Thermal and crystal characteristics of enzymatically interesterified fats of fatty acid-balanced oil and fully hydrogenated soybean oil in supercritical CO2 system

Blends of fatty acid-balanced oil that was prepared by the aqueous enzymatic extraction, and with fully hydrogenated soybean oil in different weight ratios from 30:70 to 80:20 (wt%) were interesterified using Lipozyme RM IM in a supercritical CO₂ system. The optimal immobilized enzyme dosage, pressure, substrate ratio, temperature, and time were 6% (w/w) of initial substrates, 8 MPa, blend ratio with 60:40 (wt%) of fatty acid-balanced oil and fully hydrogenated soybean oil, a temperature of 70°C, and reaction time of 2 h, respectively. It was observed that at the optimal conditions, under supercritical CO₂ conditions, the reaction time of the interesterification was shorter than that of conventional enzymatic interesterification. The slip melting point, solid fat content, fatty acid composition, differential scanning calorimetry, polymorphic form and crystal morphology of the enzymatically interesterified fats were evaluated. The results indicated that the interesterified fats showed desirable physical properties with lower slip melting point and solid fat content, suitable crystal form (β′ polymorph), and without trans-fatty acid for possible use as a shortening and margarine stock.     

毛细管气相色谱法测定精炼和氢化大豆油中的反式脂肪酸

采用CP—Sil88强极性毛细管柱气相色谱法对精炼和氢化大豆油中的顺、反异构和位置异构的脂肪酸进行定性、定量分析。结果表明，精炼和氢化大豆油中主要顺、反式脂肪酸实现了很好地分离，各种位置异构的反式脂肪酸也实现了较好地分离。采用归一化法对各种脂肪酸进行定量分析，结果表明，精炼大豆油中反式脂肪酸为总脂肪酸含量的3．45％，以△9c，12t—C18：2、△9t，12c—C18：2和△9c，12c，15t—C18：3、△9t，12c，15c—C18：3 4种形式为主；氢化大豆油中反式脂肪酸为总脂肪酸含量的38．73％，以△9t—C18：1、△10t—C18：1、△11t—C18：1 3种形式为主的反式十八碳单烯酸（t—C18：1）占反式脂肪酸总量的90．81％。     

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.     

在加工油脂产品中消除反式脂肪酸的应用实践

在部分氢化油脂或选择性氢化油脂中,反式脂肪酸的含量相对最高;而氢化工艺能赋予油脂一系列的优良特性,如快速结晶等.科学研究证明,反式脂肪酸对健康有副作用.食品制造商面临来自消费者、零售商以及法规部门的愈来愈强烈的压力,要求在加工食品中消除反式脂肪酸.但在实际应用时,不含反式脂肪酸的替代油脂与部分氢化油脂中的固体脂肪含量(SFC)特征相似,从而带来结晶速度慢、产能下降、成本上升等问题.目前对于在食品中消除反式脂肪酸在技术上已经有一些解决方案,同时开发出一系列新型的能够促进油脂结晶的复合乳化剂产品;许多油脂和焙烤食品制造商用不含反式脂肪酸的分馏棕榈油和交酯化棕榈油、取代了含大量反式脂肪酸的部分氢化油,而新型复合乳化剂解决了结晶速度这一难题.这些新型复合乳化剂产品是专为促进油脂的快速结晶而开发的,可帮助企业生产线的效率优化,并改善油脂在油酥类糕点、蛋糕以及脂基夹心等焙烤食品中的应用性能.     

在加工油脂产品中消除反式脂肪酸的应用实践

在部分氢化油脂或选择性氢化油脂中,反式脂肪酸的含量相对最高;而氢化工艺能赋予油脂一系列的优良特性,如快速结晶等.科学研究证明,反式脂肪酸对健康有副作用.食品制造商面临来自消费者、零售商以及法规部门的愈来愈强烈的压力,要求在加工食品中消除反式脂肪酸.但在实际应用时,不含反式脂肪酸的替代油脂与部分氢化油脂中的固体脂肪含量(SFC)特征相似,从而带来结晶速度慢、产能下降、成本上升等问题.目前对于在食品中消除反式脂肪酸在技术上已经有一些解决方案,同时开发出一系列新型的能够促进油脂结晶的复合乳化剂产品;许多油脂和焙烤食品制造商用不含反式脂肪酸的分馏棕榈油和交酯化棕榈油、取代了含大量反式脂肪酸的部分氢化油,而新型复合乳化剂解决了结晶速度这一难题.这些新型复合乳化剂产品是专为促进油脂的快速结晶而开发的,可帮助企业生产线的效率优化,并改善油脂在油酥类糕点、蛋糕以及脂基夹心等焙烤食品中的应用性能.     

