Effect of γ-irradiation on enzymatic digestion of oil palm empty fruit bunch

Effect of γ-irradiation and combination treatment with alkali on oil palm empty fruit bunch (EFB) was studied to enhance the efficiency of enzymatic digestibility. γ-Irradiation enhanced the enzymatic digestibility, and the amounts of released galacturonic acid and neutral sugars from EFB by Driselase were increased with an increase in irradiation dose. The main components of neutral sugars released from EFB were glucose and xylose. EFB treated with alkali and 50 kGy irradiation released 1200 μg g^?1 of xylose that was twice amount of glucose showing that the combination treatment was effective especially to increase the digestibility of xylan.     

Effect of gamma irradiation on microorganisms and components in empty fruit bunch and palm press fibre of oil palm wastes

The effects of irradiation on microbiological load and chemical components of empty fruit bunch (EFB) and palm press fibre (PPF) were investigated as the preliminary study for upgrading of oil palm wastes to animal feeds by fermentation. The initial contamination of microorganisms in both EFB and PPF was very high and there is no significant difference between the samples collected from various palm oil mills. The dose required to eliminate below the detectable level was more than 15 kGy for total aerobic bacteria, but 5–6 kGy is enough for fungi. The contents of holocellulose and lignin were c 60% and 25%, respectively, in both EFB and PPF, and the change in components by irradiation was small. EFB and PPF have a high water holding capacity suggesting that they are suitable substrates for fermentation. These results show that the irradiation by 5–10 kGy on EFB and PPF is applicable for the pasteurisation of fermentation media without any significant change in components.     

Preservation of oil palm fruit and oil palm fruit mesocarp by gamma irradiation

Experiments were conducted to determine the potential of gamma radiations in the extension of the shelf-life of oil palm fruit and oil palm fruit mesocarp. In the course of the experiment, it was observed that even though palm fruits in their harvested form, went bad within 3 days post-harvest, their shelf-life can be extended to at least 2 months through preparation of dry oil palm fruit mesocarp. Furthermore, despite the fact that gamma radiation cannot be used to prolong the shelf-life of oil palm fruit proper, it can be used to drastically reduce the mould load in the dry palm fruit mesocarps, thereby further enhancing their keeping quality and consumer acceptance. Chemical and organoleptic analyses of fat extracted from irradiated, dry oil palm fruit mesocarp show that there is practically no radiation effect. The significance of these observations is discussed in relation to the possible acceptance of radiation-preservation of oil palm fruit mesocarp commercially.     

微波辅助棕榈油制备生物柴油的研究

用棕桐油和甲醇为原料,KOH为催化剂,利用微波辅助酯交换反应制备生物柴油。考察醇油摩尔比、催化剂用量、反应时间和反应温度对酯交换反应的影响。结果表明,制备生物柴油的最适条件为醇油摩尔比7：1,反应温度50℃,反应时间3min,催化剂用量1．2％。在此反应条件下生物柴油转化率可达93％。经性能比较所得生物柴油主要质量指标达到我国和美国生物柴油质量标准。     

Analysis of a complex mixture of carotenes from oil palm (Elaeis guineensis) fruit extract

A carotene extract from the fruits of the oil palm (Elaeis guineensis) was analysed by HPLC employing a C₃₀ column for better separation efficiency. A multitude of cis-isomers of α-, β- and γ-carotene were separated. Detailed assignment was possible by subjecting pure standards of α-, β- and γ-carotene to isomerisation and comparing spectral data and order of elution to literature data. α- and β-carotene were found to be the most abundant carotenoids comprising 12.3% and 17.9%, respectively, of a (roughly) 30% oil suspension of oil palm carotenes in vegetable oil. A large proportion (about 40%) of α- and β-carotene was in the form of cis-isomers. The γ-carotene content was found to be 0.38% and other carotenes like phytoene, phytofluene, ζ-carotene, lycopene and possibly β-zeacarotene were found as well but were not quantified.     

