大豆卵磷脂的生产及其在食品中的应用

大豆油是我国主要食用油脂之一。毛大豆油中一般含有1.1～3.2％(一般约为1.8％左右)大豆磷脂,经水化脱胶,即可从毛油中分离出磷脂,精制后得到大豆卵磷脂。大豆卵磷脂包括磷脂、植物甘油类脂化合物、甘油三酸酯、甾醇、生育酚、游离脂肪酸等,其中磷脂化合物的组成是:磷脂酰胆碱(PC)15％、磷脂酰乙醇胺(PE)13％,磷脂酰肌醇(PI)9％、磷脂酸(PA)5％、磷脂酰丝氨酸(PS)2％。     

国际粮油近讯

<正> 大豆磷脂系精炼大豆油脱胶时副产品,若以2％含量计,日本现有油厂约有1.34万吨生产能力,但实际上全日本仅有6～7家公司生产大豆磷脂、每年回收磷脂约1万吨左右。大豆磷脂制品主要以磷脂酰胆碱(PC)含量为分,包括从15％含量粗制糊状品至98％以上高纯度粉末状精制品。日本工业生产大多为粗制磷脂,主要作食品乳化剂之用,日本年需求量予计约7000～8000吨,其余绝大部份直接作饲料添加剂。大豆磷脂系由磷脂酰胆碱(PC),磷脂酰乙醇胺(PE),磷脂酰肌醇(PI)和磷脂酸(PA)为主成份组成磷脂质混合物。其结构含有疏水性脂肪酸基和亲水性磷酸酯基,PI和PA具有阴离子,而PC与PE     

大豆混合油中磷脂反相胶束分子量分布的测定

用截留分子量为1、2、10、20万的无机陶瓷膜超滤浓度为24.7%(W/W)的大豆混合油,测定了不同膜管截留分子量在不同超滤温度的磷脂截留率.超滤温度为50℃时,截留分子量1万的膜对磷脂的截留率为98.3%.分析了大豆混合油中磷脂反相胶束的分子量分布和温度的关系.温度越高,磷脂反相胶束的分子量越大,越有利于超滤脱胶的进行.     

响应面法优化新型磷脂酶PLC＿MED193大豆油脱胶工艺的研究

利用大肠杆菌工程菌制备大量重磷脂PLC＿MED₁₉₃,将其应用于大豆毛油的脱胶过程中,在单因素试验的基础上采用响应面试验,得出磷脂酶用于大豆毛油脱胶的最佳工艺条件,即脱胶温度60℃、加酶量300 U/kg、脱胶pH 5.6、加水量3.0 mL、脱胶时间6 h,在此条件下,脱胶后大豆油的磷含量从36.75 mg/kg降低至(5.25±0.03)mg/kg,磷脂酰胆碱PC和磷脂酰乙醇胺PE含量降低至23 mg/g和20 mg/g,满足后续油脂精炼要求。     

水化脱胶工艺对大豆浓缩磷脂色泽品质的影响

研究了水化脱胶工艺对制备大豆浓缩磷脂品质的影响,同时研究了脱胶工艺对脱胶油酸价以及磷脂脱除率的影响。通过正交试验得到了最优工艺参数:水化温度60℃,加水量2.0％,水化时间30min。在此工艺条件下得到的浓缩磷脂Gardner色泽为8,可以在食品领域中应用。     

不同磷脂成分的研究及其乳化能力的比较

目的:对不同磷脂的组成成分和脂肪酸比例进行研究,比较不同磷脂在乳剂中的乳化能力。方法:采用《中国药典》中蛋黄卵磷脂(供注射用)的磷脂酰胆碱、磷脂酰乙醇胺和有关物质含量的测定方法,分别测定大豆卵磷脂、蛋黄卵磷脂以及蛋黄磷脂酰胆碱中的磷脂酰胆碱(PC)、磷脂酰乙醇胺(PE)、溶血磷脂酰胆碱(LPC)、溶血磷脂酰乙醇胺(LPE)、磷脂酰肌醇(PI)、鞘磷脂(SM)的含量;采用气相色谱法对大豆卵磷脂、蛋黄卵磷脂、蛋黄磷脂酰胆碱中主要的脂肪酸进行含量测定;分别采用大豆卵磷脂、蛋黄卵磷脂和蛋黄磷脂酰胆碱作为乳化剂进行脂肪乳的制备,以脂肪乳的平均粒径、粒径分布、D_(90)值、ζ电位和表面张力作为考察指标,对3种不同磷脂的乳化能力进行综合评价。结果:大豆卵磷脂、蛋黄卵磷脂、蛋黄磷脂酰胆碱中成分组成,脂肪酸组成及比例均有明显差异;采用大豆卵磷脂、蛋黄卵磷脂、蛋黄磷脂酰胆碱作为乳化剂制备的乳剂的物理稳定性也有显著差异。结论:大豆卵磷脂、蛋黄卵磷脂以及蛋黄磷脂酰胆碱由于其来源和制备工艺不同,使得其各自的成分和脂肪酸组成不一致,组成成分和脂肪酸的差异进一步导致了其乳化能力有所差异。     

储存受损害大豆的磷脂成分变化的高效液相色谱分析

大豆在储运中因湿度和温度过高而受损害后，磷脂组份发生较大的化学变化，高效液相色谱分析表明，不可皂化部分（主要是甾醇）和磷脂酸（ＰＡ）含量增加，而主要磷脂成分磷脂酰乙醇胺（ＰＥ）、磷脂酰肌醇（ＰＩ）、磷脂酰胆碱（ＰＣ）含量减少。受损害大豆毛油水化脱胶困难及脱后油中磷含量偏高均与磷脂组份发生化学变化有关。     