两种Pricat镍催化剂对大豆油氢化中固脂和反式酸含量的影响

研究了两种Prieat镍催化刺在大豆油氢化过程中对固脂和反式酸含量的影响。结果表明，9908型催化荆适合油脂的选择性氢化，而9910型则适合植物油的极度氢化。详细探讨了9908型催化刺在不同氢化温度、氢气压力以及催化荆浓度下对氢化油固体脂肪含量以及反式脂肪酸的影响。结果表明，温度对氢化反应的异构化影响较大，氢气压力和催化剂浓度对异构化的影响相对较小。     

An investigation on the physicochemical characterization of interesterified blends of fully hydrogenated palm olein and soybean oil

In this study, the effect of interesterification (using sodium methoxide) on physicochemical characteristics of fully hydrogenated palm olein (FHPO)/soybean oil blends (10 ratios) was investigated. Interesterification changed free fatty acid content, decreased oil stability index, solid fat content (SFC) and slip melting point (SMP), and does not affected the peroxide value. With the increase of FHPO ratio, oil stability index, SFC and SMP increased in both the interesterified and non-interesterified blends. Fats with higher FHPO ratio had narrower plastic range, as well. Compared to the initial blends, interesterified fats had wider plastic ranges at lower temperatures. Both the non-interesterified and interesterified blends showed monotectic behavior. The Gompertz function could describe SFC curve (as a function of temperature, saturated fatty acid (SFA) content or both) and SMP (as a function of SFA) of the interesterified fats with high R² and low mean absolute error.     

棉籽油硬脂和全氢化棉籽油硬脂的组成、热性质和微观结构分析

为扩大棉籽油用途,提高其附加值,采用气相色谱、高效液相色谱、低场脉冲核磁共振分析仪、差示扫描量热仪、X-射线衍射仪和偏光显微镜分析了棉籽油改性后的产物棉籽油硬脂(COS)和全氢化棉籽油硬脂(FHCOS)的脂肪酸组成、甘三酯组成、SFC含量、热性质和微观结构。结果表明：COS主要由不饱和脂肪酸和非三饱和的甘三酯组成,FHCOS几乎全部由饱和脂肪酸和三饱和甘三酯组成;随温度升高,COS的SFC不断降低,FHCOS的SFC在温度高于35℃时开始降低,相同温度下FHCOS的固体脂肪含量(SFC)均高于COS的,COS在结晶和熔化过程中均有2个峰,FHCOS有1个峰,FHCOS的熔化和结晶温度均高于COS的;COS在15℃时无明确的晶型及稳定的结构,FHCOS为二倍链长堆积的β′晶型,结晶体为针状或棒状,结晶聚集体为类似玫瑰花状。因此,以COS和FHCOS代替棕榈油作为生产起酥油、人造奶油、黄油等的基料油具有一定的开发和应用前景。     

Enzymatic synthesis of structured lipids from liquid and fully hydrogenated high oleic sunflower oil

Structured lipids (SL) were synthesized via enzymatic (EI) and chemical interesterification of high oleic sunflower oil (SO) and fully hydrogenated high oleic SO with Lipozyme TL IM (Thermomyces lanuginose) for 3 h at 70°C, 300 rpm. Reaction showed changes in the triacylglycerols (TAGs) composition, solid fat content (SFC), thermal behavior, regiospecific distribution, microstructure, and polymorphism. Results revealed that the EI caused considerable rearrangement of the TAG species with lower levels of tri-saturated and tri-unsaturated TAG and higher levels of monoun- and diunsaturated TAG. The interesterified blends showed reduced SFC between 20 and 35°C, lowering the melting point. After 3-h incubation, EI produced acyl migration to some extent. The SL showed the required characteristics for application as bakery fats and as additives for lipid crystallization in the food industry.     

