棕榈油基基料油相容性及结晶形态的研究

利用ΔSFC和等固曲线研究了棕榈油硬脂分提物(POs)、棕榈油中熔点分提产物(PMF)及棕榈仁油(PKO)三元混合体系的相容性,并采用偏光显微观察对混合体系的晶体形态进行研究。结果表明:在考察的整个温度区间内所有配方中均出现共晶现象,多数配方在15～25℃区间共晶现象最为严重,但d配方(POs-PMF-PKO,质量比为0.45∶0.45∶0.1)的相容性最好,结合偏光显微观察发现甘油三酯的组成对混合体系的晶形影响显著。     

巧克力涂层基料油的理化性质及其相容性研究

选用棕榈油中间分提物(PMF)、全氢化棕榈仁液油(HPKOL)、可可脂(CB)作为巧克力涂层的基料油,对其理化性质及其相容性进行分析。结果表明,当两相体系PMF-HPKOL中PMF含量在30%以下时,共晶现象较弱。PMF和HPKOL混合可以作为涂层油脂配方,用于开发无反式脂肪酸巧克力涂层。添加可可脂会导致三相体系(PMF-HPKOL-CB)严重的共晶现象,因此在代可可脂涂层配方中不宜再添加可可脂。     

马铃薯发酵乳饮料的研制

以马铃薯、牛奶为主要原料,利用乳酸菌发酵研制出马铃薯发酵乳饮料。通过单因素试验和正交试验对饮料的配方及稳定性进行探究,确定最佳的工艺参数与产品配方。以感官评分为评价指标,结果显示最佳工艺参数为:马铃薯浆与牛奶比例为6∶4(v/v),乳酸菌接种量4%(v/v),发酵温度41℃,发酵时间为20 h。以感官评分与沉淀率为评价指标,结果显示最佳产品配方为:蔗糖添加量8%(w/w),复合酸味剂(柠檬酸∶酒石酸=1∶2)添加量0.1%(w/w),复配稳定剂(琼脂∶果胶∶单甘酯=4∶1∶1)添加量为0.2%(w/w)。制得的马铃薯发酵乳饮料风味独特,口感细腻,酸甜可口。     

棕榈油硬脂和棕榈油中间分提物性能及相容性研究

为改善油脂可塑性和口溶性,及为开发以棕榈油产品为主要原料专用油脂产品提供理论依据,研究棕榈油硬脂(PSt)、棕榈油中间分提物(PMF)两者间相容性。测定二元混合体系固体脂肪含量(SFC)值,并通过计算其理论值与实测值之间差值△SFC,结合T–△SFC曲线、二元等温曲线等直观分析,结果表明:PSt与PMF混合物在25℃、PSt含量为30%～50%时,二者间偏晶现象严重;而在35℃～50℃时,二者间共晶现象较为严重;在0℃～10℃和30℃～35℃范围内,二者间具有较好相容性。     

巧克力涂层基料油理化性质和相容性的研究北大核心CSCD

选用棕榈油中间分提物(PMF)和氢化棕榈油(HPO)作为巧克力涂层的基料油,对两种油脂的理化性质进行了分析。同时,通过等温曲线和实测固体脂肪含量与理论固体脂肪含量的偏差曲线分析PMF和HPO的相容性。实验结果表明:PMF和HPO在脂肪酸和甘三酯的组成上相似,PMF和HPO具有良好的相容性,PMF和HPO按照比例3∶7(质量比)混合可以作为巧克力涂层基料油配方。     

巧克力涂层基料油理化性质和相容性的研究

选用棕榈油中间分提物(PMF)和氢化棕榈油(HPO)作为巧克力涂层的基料油,对两种油脂的理化性质进行了分析。同时,通过等温曲线和实测固体脂肪含量与理论固体脂肪含量的偏差曲线分析PMF和HPO的相容性。实验结果表明:PMF和HPO在脂肪酸和甘三酯的组成上相似,PMF和HPO具有良好的相容性,PMF和HPO按照比例3∶7(质量比)混合可以作为巧克力涂层基料油配方。     

棕榈油与棕榈油中熔点分提产物相容性及结晶形态研究

利用等温相图和偏光显微技术研究了棕榈油(PO)与棕榈油中熔点分提产物(PMF)在混合体系中的相容性及晶体形态.结果表明:PO与PMF混合体系在0～40℃相容性良好,仅在桌些温度范围内存在轻微的共晶/偏晶现象;结晶形态研究表明甘三酯组成对混合体系晶形有显著影响.     

