麦胚中天然维生素E的SFE-CO_2最佳提取工艺的研究

本研究以小麦胚芽为原料 ,利用超临界流体萃取技术从麦胚中提取天然维生素E。将萃取压力、萃取温度和CO2 流量作为中心组合旋转设计的变量 ,进行响应曲面分析 ,确定了其最佳工艺参数和条件。结果表明 :麦胚中天然维生素E的超临界CO2 提取的最佳工艺参数为萃取压力为2 9 1MPa ,萃取温度为 316K ,CO2 流量为 2ml/min。     

超临界CO2提取五味子木脂素的工艺研究

目的 研究超临界CO2流体提取(SFE-CO2)北、南五味子木脂素的工艺.方法 以五味子总木脂素提取率为考察指标,以提取压力、提取温度、CO2流量等3项因素设计3个水平进行正交试验设计,确定最佳工艺.用薄层扫描色谱法测定提取物中4种主要木脂素(五味子甲素、五味子乙素、五味子酯甲和五味子醇甲)的含量,并与传统的乙醇提取法比较.结果 超临界CO2流体提取五味子木脂素的优选工艺为:提取压力25 MPa,提取温度35℃,CO2流量2 L/min.北、南五味子总木脂素的平均提取率分别为93.2%、95.5%,提取物纯度分别为13.0%、9.2%,北五味子提取物中五味子乙素含量2.89%.结论 SFE-CO2法提取效率高、选择性好、操作简便,明显优于传统的乙醇提取法,可用于提取五味子木脂素.     

超临界CO_2萃取与浸渍法制备白刺果油及其化学成分的分析与比较

为了促进白刺属植物在医药、食品、化工等领域中的应用,文中采用超临界CO2流体萃取法和溶剂浸渍法提取西伯利亚白刺果油,并用气相色谱-质谱联用技术(GC-MS)对其化学成分进行了分析,从超临界CO2萃取、浸渍法提取出的白刺果油中分别鉴定出26种成分。主要化学成分是亚油酸、油酸、γ-生育酚、VE(α-生育酚)、菜油甾醇、γ-谷甾醇、二十八碳烷、二十七碳烷等。     

超临界流体萃取芦荟苷的研究

研究了带夹带剂的超临界流体萃取芦荟中芦荟苷的工艺,讨论了萃取条件(温度和压力)、萃取时间等对芦荟苷萃取率的影响。通过正交试验对萃取釜条件(夹带剂用量、萃取温度和压力)进行了优化。结果表明,分离釜的温度和压力、CO2流量等对萃取效率影响较小;最佳工艺条件为:静萃取时间为40 min,动萃取时间为30 min,以乙醇作夹带剂、乙醇用量250 mL/100g芦荟、萃取温度30℃、萃取压力25 MPa。在此条件下萃取量达1.78%。     

超临界CO2萃取核桃油的研究

研究了影响核桃油超临界CO2流体萃取的因素,在试验条件下,其影响因素次序为:夹带剂、萃取压力、CO2体积,萃取温度影响不大.优化了超临界CO2流体萃取核桃油的工艺条件:夹带剂无水乙醇,用量为投料量的质量分数的10%;萃取压力30 MPa,萃取温度35℃,萃取时间3.5 h,CO2流量15～20kg/h.用气相色谱法分析了超临界CO2流体萃取核桃油的脂肪酸酸组成和含量,其不饱和脂肪酸含量较高.     

主流烟气中烟草特有亚硝胺超临界流体萃取与分析

运用超临界CO2流体萃取与液相色谱串联质谱相结合的方法对主流烟气的四种烟草特有亚硝胺进行了萃取与分析,结果表明:在夹带剂-甲醇流量为0.2mL/min、压力为350bar、萃取温度为70℃、CO2的流量为2L/min的条件下,静态萃取20min、动态萃取30min,烟草特有亚硝胺的萃取率达95%以上。本方法实现了\     

