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以candida rugosa脂肪酶为催化剂,采用微波辅助酶法合成植物甾醇油酸酯的研究。通过单因素和正交试验考察反应时间、微波功率、催化剂用量、料液摩尔比4个因素对植物甾醇油酸酯酯化率的影响,优化得出植物甾醇油酸酯的最佳合成工艺条件:反应时间36 min,微波功率550 W,催化剂用量9%,料液摩尔比4∶1。在此工艺条件下合成产物的酯化率为75.26%,经分离纯化后的产物纯度可达到91.19%。气相色谱-质谱及红外光谱检测分析结果表明微波辅助酶法合成产物为甾醇油酸酯。 相似文献
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脂肪酶催化合成α-亚麻酸植物甾醇酯的工艺研究 总被引:1,自引:0,他引:1
酶法催化合成甾醇酯工艺是当前的研究重点之一.本文首次研究了脂肪酶催化合成α-亚麻酸植物甾醇酯,重点通过单因素和正交实验考察了多种脂肪酶、有机溶剂及其添加量、物料比、反应温度、反应时间等多种因素对酯化率的影响,并采用薄层色谱法和红外光谱法对产品进行了分析鉴定.研究结果表明,选取Novozyme435和异辛烷作为合成反应的催化剂和溶剂,添加量分别为5%和1:1.6(溶剂体积:底物质量),在α-亚麻酸和甾醇摩尔比为3:1、反应温度为55℃条件下反应24h时,酯化率达到40.65%,产品经精制后α-亚麻酸植物甾醇酯纯度能达到85%以上.通过本文的研究,成功得到了一种酶法催化合成α-亚麻酸植物甾醇酯的工艺. 相似文献
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无溶剂直接酯化法合成α-亚麻酸植物甾醇酯工艺研究 总被引:1,自引:1,他引:0
研究了植物甾醇与α-亚麻酸无溶剂直接酯化法合成α-亚麻酸植物甾醇酯的最佳工艺条件.通过单因素试验研究了α-亚麻酸和植物甾醇不同质量比、催化剂添加量、反应时间及反应温度对α-亚麻酸植物甾醇酯酯化率的影响.通过正交试验对α-亚麻酸植物甾醇酯合成工艺进行优化,最终得到优化工艺条件为:即真空度为0.03~0.04 MPa,α-亚麻酸与植物甾醇的质量比4:1,催化剂量为2.5%,反应时间为8 h,反应温度140℃,在此条件下,α-亚麻酸植物甾醇酯的酯化率为(98.88±0.984)%.因此,通过本论文的研究得到了一种绿色、安全、高效的α-亚麻酸植物甾醇酯合成工艺. 相似文献
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有机相脂肪酶催化合成共轭亚油酸β-谷甾醇酯的研究 总被引:5,自引:2,他引:5
研究了有机相脂肪酶催化合成共轭亚油酸β-谷甾醇酯的工艺条件,同时研究了甾醇酯的分离纯化方法。优化后的共轭亚油酸β-谷甾醇酯合成奈件为:在正已烷介质中,β-谷甾醇浓度为0.05mmol/mL,酸醇摩尔比为1:1,4A分子筛用量为60mg/mL,酶用量为20mg/mL,在50℃水浴恒温振荡器中连续反应72h,反应酯化率可达72.63%。用硅胶柱层析分离方法,以环已烷/元水乙醚(19:1,V/V)溶剂体系做流动相可以达到较好的分离效果。 相似文献
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以脂肪酶Novozym435为催化剂,在有机溶剂中催化合成共轭亚油酸植物甾醇酯.筛选出的最佳溶剂为正丁醇.采用单因素结合正交试验的方法,以甾醇酯化率为考察指标,对反应温度、反应时间、醇油摩尔比以及酶添加量进行了参数优选.结果显示,醇油摩尔比及酶添加量对酯化率影响不显著,反应时间对酯化率有一定影响,反应温度对酯化率的影响极显著.最优条件为:反应温度55℃,醇油摩尔比1:1,酶添加量8%,反应时间48 h.在此条件下,进行了共轭亚油酸植物甾醇酯酶促催化制备,并以气相色谱及红外光谱法对纯化后产物进行了分析确证. 相似文献
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酶法水解麦胚制取持水剂的研究 总被引:1,自引:0,他引:1
采用响应面分析方法研究了酶法水解麦胚制取持水剂的生产工艺,并对产品应用于香肠中的抗氧化效果进行了试验。试验结果表明:酶法水解麦胚制取持水剂的优化工艺参数为:对10%的麦胚乳400ml,反应温度为44.4℃,反应时间为4h,酶与底物浓度比为860μ/g。经优化工艺生产的持水剂的水分活度为0.896,所对应的水解度为26.5%。应用于香肠可显著提高其货架寿命。 相似文献
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廊坊百冠包装机械有限公司(原廊坊包装设备制造总公司)作为专业的饮料机械制造企业,拥有近30年的设计经验,掌握了液体灌装等多项核心专利技术,成功开发了一系列中、大型灌装机组,并已经具备了产业化条件,在行业中处于领先地位。 相似文献
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网印折光装饰技术的出现,给我国网印包装行业带来了机会,论述了生产高质量网印折光包装品必须具备的三个条件;制作高质量的网印版;创造2高洁净的印刷环境;培养高素质的操作人员和添加高精度的印刷设备,着重介绍了制作高质量网印版的各工序。 相似文献
