oil palm model that also simulates water-limited potential yield. To illustrate the application possibil- ities of the model, PALMSIM was used to create a potential yield map for Indonesia and Malaysia by sim- ulating the growth and yield at a resolution of 0.1?. This map of potential yield is considered as a first step towards a decision support tool that can identify potentially productive, but at the moment degraded sites in Indonesia and Malaysia. ?

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Palm oil has been the world's main source of oil and fats since 2004, producing over 45 million tonnes in 2009. Malaysia alone has over 4·5 million hectares planted with oil palm and, based on common practice, ~300 palm fronds are pruned per hectare per year. This agricultural waste is currently either being used as roughage feed or, more frequently, being left between rows of palm trees to prevent soil erosion, or for nutrient recycling purposes. This paper proposes an alternative use for palm frond as a source of biochar. A traditional method commonly use by gardeners in Malaysia to improve soil fertility was used to produce the biochar. A shallow earth pit was dug in the ground for the carbonisation process. The process is described and the impact of carbonisation on the earth wall is analysed and presented. The process was later re-assessed by using TGA-FTIR. Most of the hemicelluloses had fully disintegrated, but the depolymerisation of the cellulose was still incomplete at the carbonisation temperature. Most of the lignin aromatic structure was still present in the biochar. The carbonisation process was repeated in the laboratory and biochar was characterised by using BET, SEM and FTIR. An adsorption isotherm study was conducted and the experimental data were fitted to the Langmuir model. The model predicted Pb2+ adsorption rates of 83·3 mg/g, Cu2+ 41·4 mg/g, Ni2+ 13·0 mg/g and Zn2+ 19·7 mg/g. Copyright © The Royal Society of Edinburgh 2012.

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European Regulation 1169/2011 requires producers of foods that contain refined vegetable oils to label the oil types. A novel rapid and staged methodology has been developed for the first time to identify common oil species in oil blends. The qualitative method consists of a combination of a Fourier Transform Infrared (FTIR) spectroscopy to profile the oils and fatty acid chromatographic analysis to confirm the composition of the oils when required. Calibration models and specific classification criteria were developed and all data were fused into a simple decision-making system. The single lab validation of the method demonstrated the very good performance (96% correct classification, 100% specificity, 4% false positive rate). Only a small fraction of the samples needed to be confirmed with the majority of oils identified rapidly using only the spectroscopic procedure. The results demonstrate the huge potential of the methodology for a wide range of oil authenticity work.

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Detection of adulteration of non-processed vegetable oil with lesser value seed oils (classic example is hazelnut in virgin olive oil) has been in the centre of scientific attention for many years and several chemical methods were proposed. The recent EC Regulation 1169/2011, however, introduces necessity for different analytical method in a more complicated matrix. From the end of 2014, food businesses required to declare the composition of the refined oil mixture in the food product label. This creates a gap since there is no analytical method currently available to perform such analysis. In the first phase the work focused on 100% oil blends of various oil species of palm oil (and derivatives), sunflower and rapeseed oil before expanding to foodstuffs. Chromatographic methods remain highly relevant although suffer from various limitations which derive from natural compositional variation. Modern multivariate techniques based on machine learning algorithms, however, when applied in FTIR, Raman spectroscopic data have a strong potential in tackling the problem.

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The design and development of a fibre optic evanescent wave refractometer for the detection of trace amounts of paraffin oil and palm oil in coconut oil is presented. This sensor is based on a side-polished plastic optical fibre. At the sensing region, the cladding and a small portion of the core are removed and the fibre nicely polished. The sensing region is fabricated in such a manner that it sits perfectly within a bent mould. This bending of the sensing region enhances its sensitivity. The oil mixture of different mix ratios is introduced into the sensing region and we observed a sharp decrease in the output intensity. The observed variation in the intensity is found to be linear and the detection limit is 2% (by volume) paraffin oil/palm oil in coconut oil. The resolution of this refractometric sensor is of the order of 10−3. Since coconut oil is consumed in large volumes as edible oil in south India, this fibre optic sensor finds great relevance for the detection of adulterants such as paraffin oil or palm oil which are readily miscible in coconut oil. The advantage of this type of sensor is that it is inexpensive and easy to set up. Another attraction of the side-polished fibre is that only a very small amount of analyte is needed and its response time is only 7 s.