超临界CO2在填料塔中连续浓缩鱼油DHA工艺研究

突破鱼油DHA间歇萃取浓缩的方法 ,设计建造了超临界CO2 在内径 14mm高 1.8m的填料塔中连续萃取浓缩鱼油DHA的流程。以塔底DHA的回收率和纯度为考察指标 ,初步得到了工艺参数的范围 :分离柱压为 8MPa - 17MPa ,以 10MPa - 13MPa为宜 ;CO2 流量为 2L/min -15L/min ;鱼油进料流量以 0 .5ml/min - 2ml/min为宜 ;柱的适宜的温度分布是 36℃ - 85℃。     

超临界CO2流体萃取苦瓜叶中黄酮的研究

研究超临界流体萃取苦瓜叶黄酮的影响因素,并对提取工艺进行优化设计.在单因素试验和正交试验的基础上,得到超临界萃取工艺的最优化条件:以用量为1∶1(V∶m)的95％乙醇浸润1h,夹带剂体积与原料质量比2∶1,CO2流量22L/h、萃取压力28MPa、萃取温度44℃,萃取时间150min.该工艺条件下,黄酮的提取率可达到3.69％.     

超临界CO2流体技术萃取花生油的工艺优化

采用超临界CO2流体萃取技术提取花生油.通过单因素实验及正交实验研究了萃取压力、萃取温度、CO2流量和萃取时间等因素对油脂萃取率的影响,确定了超临界CO2流体萃取技术提取花生油的最佳工艺条件.结果表明,在实验范围内各影响因素对花生油萃取率作用的大小顺序依次为:萃取压力>萃取温度>CO2流量>萃取时间.超临界CO2流体萃取技术提取花生油的最佳工艺参数为:萃取压力25MPa,萃取温度45℃,CO2流量18kg/h,萃取时间150min,在该工艺条件下花生油萃取率达到49.87%.     

麦胚中天然维生素E的SFE—CO2最佳提取工艺的研究

本研究以小麦胚芽为原料,利用超临界流体萃取技术从麦胚中提取天然维生素E。将萃取压力、萃取温度和CO2流量作为中心组合旋转设计的变量,进行响应曲面分析,确定了其最佳工艺参数和条件。结果表明：麦胚中天然维生素E的超临界CO2的取的最佳工艺参数为萃取压力为29.1MPa,萃取温度为316K,CO2流量为2ml/min。     

Lipase-catalyzed interesterification of high oleic sunflower oil and fully hydrogenated soybean oil comparison of batch and continuous reactor for production of zero trans shortening fats

Lipase-catalyzed interesterification of high oleic sunflower oil (HO) and fully hydrogenated soybean oil (FHSBO) at different weight ratios (55:45, 60:40, 65:35 and 70:30, HO:FHSBO) was carried out in both a batch-type reactor (BA) and a packed-bed reactor (PBR) to produce zero trans shortening. Interesterified products in both PBR and BA consisted of 34-46 g/100 g saturated fatty acids (SFA) (mainly stearic acid) and 54-66 g/100 g unsaturated fatty acid (USFA) (mainly oleic acid). After interesterification the physical characteristics such as melting point and solid fat content (SFC) were changed in each product. The differential scanning calorimetry (DSC) result showed that SFC content in PBR was higher than that in BA at each measured temperature. Decrease in tocopherols was also observed, however, the PBR product contained much higher amounts of tocopherols than BA product.     

从脱臭馏出物提取天然生育酚研究进展

天然维生素E(生育酚)是一种优良生理活性物质和良好抗氧化剂,具有广阔开发前景和市场需求。该文介绍植物油精炼加工副产物脱臭馏出物主要成分及天然维生素E生物活性,重点综述从不同植物油脱臭馏出物中提取生育酚方法,为扩大天然生育酚制备途径和提高油脂加工业经济效益提供参考。     

Effect of menadione (vitamin K3) addition on lipid oxidation and tocopherols content in plant oils

The effect of added menadione (vitamin K3) on stored corn and wheat germ oil on the dissolution and dimerization of natural tocopherols and autoxidation of triacylglycerols was investigated. Samples of corn and wheat germ oils pure and with added menadione were stored at +20 degrees C in brown and transparent glass bottles. During storage their peroxide value, changes of the content of fatty acids and dissolution of tocopherols were measured. Destruction of individual tocopherols in tested oils with menadione stored in both dark and transparent glass bottles was greater than in the oil samples without menadione. However, the degradation of individual tocopherols was different in each oil. Addition of menadione to the both oils resulted in accelerated the process of autoxidation of these oils. The corn oil stored in transparent bottles was oxidized faster than the one stored in brown bottles. The pro-oxidant activity of menadione was additionally activated by light. In contrast, in the case of germ oil, the process of autoxidation was very fast regardless of sort of container. Addition of menadione to the plant oils influenced the dissolution of natural tocopherols but did not influence the dimerization of tocopherols. As from the experiment, the addition of menadione to the oils decreased their nutritive value.     