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This study compared genetic evaluations from 3 test-day (TD) models with different assumptions about the environmental covariance structure for TD records and genetic evaluations from 305-d lactation records for dairy cows. Estimates of genetic values of 12,071 first-lactation Holstein cows were obtained with the 3 TD models using 106,472 TD records. The compound symmetry (CS) model was a simple test-day repeatability animal model with compound symmetry covariance structure for TD environmental effects. The ARs and ARe models also used TD records but with a first-order autoregressive covariance structure among short-term environmental effects or residuals, respectively. Estimates of genetic values with the TD models were also compared with those from a model using 305-d lactation records. Animals were genetically evaluated for milk, fat, and protein yields, and somatic cell score (SCS). The largest average estimates of accuracy of predicted breeding values were obtained with the ARs model and the smallest were with the 305-d model. The 305-d model resulted in smaller estimates of correlations between average predicted breeding values of the parents and lactation records of their daughters for milk and protein yields and SCS than did the CS and ARe models. Predicted breeding values with the 3 TD models were highly correlated (0.98 to 1.00). Predicted breeding values with 305-d lactation records were moderately correlated with those with TD models (0.71 to 0.87 for sires and 0.80 to 0.87 for cows). More genetic improvement can be achieved by using TD models to select for animals for higher milk, fat, and protein yields, and lower SCS than by using models with 305-d lactation records. 相似文献
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Pork treatments were restructured with: (1) 1.15 g/100 g Activa™ TG-RM (TG); (2) 10 g/100 g Fibrimex™ (control-10); (3) 5 g/100 g Fibrimex™(control-5); (4) 5 g/100 g Fibrimex™ plus 0.3 g/100 g sodium tripolyphosphate (STP). Color, proximate analysis, texture profile analysis, cook yield, dimensional change, and bind strength of raw and cooked treatments were evaluated. TG had the strongest raw and cooked bind (P?0.05). Hardness and gumminess were similar for all treatments (P>0.05); however, TG resulted in the most cohesiveness (P?0.05). Consumer analysis was performed on treatments 1, 2 and 4. Consumers rated TG higher for flavor and overall acceptability (P?0.05) with no differences among treatments for texture (P>0.05). Restructured pork steaks formulated with the combination of STP and 5 g/100 g Fibrimex™ were rated similar to 10 g/100 g Fibrimex™ in texture and flavor indicating that steaks formulated with the STP treatment are acceptable to consumers as well as being economically viable. 相似文献
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本文讨论了猪皮制革的现状,分析其成因,在此基础上阐明了猪皮制革必须适应市场经济的观点,并提出了猪皮制革走出低谷的若干具体对策。 相似文献