共查询到18条相似文献,搜索用时 62 毫秒
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采用Lipozyme 435脂肪酶催化棕榈油软脂与甘油进行酯交换反应制得两种不同甘油二酯含量(62.7%与82.6%)的甘油二酯油。通过差示扫描量热仪、X射线衍射仪等表征了两种产品的熔化结晶特性和晶型等物理特性,并通过Avrami方程对其等温结晶动力学进行了研究。结果表明:脂肪酸组成相似而纯度不同的甘油二酯油,纯度高的甘油二酯油的熔点、结晶起始点均高于纯度低的甘油二酯油。非等温结晶中,两者表现出相似的热力学性质。等温结晶中,两者成核方式均为异相成核,但存在两种晶体生长机制。此外,高纯度的甘油二酯油较低纯度的甘油二酯油含有更多的β'晶型,形成的结晶网络更加细腻。 相似文献
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棕榈油和棕榈仁油的地位和现状 总被引:5,自引:0,他引:5
中国是一个油脂资源非常贫乏的国家 ,每年都要从国外进口大量的油脂以满足人民生活及工业需要。据统计 ,1997年中国进口的大豆油是 2 0 0万吨 ,棕榈油 16 2万吨 ,棕榈仁油 1 5万吨 ,其中棕榈油的消费量已位居第 4(见表 2 )。预计 ,至 2 0 0 5年 ,世界棕榈油的消费量将超过大豆油 (见表 1)。作为具有巨大市场潜力和价值的油脂资源 ,国外就棕榈油和棕榈仁油的生产、物理和化学性质及其应用等方面的研究已日趋深入[1] ,但在我国有关棕榈油和棕榈仁油的研究和介绍资料极少。为此 ,希望通过本文的介绍 ,能加深对棕榈油和棕榈仁油的了解 ,并能引起… 相似文献
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棕榈油不需要氢化——谈谈棕榈油在人造奶油、起酥油生产中的应用 总被引:1,自引:1,他引:1
在人造奶油、起酥油生产中,直接使用棕榈油、棕榈硬脂同使用氢化后的棕榈液油相比,其一可以避免氢化过程中反式酸的生成;其二可降低生产成本。 相似文献
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Nor Aini Idris Kurt G Berger Augustine S H Ong 《Journal of the science of food and agriculture》1989,46(4):481-493
Several formulations based on blends of hydrogenated palm oil (MP 41·5°C) and palm stearin (IV 44) with other liquid oils, on direct blends of palm stearin with other liquid oils, and on 100% inter-esterified palm olein, were used as feedstocks in shortening production. The shortenings were stored at 20°C over a period of one month. Physicochemical characteristics, creaming properties and baking performance of the shortenings were evaluated and compared with the best shortening on the market. Slip melting point of the shortenings ranged from 41·5 to 46·4°C. Palm-cottonseed oil shortenings had higher solid fat contents at all temperatures than palm-soya bean or palm-low erucic acid rapeseed oil shortenings. The shortenings were rich in C50, C52and C54 glycerides. Creaming power after 12 min of beating ranged from 1·55 to 1·77 cm3 g?1. Palm stearin-cottonseed (3:2) oil shortening showed the best creaming performance. The specific volume of cakes ranged, for the experimental shortening, from 90% to 101% from the control, with low erucic acid-palm blends showing the best performance. In applications for both aerated cream and cakes, inter-esterified palm olein was excellent. 相似文献
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芝麻油掺棕榈油鉴别方法的研究 总被引:2,自引:0,他引:2
以4种不同熔点棕榈油与4种芝麻油所配制的128个掺伪芝麻油样品为原料,分别采用全样脂肪酸组成分析法、Sn-2位脂肪酸组成分析法和甘三酯结构分析法对芝麻油中掺棕榈油的鉴别方法进行了研究。结果表明:在全样脂肪酸组成分析法中,当以棕榈酸为标准与芝麻油纯样和国标数据比较时,检出限分别为5%和15%。在Sn-2位脂肪酸组成分析法和甘三酯结构分析法中,当与芝麻油纯样数据比较,分别以亚油酸与棕榈酸含量比值(18:2/16:0)和β-POO(Sn-1-棕榈酸-2,3-二油酸甘油酯)含量为判断标准时,检出限分别为20%和12%。综合这3种方法的检出限高低及分析操作难易程度,初步得出结论:在芝麻油掺棕榈油的鉴别方法中,全样脂肪酸组成分析法是最好的鉴别方法,其余2种方法一般不优先采用,但可作为对上述方法的验证与补充。 相似文献
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Dere A. Okiy Winifred B. Wright Kurt G. Berger Ian D. Morton 《Journal of the science of food and agriculture》1978,29(12):1061-1068
Palm oil has been treated by partial lipase hydrolysis and by interesterification with excess glycerol and the effects on the chemical and physical properties have been investigated. Lipase hydrolysis preferentially removes unsaturated acids and the neutral glycerides remaining after removal of the free fatty acids therefore have an increased solids content at 20°C. Both differential scanning calorimetry (d.s.c.) and X-ray examination show that the crystalline phases present above 20°C are more heterogeneous after lipase treatment. Interesterification results in a mixture of tri- and diglycerides with an increased solids content at 20°C and a marked tendency to form β phase crystals. Some potential practical applications are discussed. 相似文献
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旨在为植物油复杂反应体系的动力学研究提供新的思路,以棕榈油为研究对象,以面制品为煎炸物,在140、150、160、180℃下进行连续煎炸模拟试验,测定不同煎炸温度下不同煎炸时间煎炸油中极性组分含量,并通过集总的方法建立极性组分含量与煎炸温度和煎炸时间的动力学模型。结果表明:在140、150、160℃下煎炸36 h均没有达到煎炸油废弃点,而180℃下煎炸24 h即到达废弃点;棕榈油煎炸生成极性组分的过程为零级反应,反应活化能为35.98 kJ/mol,极性组分含量随煎炸时间延长线性增长;通过建立的模型预测不同温度下棕榈油煎炸的极限煎炸时间,预测结果与模拟试验结果相符。综上,通过集总的方法所建立的棕榈油煎炸生成极性组分的动力学模型可靠,所使用的集总动力学的研究方法可以引用至其他植物油的煎炸反应体系中。 相似文献
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Etor E. K. Takyi 《Journal of the science of food and agriculture》1981,32(9):941-947
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. 相似文献