以樟树籽仁油、油茶籽油、全氢化棕榈油 为原料的起酥油基料油的表征

采用专一性脂肪酶Lipozyme TL IM,将樟树籽仁油、油茶籽油和全氢化棕榈油按4个质量比(2∶2∶4, 2∶2∶5, 2∶2∶6, 2∶2∶7)进行sn-1,3位随机酯交换制备起酥油基料油,以物理混合物(PB)为对照对酯交换反应后产品(IP)的脂肪酸组成及熔点、多晶形式、微观结构、甘油三酯(TAG)的组成进行测定。结果表明:酯交换反应后仍有12.21%～16.91%的中链脂肪酸(MCFA)被保留;从DSC熔融曲线发现,相较于PB, IP只产生了一个响应值较弱的峰形,SFC曲线则表现一直陡峭下降的趋势,具有狭窄的塑性范围,是理想的高稳定起酥油基料油;微观结构上表现为更小(约20μm)球状晶体;IP中生成了新型的TAG种类(CPO, LaOP, LaPP, COS, CPS等)。总体而言,合成的起酥油基料油在能保证正常膳食长链脂肪酸(LCFA)摄入的同时,还能提供一定量MCFA的摄入,被人体快速吸收,具有一定的营养功能。     

Preparation of specialty fats from beef tallow and canola oil by chemical interesterification: physico-chemical properties and bread applications of the products

Blends of beef tallow (BT)/canola oil (CO) (85:15, 65:35, w/w) were interesterified under the following conditions: 0.4% CH₃ONa, 60 °C, 30 min. Triacylglycerol (TAG) composition, polymorphic forms, crystal morphology, thermal properties, rheological properties and oxidative stability of the original and interesterified blends were evaluated. Chemical interesterification (CIE) caused a more balanced rearrangement of TAG species, reduction of trisaturated (S₃), triunsaturated (U₃) TAG content and increase in monosaturate-diunsaturated (SU₂) TAG content. X-ray diffraction (XRD) revealed that all the interesterified blends were exclusively double chain (2L) stacking β′ crystal. Thermal curves confirmed slight narrow melting and crystallization temperature ranges appearing in interesterified blends, mainly due to decreased S₃ and U₃ type TAGs and increased SU₂ after CIE. Rheological analysis showed that CIE led to dropping in both hardness, storage modulus (G′) and loss modulus (G″) of BT/CO blends. The oxidative stability of the interesterified fats, which was reduced compared with the substrate blends, was significantly improved using 0.02% TBHQ. A shortening and a margarine, both containing low trans were prepared by interesterified BT/CO 85:15, 65:35 blends, respectively, which were crystallized in a votator and tested in bread baking. The results of instrumental and sensory analyses showed similar acceptability of the two types of breads. The present study suggests that the interesterified fats fulfill the requirements of marketable bakery shortenings and margarines, respectively.     

脂酶催化下大豆粉末磷脂与全氢化大豆油酯交换反应的研究

本文利用脂酶的特异性催化作用,研究了正己烷体系中,大豆粉末磷脂与全氢化大豆油的酯交换反应。利用碘值和产率为指标,考察了酶的种类及用量、底物摩尔比、温度、时间等因素对酯交换反应的影响,通过单因素和正交试验优化了大豆粉末磷脂与全氢化大豆油酯交换反应条件。发现在25%磷脂酶A1(以磷脂质量为基准)催化下,摩尔比4:1的全氢化大豆油和大豆粉末磷脂的正己烷溶液(磷脂浓度为0.20 g/mL),在50 ℃下反应24 h,得到产率为72.9%的改性磷脂。与原料磷脂相比,改性磷脂的碘值由89 g /100 g降至52 g /100 g,脂肪酸组成变化较大,硬脂酸含量约为原料磷脂的9倍,不饱和脂肪酸亚麻酸和亚油酸含量降低了约一半,实现了大豆粉末磷脂的结构修饰。     

大豆油脚浸出油制备生物柴油及性能研究

大豆油脚浸出油与甲醇在催化剂KOH作用下通过酯交换反应制得生物柴油(BDF)。用气相色谱法跟踪研究醇油摩尔比、反应温度、反应时间及催化剂用量对产物生物柴油浓度的影响,正交实验得到大豆油脚浸出油制备生物柴油最佳工艺条件为:反应温度45℃、催化剂用量1%、醇油摩尔比6∶1、反应时间45 min,生物柴油含量为96.8%。生物柴油的主要性能指标符合0#柴油标准(GB 252-1994)。考察了大豆油脚浸出油酯交换反应的动力学,由实验数据绘制的动力学曲线呈现出酯交换反应在开始阶段为二级反应,并逐步转变为一级反应,反应后期为零级反应。由动力学实验数据求出酯交换反应的动力学参数,酯交换反应的活化能为47.71 kJ/mol,频率因子为6.01×107L/(mol.min)。     