西番莲饮料的加工工艺研究

确定了西番莲果汁饮料的生产工艺流程及工艺参数。通过L9(34)正交试验得出影响西番莲饮料品质的主次因素依次为:原果汁的添加量、稳定剂添加量、柠檬酸的添加量和白砂糖的添加量;西番莲饮料的最佳配方为:原汁添加量为10%、白砂糖的添加量为8%、柠檬酸的添加量为0.1%、稳定剂(CMC-Na∶黄原胶∶果胶∶琼脂=1∶1∶1∶1)的添加量为0.2%。     

棕榈油中间分提物(PMF)在冰淇淋中应用研究

通过对棕榈油中间分提物(PMF)理化性质分析,表明棕榈油中间分提物理化性质能满足生产冰淇淋要求,并用此特定油脂进行冰淇淋配方研究,确定PMF油基冰淇淋最佳配方:PMF添加量为6%、脱脂乳粉添加量为8%、糖添加量为13%、乳化剂添加量为0.5%、稳定剂添加量为0.2%。     

银杏香橙果冻的研制

研究以银杏和香橙为主要原料,以魔芋胶、卡拉胶、黄原胶三种胶混合作为凝胶主体制作银杏香橙果冻。采用凝胶情况和果冻成品的感官评价得分作为指标,研究银杏汁和橙汁配比、蔗糖添加量、苹果酸添加量、柠檬酸添加量以及复合胶的配比等对果冻产品的影响。进一步通过正交试验,确定银杏香橙果冻的最佳配方:银杏香橙混合汁添加量为50%、银杏汁和香橙汁的配比为1∶3(v/v)、蔗糖添加量为14%、复合胶添加量为1.2%(魔芋胶0.5%、黄原胶0.1%、卡拉胶0.6%)、混合酸添加量为0.2%(苹果酸0.1%、柠檬酸0.1%)。按照此配方制备的果冻结构均匀、口感细腻、酸甜可口,具有独特的银杏香橙风味。     

Physicochemical characteristics of soybean oil, palm kernel olein, and their binary blends

Soybean oil (SBO), palm kernel olein (PKO) and their binary blends (containing 5–40% PKO) were studied for their physicochemical characteristics. Decreases in band absorbencies of the resultant Fourier transform infrared spectra were observed in regions attributable to vibrations of the functional groups of unsaturated fatty acids, mainly the =C–H cis stretching at 3009 cm⁻¹and –C=C cis stretching at 1657 cm⁻¹. The solid fat content was measurable in the blends containing 15–40% PKO at 5 and 10 °C, ranging within 4–20% and 2–13%, respectively. The differential scanning calorimetry melting curve for SBO exhibited more complex transition peaks, suggesting a     polymorphic transformation when compared with PKO with a simpler     . Blending of SBO with PKO reduced the complexity caused by the polymorphic transformation, featuring the endotherms that only related to the β' fat crystals.     

Separation/fractionation of triglycerides in terms of fatty acid constituents in palm kernel oil using supercritical CO2

Separation of triglycerides in terms of fatty acid constituents in palm kernel oil (PKO) from dehulled ground palm kernel using supercritical carbon dioxide (SC‐CO₂) as a solvent at 40 and 80 °C and pressures of 20.7, 27.6, 34.5, 41.4 and 48.3 MPa was studied. The extraction was continuous and PKO was fractionated into four fractions. Triglycerides with differing fatty acid contents of caprylic (C8), capric (C10), lauric (C12), myristic (C14), palmitic (C16), stearic (C18:0), oleic (C18:1) and linoleic (C18:2) acid were separated in different percentages in different fractions. About 70% of PKO comprises triglycerides with C8–C12 fatty acids and these fatty acids were mostly extracted in fractions 1and 2. As a result, higher yields were observed in these fractions, especially at pressures higher than 27.6 MPa. The C16 and C18:2 components were extracted in fractions 3 and 4. These triglycerides form only a part of the remaining 30% of the fatty acid composition of PKO, hence the evidently diminishing yield in the later fractions. However, the compositions were found to be statistically significant for higher pressures and fraction times according to the type of fatty acid constituents. Copyright © 2006 Society of Chemical Industry     