基于微波预处理油菜籽的压榨油和浸出油理化品质比较

微波预处理油菜籽可显著提高压榨出油率,但压榨后的饼粕中仍残留油脂,可采用浸出法提取饼中残油。为比较压榨油和浸出油的主要理化品质,在2450MHz、800W的微波条件下,分别对油菜籽预处理0～7min,冷却至室温后压榨制油,继而对饼粕中残油用正己烷萃取。结果表明,微波处理时间、压榨和浸出的制油方式对菜籽油酸价、过氧化值、p-茴香胺值、水分含量均有显著影响（P〈0.05）。压榨油和浸出油的酸价、p-茴香胺值随微波时间的延长而增加,过氧化值呈先增加后减少的趋势,浸出油酸价、过氧化值和p-茴香胺值高于压榨油。压榨油水分含量随微波时间的延长而增加,而浸出油的则减少,压榨油水分含量高于浸出油。压榨油和浸出油的色泽（罗维朋比色）随微波时间的延长逐渐变深,浸出油色泽更深;加热试验（至280℃）中压榨油无析出物,而浸出油产生絮状析出物。由此可见基于微波预处理油菜籽的压榨油仅需水洗、过滤或离心分离即可满足国家标准,浸出油则需要进行脱胶、脱酸、脱色等精炼处理。     

Determination of oil palm fruit phenolic compounds and their antioxidant activities using spectrophotometric methods

There is scarce information on the phenolics of oil palm fruits (Elaeis guineensis). In this study, phenolics were extracted from oil palm fruits and analysed using spectrophotometry for information on the different types of palm phenolics and their antioxidative activities. Analyses of the total phenolic content (TPC), total flavonoid content (TFC), o‐diphenols index, hydroxycinnamic acid index, flavonols index and phenol index showed ranges between 5.64 and 83.97 g L^?1 gallic acid equivalent (GAE), 0.31–7.53 g L^?1 catechin equivalent, 4.90–93.20 g L^?1 GAE, 23.74–77.46 g L^?1 ferulic acid equivalent, 3.62–95.33 g L^?1 rutin equivalent and 15.90–247.22 g L^?1 GAE, respectively. The antioxidant assay, 2,2‐diphenyl‐2‐picrylhydrazyl radical scavenging assay, showed antioxidative activities in all the extracts with results ranging from 4.41 to 61.98 g L^?1 trolox equivalent. The high antioxidant activities of the oil palm fruit phenolics were also found to increase with increasing TPC and TFC.     

Improvement of palm oil and sunflower oil blends by enzymatic interestrification

Palm oil (PO) and sunflower oil (SFO) blends with varying proportions were subjected to enzymatic interesterification (EIE) using a 1,3‐specific immobilised lipase. The interesterified blends were evaluated for their slip melting point (SMP), solid fat content (SFC) at 10–40 °C, p‐anisidine value, peroxide value, free fatty acids (FFA), induction period of oxidation at 110 °C (IP110) and composition of fatty acids by gas chromatography. Under EIE treatment, the blends of PO and SFO in different proportions (20:80, 40:60, 50:50, 60:40 and 80:20) had saturated and unsaturated fatty acid content in the range of 37.6–52.0% and 48.0–62.4%, respectively. The blends showed a considerable reduction in their SFC, SMP, peroxide value and oxidative stability at 110 °C, but presented increase in FFA and p‐anisidine value. The optimum condition for minimising the fatty acid in oil was obtained, at 64 °C, using 8.9% enzyme and 3 h reaction time.     

The absence of endogenous lipase from oil palm mesocarp

Oil palm (Elaeis guineensis Jacq.) fruit mesocarp had higher levels of free fatty acids at the ends of the fruits than in the middle, and microscopy showed that yeasts penetrate the mesocarp via the scars at each end. Very low levels of esterase activity, probably not due to a lipase, were detected in mesocarp extracts by using 4-methyl umbelliferone esters as substrates, but no activity against triacylglycerols could be found. In bruising and storage trials, the only variable that correlated (P<0.01) with free fatty acid level was yeast and mould count. It is concluded that yeasts and moulds are the source of lipolytic activity in oil palm mesocarp, and there is no evidence for an endogenous lipase.     