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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: Compared with the postprandial events after a single meal, different events occur when a second meal is ingested 4–6 h after a first meal. There is a rapid appearance of chylomicrons in the circulation carrying fat ingested with the first meal, with a peak 1 h after the second meal. Objective: Our goal was to examine whether different dietary oils have effects on the storage of triacylglycerol as a result of differences in their digestion, absorption, and incorporation into chylomicrons. Design: A single-blind, randomized, within-subject crossover design was used to study the effects of palm oil, safflower oil, a mixture of fish and safflower oil, and olive oil on postprandial apolipoprotein (apo) B-48, retinyl ester, and triacylglycerol in the Sf > 400 fraction with the use of a sequential meal protocol. Results: For triacylglycerol, retinyl ester, and apo B-48, the time to reach peak concentration was significantly earlier after the second meal than after the first meal (P < 0.005). This was apparent with each of the dietary oils. The pattern of the apo B-48 response differed significantly among the dietary oils, with olive oil resulting in higher concentrations after both meals (P = 0.003). The ratio of triacylglycerol to apo B-48 was significantly lower after olive oil feeding than after feeding with the other oils (P = 0.02). Conclusions: The rapid entry of chylomicrons after the ingestion of a second meal 5 h after a first meal was seen with all of the oils investigated. The short-term ingestion of olive oil produced more chylomicrons than did the other dietary oils, which may have been due to differences in the metabolic handling of olive oil within the gut.

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The replacement of fish oil with vegetable based oils is a strategy which is increasingly being adopted by the aquafeed industry as an essential component to reduce the reliance on a limited supply of a natural resource, which in turn also provides cost benefits. The aim of the present investigation was to evaluate the lipid and fatty acid digestibility of a mix blend vegetable oil in juvenile Murray cod; an emerging species of increasing interest in the Australian aquaculture sector. Five semi purified experimental diets were formulated with 17% lipid originating from fish oil (FO) which was substituted in 25% increments by blended vegetable oil (VO), formulated using olive oil (12%), palm oil (43%) and linseed oil (45%) to match the major fatty acid classes of the FO.

Significant differences between the dietary treatments with regard to the lipid and individual fatty acid digestibility were recorded. This study clearly demonstrated that in Murray cod fatty acid digestibility decreases with chain length, and inversely increases relative to the degree of unsaturation. The combination of chain length, degree of unsaturation and the melting point of individual fatty acids resulted in the digestibility of PUFA > MUFA > SFA and short chain > longer chain fatty acids. Therefore, the inclusion of a mixed blend vegetable oil resulted in significantly reduced lipid digestibility in juvenile Murray cod.

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Unsustainable fishing practices have placed a heavy emphasis on aquaculture to meet the global shortfalls in the supply of fish and seafood, which are commonly accepted as the primary source of health-promoting essential omega-3 (n-3 highly unsaturated fatty acids). However, dietary fish oil is required for the production of omega-3-rich farmed fish and this commodity, in a vicious circle, is at present derived solely from wild fisheries. Decreasing global availability coupled with the highly variable price of this resource has forced the aquaculture industry to investigate the possibilities of alternative dietary lipid sources. This review attempts to compile all principal information available regarding the effects of fish oil replacement for the diets of farmed finfish, analysing the findings using a comparative approach among different cultured fish species. The review initially focuses on the present situation with regard to the production, availability and main nutritional characteristics of fish oil and the principal alternative lipid sources (such as vegetable oils and animal fats). Following this, the effects of fish oil replacement in finfish nutrition on feed quality, fish performance, feed efficiency, fish lipid metabolism, final eating quality and related economic aspects are presented and discussed.

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Four Mucor hiemalis strains (M1, M2, M3 and M4), isolated from soil at a depth of 0 - 15 cm in the Juréia-Itatins Ecology Station (JIES), in the state of São Paulo, Brazil and were evaluated for the production of γ-linolenic (GLA) and other unsaturated fatty acids. Five growth variables (temperature, pH, carbon source, nitrogen source, and vegetable oils) were studied. Liquid media containing 2% vegetable oil (palm oil, canola oil, soybean oil, sesame oil, or sunflower oil) or 2% carbohydrate (fructose, galactose, glycerol, glucose, lactose, maltose, sucrose, sorbitol or xylose) and 1% yeast extract as a nitrogen source were used. The greatest biomass production was observed with M3 and M4 strains in palm oil (91.5 g l -1) and sunflower oil (68.3 g l -1) media, respectively. Strain M4 produced greater quantities of polyunsaturated acids in medium containing glucose. The GLA production in the M4 biomass was 1,132.2 mg l -1 in glucose medium. Plant oils were inhibitors of fatty acid production by these strains. © 2007 Academic Journals.

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Research on alternative fuel for the vehemently growing number of automotivesis intensified due to environmental reasons rather than turmoil in energy price and supply. From the policy and steps to emphasis the use of biofuel by governments all around the world, this can be comprehended that biofuel have placed itself as a number one substitute for fossil fuels. These phenomena made Southeast Asia a prominent exporter of biodiesel. But thrust in biodiesel production from oilseeds of palm and Jatropha curcas in Malaysia, Indonesia and Thailand is seriously threatening environmental harmony. This paper focuses on this critical issue of biodiesels environmental impacts, policy, standardization of this region as well as on the emission of biodiesel in automotive uses. To draw a bottom line on feasibilities of different feedstock of biodiesel, a critical analysis on oilseed yield rate, land use, engine emissions and oxidation stability is reviewed. Palm oil based biodiesel is clearly ahead in all these aspects of feasibility, except in the case of NOx where it lags from conventional petro diesel.