Physicochemical properties and crystallisation behaviour of bakery shortening produced from stearin fraction of palm-based diacyglycerol blended with various vegetable oils

The stearin fraction of palm-based diacylglycerol (PDAGS) was produced from dry fractionation of palm-based diacylglycerol (PDAG). Bakery shortening blends were produced by mixing PDAGS with either palm mid fraction, PMF (PDAGS/PMF), palm olein, POL(PDAGS/POL) or sunflower oil, SFO (PDAGS/SFO) at PDAGS molar fraction of X_PDAGS = 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%. The physicochemical results obtained indicated that C16:0 and C18:1 were the dominant fatty acids for PDAGS/PMF and PDAGS/POL, while C18:1 and C18:2 were dominant in the PDAGS/SFO mixtures. SMP and SFC of the PDAGS were reduced with the addition of PMF, POL and SFO. Binary mixtures of PDAGS/PMF had better structural compatibility and full miscibility with each other. PDAGS/PMF and PDAGS/SFO crystallised in β′+β polymorphs in the presence of 0.4–0.5% PDAGS while PDAGS/POL resulted in β polymorphs crystal. The results gave indication that PDAGS: PMF at 50%:50% and 60%:40% (w/w) were the most suitable fat blend to be used as bakery shortening.     

三氯卡班/聚乳酸超细纤维的制备及抗菌性能

通过在聚乳酸纺丝中添加抗菌剂三氯卡班（TCC）,采用静电纺丝技术制备了一种具有抗菌活性的聚乳酸超细纤维,利用扫描电子显微镜（SEM）分析溶剂的组成及配比、TCC质量分数等对纤维微观形貌的影响。研究了掺入抗菌剂的量对抗菌性能的影响。结果表明:当纺丝液所用溶剂为二氯甲烷/聚乙二醇（400目）时TCC的溶解性及TCC/PLA的成丝情况均较好,所用溶剂配比为CH2Cl2:PEG(400)=9:1(V:V);当聚乳酸纺丝液中TCC的质量分数从0.1%增加到0.6%时,纤维形态分布基本保持不变,超细纤维的直径稍有增加;所用抗菌剂TCC质量分数为0.5%时,制得的抗菌纤维对金黄色葡萄球菌和大肠杆菌的抑菌率分别为98.6%和94.2%。     

Evaluation of high oleic-high stearic sunflower hard stearins for cocoa butter equivalent formulation

Cocoa butter equivalents (CBEs) are produced from vegetable fats by blending palm mid fraction (PMF) and tropical butters coming from shea, mango kernel or kokum fat. In this regard, high oleic-high stearic (HOHS) sunflower hard stearins from solvent fractionation can be used in CBE production since their compositions and physical properties are similar to those found in the above-mentioned tropical butters. In this work, three sunflower hard stearins (SHS) ranging from 65% to 95% of disaturated triacylglycerols and a shea stearin (used as reference) were blended with PMF to evaluate their potential use in CBEs formulation. Isosolid phase diagrams of mixtures of PMF/SHS showed eutectic formation for SHS 65 and SHS 80, but monotectic behaviour with softening effect for SHS 95. Three CBEs from SHS and shea stearin were formulated according to phase behaviour diagrams and solid fat content data at 25 °C. Isosolid phase diagrams of mixtures of these CBEs with cocoa butter showed no eutectic behaviour. Therefore, CBEs elaborated from SHS exhibited full compatibility with cocoa butter.     