The isolation of volatile oil from coriander fruit by steam distillation

The isolation of the essential oil of coriander fruit by steam distillation is described. The chemical composition of the oil was investigated by means of gas-liquid chromatography, column chromatography and coupled gas chromatography-mass spectrometry. The 18 most important components were identified and quantified.     

拉曼光谱快速鉴别花生油掺棕榈油的研究

本文利用激光拉曼光谱实现了纯花生油中掺棕榈油的快速定性鉴别和定量分析.通过因子分析法的二维因子图,能够定性鉴别纯花生油和掺棕榈油的花生油;通过最小二乘法建立的拉曼光谱相对峰强度（Y）与掺入棕榈油的质量百分数（X）之间的线性方程（Y=-0.233 7X ＋0.506 8,R2=0.995 9）能够实现纯花生油掺棕榈油的定量分析.     

Analysis of mesocarp and kernel oils from the American oil palm and F1 hybrids with the West African oil palm

The mesocarp oil of the American oil palm is more unsaturated than that of the West African oil palm. Mesocarp oils obtained from F₁ hybrids of these two oil palms exhibit an intermediate degree of unsaturation. Hybrid kernel oils are similar in composition to that of their West African oil palm parent, whereas kernel oils from the American oil palm are considerably more unsaturated and exhibit a unique fatty acid composition among seed fats of the Palmae family.     

碳同位素比值法检测棕榈油掺入玉米油的研究

用碳同位素比值法对玉米油的掺伪进行研究.利用气相色谱-燃烧-同位素比值质谱仪获得玉米油与棕榈油主要脂肪酸的δ13C值,构建其混合油中3种主要脂肪酸的δ13C值－混合比例的标准曲线.结果表明,玉米油与棕榈油的δ13C值差异很大,把棕榈油和玉米油进行掺和,可以检出15%以上的掺伪水平.     

世界棕榈油的生产贸易及我国消费现状分析

棕榈油作为世界主要油脂品种之一,其生产量和贸易量均位居世界第一,在植物油生产和消费市场中占有极其重要的地位。详细论述了近年世界棕榈油的生产及进出口贸易情况;并对近年我国棕榈油的进口数量、品种、消费以及分提加工现状进行了分析。     

棕榈油中生育酚和生育三烯酚的HPLC测定

建立了棕榈油中生育酚和生育三烯酚的准确、快速的HPLC分析方法。选用Nucleosil硅胶柱正相分离,以正己烷-异丙醇为流动相,梯度洗脱,在紫外波长292nm下进行检测,获得较理想的分离效果。该方法线性范围为0.2275～1.3031mg/mL,平均加样回收率为100.17%,RSD=0.5905%。     

Lipid production by Lipomyces starkeyi using sap squeezed from felled old oil palm trunks

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Deterioration of shelled oil palm kernels caused by seedborne fungi

Autoclaved oil palm kernels were inoculated with spores of seedborne isolates of either Aspergillus flavus, A. niger, Penicillium chrysogenum, P. janthinellum, Paecilomyces varioti, Syncephalastrum racemosum or Fusarium oxysporum. At 0, 2, 4 and 8 weeks after inoculation, determinations were made of the moisture content, oil, free fatty acids (FFA), sugars and protein nitrogen. The principal biochemical changes induced by these fungi were increases in moisture content and FFA, decreases in total oil and total sugars and a degradation of protein nitrogen. Aspergillus flavus caused the greatest changes, and P. varioti caused the least changes under the moisture conditions of this experiment. The main type of deterioration was hydrolytic rancidity of the oil, resulting in a dark reddish-orange-coloured oil and a discoloration of the kernel meal.     

K2CO3/Al2O3催化大豆油甘油解制备单甘酯的研究

利用K2CO3/Al2O3固体碱催化大豆油甘油解制备单甘酯.在单因素试验的基础上,利用正交试验对单甘酯制备条件进行优化,得到最优条件为:反应温度210℃,反应时间1.5h,催化剂添加量0.8％(占大豆油质量),大豆油与甘油物质的量比1∶3.在最优条件下,单甘酯含量达到58.26％.经过两级分子蒸馏,单甘酯含量高达95.69％,回收率为90.8％.