Vitamin E and Oxidative Stability of Soya Bean Oil Prepared with Beans at Various Moisture Contents Roasted in a Microwave Oven

Whole soya beans ( Glycine max ) at various moistures (96, 382 and 519 g kg⁻¹) were roasted by exposure to microwaves at a frequency of 2450 MHz and the effects on the tocopherols of soya beans were studied in rela-tion to chemical changes in the oils. The amounts of α-, β-, γ- and δ-tocopherols in the soya beans before microwave treatments ranged from 62 to 187, 43 to 89, 673 to 757 and 542 to 593 mg kg⁻¹ oil, respectively. Increasing moisture contents by soaking prevented, not only the reduction of tocopherols but also, the oxidative deterioration of soya bean oils during microwave roasting. The amounts of tocopherols still remained >80% of the original level in soaked soya bean oils after 20 min of roasting, and microwave roasting after soaking caused no significant differences ( P> 0·05, with few exceptions) in the chemical changes of the oils in comparison with those before soaking. These results implied that microwave roasting after soaking would be effective in making full-fat soya flour with high vitamin E without a burnt odour and browning from raw beans.     

Production of trans‐Free Margarine with Stearidonic Acid Soybean and High‐Stearate Soybean Oils‐Based Structured Lipid

Abstract: Omega‐3 fatty acids (n‐3 FAs) have been positively associated with prevention and treatment of chronic diseases. Intake of high amounts of trans fatty acids (TFAs) is correlated with increased risk of coronary heart disease, inflammation, and cancer. Structured lipid (SL) was synthesized using stearidonic acid (SDA) soybean oil and high‐stearate soybean oil catalyzed by Lipozyme^® TLIM lipase. The SL was compared to extracted fat (EF) from a commercial brand for FA profile, sn‐2 positional FAs, triacylglycerol (TAG) profile, polymorphism, thermal behavior, oxidative stability, and solid fat content (SFC). Both SL and EF had similar saturated FA (about 31 mol%) and unsaturated FA (about 68 mol%), but SL had a much lower n‐6/n‐3 ratio (1.1) than EF (5.8). SL had 10.5 mol% SDA. After short‐path distillation, a loss of 53.9% was observed in the total tocopherol content of SL. The tocopherols were lost as free tocopherols. SL and EF had similar melting profile, β’ polymorph, and oxidative stability. Margarine was formulated using SL (SLM) and EF (RCM, reformulated commercial margarine). No sensory difference was observed between the 2 margarines. The SL synthesized in this study contained no TFA and possessed desirable polymorphism, thermal properties, and SFC for formulation of soft margarine. The margarine produced with this SL was trans‐free and SDA‐enriched. Practical Application: The current research increases the food applications of stearidonic acid (SDA) soybean oil. trans‐Free SDA containing SL was synthesized with desirable polymorph, thermal properties, and SFC for formulation of soft margarine. The margarine produced with this SL had no trans fat and had a low n‐6/n‐3 ratio. This may help in reducing trans fat intake in our diet while increasing n‐3 FA intake.     

Influence of added menadione (vitamin K3) on dissolution and dimerization of tocopherols and autoxidation of triacylglycerols during storage of plant oils

The effect of added menadione (vit. K3) to stored rapeseed and soybean oil on the dissolution and dimerization of natural tocopherols and autoxidation of triacylglycerols was studied. Commercial rapeseed and soybean oils with added menadione and pure oil were stored at +20 degrees C in brown and transparent glass bottles. During storage their peroxide value, changes of the content of fatty acids and dissolution of tocopherols were measured. Destruction of individual tocopherols in tested oils with added menadione stored in both dark and transparent glass bottles were greater than in the oil samples without menadione. However, the degradation of individual tocopherols was different in each oil. Addition of menadione to the rapeseed and soybean oils resulted in the accelerated process of autoxidation of these oils. The oxidative state of the oils was lower in the oils stored in transparent bottles than in the oils stored in brown bottles. The prooxidant activity of menadione was additionally activated by light. Menadione added to the vegetable oils influenced the dissolution of natural tocopherols as well as their dimerization. It is conduced that addition of menadione to vegetable oils decreases their nutritive value.     