不浸酸无铬多金属配合鞣液的改性及其应用工艺的优化

通过引入多种小分子有机酸配体与引入微量铬配体的方法对一定比例混合的锆-铝-钛多金属配合鞣液进行改性,当锆、铝、钛摩尔比一定、且按n(总无铬金属离子)∶n(乳酸)∶n(柠檬酸)=1∶0.1∶0.1进行有机蒙囿改性、按n(总无铬金属离子)∶n(铬金属)=1∶0.05进行改性时,鞣液具有高的浑浊pH与高的稳定性。选择浓度为2mol/L、pH为2.0的改性鞣液,用于不浸酸鞣制时所鞣革收缩温度可达到88.9℃。     

Oxidative stability of purified common Kilka (Clupeonella cultiventris caspia) oil as a function of the bene kernel and hull oils

Oxidative stability of the purified common Kilka triacylglycerols (PKO) as affected by 1–8% w/w of bene kernel (BKO) and hull (BHO) oils was studied and compared with that of 100 mg kg^?1 of BHT and α‐tocopherol. Lipid oxidation was measured by monitoring peroxide value till the minute 80 (PV₈₀, meq kg^?1) and also by determining the oxidative stability index at 60 °C (OSI₆₀, h). In the Rancimat test, the OSI₆₀ of the PKO (1.66 h) was significantly increased by some of the added antioxidants, and the BKO 8% (7.98 h) had the highest antioxidant activity with no significant differences among the BHT, α‐tocopherol and the BHO 8%. Furthermore, an exponential regression curve with a good coefficient of determination (R² > 0.94) was observed between the changes in the PV₈₀ and OSI₆₀ values of the PKO.     

复合乳化剂对椰奶稳定性的影响

本实验研究了复合乳化剂单苷酯-蔗糖酯（2∶1）质量分数对椰奶的油滴粒径、ζ-电位以及乳析指数的影响,为椰奶的加工生产提供理论依据。结果表明,当椰奶中加入的复合乳化剂质量分数在0.15%～0.45%之间时,椰奶的粒径为300～400 nm,且分散指数为0.2～0.4,说明粒径较小,且分布均匀;当复合乳化剂质量分数为0.25%～0.45%时,ζ电位在-40～-42 mV,油滴之间的排斥力较大,椰奶的稳定性较好。而根据乳析指数以及椰奶的上浮情况,复合乳化剂的质量分数在0.35%～0.45%的乳析指数均为3%左右,上浮很少,稳定性较好。综合考虑,复合稳定剂添加量0.25%为宜。     

Kinetics of 1,4-dioxane biodegradation by monooxygenase-expressing bacteria

1,4-Dioxane is a probable human carcinogen, and an important emerging water contaminant. In this study, the biodegradation of dioxane by 20 bacterial isolates was evaluated, and 13 were found to be capable of transforming dioxane. Dioxane served as a growth substrate for Pseudonocardia dioxanivorans CB1190 and Pseudonocardia benzenivorans B5, with yields of 0.09 g protein g dioxane(-1) and 0.03 g protein g dioxane(-1), respectively. Cometabolic transformation of dioxane was observed for monooxygenase-expressing strains that were induced with methane, propane, tetrahydrofuran, or toluene including Methylosinus trichosporium OB3b, Mycobacterium vaccae JOB5, Pseudonocardia K1, Pseudomonas mendocina KR1, Ralstonia pickettii PKO1, Burkholderia cepacia G4, and Rhodococcus RR1. Product toxicity resulted in incomplete dioxane degradation for many of the cometabolic reactions. Brief exposure to acetylene, a known monooxygenase inhibitor, prevented oxidation of dioxane in all cases, supporting the hypothesis that monooxygenase enzymes participated in the transformation of dioxane by these strains. Further, Escherichia coli TG1/pBS(Kan) containing recombinant plasmids derived from the toluene-2- and toluene-4-monooxygenases of G4, KR1 and PKO1 were also capable of cometabolic dioxane transformation. Dioxane oxidation rates measured at 50 mg/L ranged from 0.01 to 0.19 mg hr(-1) mg protein(-1) for the metabolic processes, 0.1-0.38 mg hr(-1) mg protein(-1) for cometabolism by the monooxygenase-induced strains, and 0.17-0.60 mg hr(-1) mg protein(-1) for the recombinant strains. Dioxane was not degraded by M. trichosporium OB3b expressing particulate methane monooxygenase, Pseudomonas putida mt-2 expressing a toluene side-chain monooxygenase, and PseudomonasJS150 and Pseudomonas putida F1 expressing toluene-2,3-dioxygenases. This is the first study to definitively show the role of monooxygenases in dioxane degradation using several independent lines of evidence and to describe the kinetics of metabolic and cometabolic dioxane degradation.