Influence of chemical interesterification on thermal behavior,microstructure, polymorphism and crystallization properties of canola oil and fully hydrogenated cottonseed oil blends

This work evaluated chemical interesterification of canola oil (CaO) and fully hydrogenated cottonseed oil (FHCSO) blends, with 20%, 25%, 30%, 35% and 40% (w/w) FHCSO content. Interesterification produced reduction of trisaturated and increase in monounsaturated and diunsaturated triacylglycerols contents, which caused important changes in temperatures and enthalpies associated with the crystallization and melting thermograms. It was verified reduction in medium crystal diameter in all blends, in addition crystal morphology modification. Crystallization kinetics revealed that crystal formation induction period and maximum solid fat content were altered according to FHCSO content in original blends and as a result of random rearrangement. Changes in Avrami constant (k) and exponent (n) indicated, respectively, that interesterification decreased crystallization rates and altered crystalline morphology. However, X-ray diffraction analyses showed randomization did not change the original crystalline polymorphism. The original and interesterified blends had significant predominance of β′ polymorph, which is interesting for several food applications.     

Lipase-catalysed interesterification between canola oil and fully hydrogenated canola oil in contact with supercritical carbon dioxide

The processing parameters in enzymatic reactions using CO₂-expanded (CX) lipids have strong effects on the physical properties of liquid phase, degree of interesterification, and physicochemical properties of the final reaction products. CX-canola oil and fully hydrogenated canola oil (FHCO) were interesterified using Lipozyme TL IM in a high pressure stirred batch reactor. The effects of immobilised enzyme load, pressure, substrate ratio and reaction time on the formation of mixed triacylglycerols (TG) from trisaturated and triunsaturated TG were investigated. The optimal immobilised enzyme load, pressure, substrate ratio and time for the degree of interesterification to reach the highest equilibrium state were 6% (w/v) of initial substrates, 10 MPa, blend with 30% (w/w) of FHCO and 2 h, respectively. The physicochemical properties of the initial blend and interesterified products with different FHCO ratios obtained at optimal reaction conditions were determined in terms of TG composition, thermal behaviour and solid fat content (SFC). The amounts of saturated and triunsaturated TG decreased while the amounts of mixed TG increased as a result of interesterification. Thus, the interesterified product had a lower melting point, and broader melting and plasticity ranges compared to the initial blends. These findings are important for better understanding of CX-lipid reactions and for optimal formulation of base-stocks of margarine and confectionary fats to meet industry demands.     

PVC密封圈中环氧大豆油向食品模拟物迁移量的测定

建立了气相色谱-质谱法(GC-MS)对食品玻璃包装瓶盖聚氯乙烯(Polyvinyl chloride polymer,PVC)密封圈中环氧大豆油(Epoxidized soybean oil,ESBO)向食品模拟物迁移量的检测方法。以蒸馏水和橄榄油为模拟物,在40℃条件下浸泡瓶盖240h,经甲酯化和衍生化,以11,14-二环氧二十烷酸乙酯为内标物,通过测定环氧亚油酸(18∶2 2E)衍生物的含量,进而定量测定ESBO的迁移量。结果表明:ESBO在0.5~50.0mg/kg的浓度范围内线性关系好,R2大于0.993,回收率在92.8%~103.9%之间,RSD为0.9%~8.0%(n=6),检出限(LOD)为0.2mg/kg,定量限(LOQ)为0.5mg/kg,方法精密度好,灵敏度高,定性定量准确。最后,应用其对24种不同PVC密封圈中的ESBO迁移量进行测定,水基模拟物中ESBO的迁移量符合法规EC 10/2011限量,而在油脂模拟物中测得含量在0.7~501.8mg/kg之间,其中7种超过了限量要求。     