Effect of menadione (vitamin K3) addition on lipid oxidation and tocopherol content in plant oils

The effect of added menadione (vitamin K₃) to stored corn and wheat germ oil on the dissolution and dimerization of natural tocopherols and auto‐oxidation of triacylglycerols were investigated. Samples of corn and wheat germ oils pure and with added menadione were stored at +20°C in brown and transparent glass bottles. During storage their peroxide value, changes of the content of fatty acids and dissolution of tocopherols were measured. Destruction of individual tocopherols in tested oils with added menadione stored in both dark and transparent glass bottles was greater than in these oil samples without menadione. However, the degradation of individual tocopherols was different in each oil. Addition of menadione to the both oils resulted in accelerated the process of auto‐oxidation of these oils. The corn oil stored in transparent bottles was oxidized faster than the one stored in brown bottles. The pro‐oxidant activity of menadione was additionally activated by light. In contrast, in the cause of germ oil, the process of auto‐oxidation was very fast regardless of sort of container. Addition of menadione to the plant oils influenced the dissolution of natural tocopherols but did not influence the dimerization of tocopherols. As from the experiment, the addition of menadione to the oils decreased their nutritive value.     

Tocopherol Deposition in the Muscle of Atlantic Salmon (Salmo salar)

The deposition of four tocopherols (α, β, γ and δ) was studied in the muscle of Atlantic salmon (Salmo salar) smolts reared in seawater. γ-Tocopherol was deposited in proportion to the a-tocopherol content of the diet when both were added to the diet in a natural mixture. Both δ- and β-tocopherols were deposited in the muscle to a lesser extent than the a and γ forms. An equilibrium among tocopherols in muscle was reached in 15 wk.     

γ-生育三烯酚的生物活性及其作用机理研究进展

维生素E包括生育酚和生育三烯酚两个亚族,每个亚族有四种单体（α,β,γ和δ）。相较于其他维生素E单体,γ-生育三烯酚（γ-T3）具有更好的抗肿瘤、神经保护、降低胆固醇、抗炎以及抑制脂肪产生的作用。本文旨在综述γ-T3的生物活性及其作用机理,提出目前γ-T3生物活性研究中存在的问题,并对其研究方向进行展望。      

Loss of tocopherols and formation of degradation compounds at frying temperatures in oils differing in degree of unsaturation and natural antioxidant content

Samples of oils of different degrees of unsaturation, namely palm olein, olive oil, high‐linoleic sunflower oil, high‐oleic sunflower oil, rapeseed oil and soybean oil, were heated at 180 °C for 2, 4, 6, 8 and 10 h in the presence or absence of their natural antioxidants. Also, tocopherol‐stripped oils were supplemented with α‐tocopherol (500 mg kg^?1), δ‐tocopherol (500 mg kg^?1) or a mixture of α‐, β‐, γ‐ and δ‐tocopherols (250 mg kg^?1 each) and heated under the same conditions. Losses of tocopherols and formation of polymeric triacylglycerols were followed. Total polar compounds were also evaluated after 10 h of heating. Results demonstrated that tocopherols were lost very rapidly, in the expected order, with α‐tocopherol being the least stable. Polymeric and polar compound formation during heating was inhibited to a variable extent, being more dependent on the natural content and type of tocopherols than on the degree of unsaturation of the oil. For example, polymeric and polar compound contents in soybean oil were significantly lower than those found in high‐linoleic sunflower oil. However, the expected influence of the degree of unsaturation was evident when oils were unprotected or possessed identical initial antioxidant contents. Finally, levels of degradation compounds after 10 h of heating were not dependent on the remaining content of antioxidants. © 2002 Society of Chemical Industry