PVC密封圈中环氧大豆油向食品模拟物迁移量的测定

建立了气相色谱-质谱法（GC-MS）对食品玻璃包装瓶盖聚氯乙烯（Polyvinyl chloride polymer,PVC）密封圈中环氧大豆油（Epoxidized soybean oil,ESBO）向食品模拟物迁移量的检测方法。以蒸馏水和橄榄油为模拟物,在40℃条件下浸泡瓶盖240h,经甲酯化和衍生化,以11,14-二环氧二十烷酸乙酯为内标物,通过测定环氧亚油酸（18∶2 2E）衍生物的含量,进而定量测定ESBO的迁移量。结果表明:ESBO在0.5⁵0.0mg/kg的浓度范围内线性关系好,R2大于0.993,回收率在92.8%¹03.9%之间,RSD为0.9%⁸.0%（n=6）,检出限（LOD）为0.2mg/kg,定量限（LOQ）为0.5mg/kg,方法精密度好,灵敏度高,定性定量准确。最后,应用其对24种不同PVC密封圈中的ESBO迁移量进行测定,水基模拟物中ESBO的迁移量符合法规EC 10/2011限量,而在油脂模拟物中测得含量在0.7⁵01.8mg/kg之间,其中7种超过了限量要求。      

Characterisation of zero‐trans margarine fats produced from camellia seed oil,palm stearin and coconut oil using enzymatic interesterification strategy

Zero‐trans interesterified fats were produced from camellia seed oil (CSO), palm stearin (PS) and coconut oil (CO) with three weight ratios (CSO/PS/CO, 50:50:10, 40:60:10 and 30:70:10) using Lipozyme TL IM. Results showed that the interesterified products contained palmitic acid (34.28–42.96%), stearic acid (3.96–4.72%), oleic acid (38.73–47.95%), linoleic acid (5.92–6.36%) and total medium‐chain fatty acids (MCFA)s (∑MCFAs, 5.03–5.50%). Compared with physical blends, triacylglycerols of OOO and PPP were decreased and formed new peaks of equivalent carbon number (ECN) 44 in the interesterified products. The product CPC3′ showed a slip melting point of 36.8 °C and a wide plastic range of solid fat content (SFC) (45.8–0.4%) at 20–40 °C. Also, the major β′ form was determined. These data indicated that the zero‐trans interesterified fats would have a potential functionality for margarine fats. Subsequently, the antioxidative stabilities of interesterified products with the addition of α‐tocopherol (α‐TOH) and ascorbyl palmitate (AP) were investigated. The results indicated that AP had a dose‐dependent effect at concentrations of 100, 200 and 400 ppm.     

Physico-chemical properties and food utilization possibilities of RF-treated mustard seed

Yellow mustard seed was treated by radio frequency (RF) heating for inactivation of myrosine enzyme, which is responsible for its pungency. The treated mustard seed was milled by an Alpine mill to <315 μm particle size and analysed for fatty acid, amino acid and techno-functional properties. The pungency of mustard seed flour was checked according to its sensory property. By use of RF-treated mustard seed, flour pork liver paste and mayonnaise were produced. The liver paste was qualified by its sensory property. The mayonnaise was investigated for sensory property, emulsion stability and consistency. Due to RF treatment the mustard seed became free of pungent flavour without significant changes in fatty acid and amino acid content. The fat binding ability and nitrogen solubility index of RF-treated mustard seed flour decreased a little bit. However, the emulsifying activity did not change, the emulsion stability of treated mustard seed flour was slightly higher than that of raw mustard seed flour. The sensory property of liver paste containing 1.5% (w/w) RF-treated mustard seed flour was the same as the sample without mustard (control). The sensory property, emulsion stability and consistency of mayonnaise containing 25% RF-treated mustard seed flour were better than that of control. By replacing yolk powder in mayonnaise with 50% RF-treated mustard seed flour, the sensory property and consistency of product decreased a little bit as compared to the control, but the emulsion stability did not change significantly.     

大豆低聚肽的功能性质及其应用

<正> 近年来,国内外对肽类物质的营养及其功能性质进行了大量研究。结果表明,在动物体内低聚肽比蛋白质更易消化,吸收速度也快于氨基酸。此外,低聚肽无沦是酪蛋白肽还是大豆肽,都表现出不同的生理活性,如具有ACEI(血管紧张素转化酶抑制剂)活性,即降血压作用、抗氧化作用、促进发酵作用及脂肪代谢作用等。目前,国内对大豆低聚肽的单一功能研究较多,但有系统的研究较