高品质大豆浓缩磷脂的制备

饲料级大豆浓缩磷脂与正己烷混合经离心除杂、无机陶瓷膜过滤、过氧化氢脱色等步骤可以制备得到高品质磷脂,制备过程中无机陶瓷膜孔径应选择20 nm以下,过氧化氢脱色过程应在真空条件下进行,温度不宜过高,在50℃,过氧化氢(浓度30%)用量1%和2%条件下制备的大豆浓缩磷脂色泽浅、透明度高、过氧化值低,性能接近于食品级大豆浓缩磷脂。     

无机陶瓷膜超滤大豆混合油脱胶的研究

用截留分子量1万的无机陶瓷膜在45℃、0.15 MPa下超滤大豆混合油,研究了膜通量与浓缩比的关系.超滤脱胶结果表明,超滤可以脱除95.78%的大豆磷脂,同时超滤脱胶油的色泽和毛油色泽相比,明显变浅,但是酸值升高.超滤还可以截留大豆油中的Ca、Mg、Fe和Cu等金属元素.     

冷冻结晶法纯化制备高纯度磷脂酰乙醇胺

为解决工厂低磷脂酰胆碱(PC)含量大豆粉末磷脂的积压问题,以及获得高纯度的磷脂酰乙醇胺(PE),以用碱性乙醇从低PC含量大豆粉末磷脂中提取的粗PE产品为原料,通过冷冻结晶法纯化制备高纯度PE。在单因素实验的基础上,以PE含量为指标,通过响应面实验对冷冻结晶纯化条件进行了优化。结果表明,PE的最佳冷冻结晶纯化条件为：料液比1∶40,冷冻时间21.5 h,冷冻温度-25℃,乙醇体积分数94%,乙醇碱浓度为94%乙醇与25%氨水体积比100∶8。在最佳条件下,产品PE含量为76.56%,PE回收率为81.25%。因此,冷冻结晶法纯化工艺可用于制备高纯度PE。     

卵磷脂类保健食品中PE、PC的高效液相色谱测定

为准确快速地对卵磷脂保健食品中有效成分进行定量分析 ,我们建立了卵磷脂保健食品中磷脂主要组分磷脂酰胆碱 (PC)、磷脂酰乙醇胺 (PE)的高效液相色谱测定方法。方法的日间精密度为 5 4 %～ 9 0 %;PE、PC的加标回收率分别为 83 0 %～ 10 5 6 %和 81 3%～ 86 0 %,均可满足卫生分析的要求。对 5种卵磷脂保健食品中的PC、PE的含量进行了测定 ,PC、PE的含量分别为15 2 %～ 2 4 2 %和 3 1%～ 6 1%。方法的样品前处理方法简单 ,且检测灵敏度高 ,分析速度快 ,适于在国内推广使用     

蛋黄卵磷脂的制备研究

研究了鸡蛋卵黄卵磷脂的制备工艺和产品质量分析。结果表明,使用95%乙醇分三次提取粗卵磷脂效果最佳,可制得卵磷脂含量约为70%的粗卵磷脂,得率约为10%;进一步使用ZnCl2沉淀制备卵磷脂效果最佳,使用10% ZnCl2纯化粗卵磷脂的回收率约为80%,产品中卵磷脂含量达94.25%;薄层层析结果表明,卵磷脂产品只有两个明显的斑点,分别为PC及PE两种成分。分光光度法测得卵磷脂的紫外最大吸收峰在215nm波长处。     

Isolation and characterization of lecithin from squid (Todarodes pacificus) viscera deoiled by supercritical carbon dioxide extraction

Marine lecithin was isolated and characterized from squid (Todarodes pacificus) viscera residues deoiled by supercritical carbon dioxide (SC-CO(2)) extraction. SC-CO(2) extraction was carried out to extract the oil from squid viscera at different temperatures (35 to 45 °C) and pressures (15 to 25 MPa). The extraction yield was higher at highest temperature and pressure. The major phospholipids of squid viscera lecithin were quantified by high-performance liquid chromatography (HPLC). Phosphatidylcholine (PC; 80.5% ± 0.7%) and phosphatidylethanolamine (PE; 13.2% ± 0.2%) were the main phospholipids. Thin layer chromatography (TLC) was performed to purify the individual phospholipids. The fatty acid compositions of lecithin, PC and PE were analyzed by gas chromatography (GC). A significant amount of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were present in both phospholipids of PC and PE. Emulsions of lecithin in water were prepared through the use of a homogenizer. The oxidative stability of squid viscera lecithin was high in spite of its high concentration of long-chain polyunsaturated fatty acids. PRACTICAL APPLICATION: Squid viscera are discarded as a waste by fish processing industry. Since lecithin from squid viscera contains higher amounts of polyunsaturated fatty acids, it may have promising effect to use in food, pharmaceutical, and cosmetic industries.     

Characterization of lecithin isolated from anchovy (Engraulis japonica) residues deoiled by supercritical carbon dioxide and organic solvent extraction

Lecithin was isolated and characterized from anchovy (Engraulis japonica) deoiled residues using supercritical carbon dioxide (SC-CO(2)) at a semibatch flow extraction process and an organic solvent (hexane) extraction. SC-CO(2) extraction was carried out to extract oil from anchovy at different temperatures (35 to 45 °C) and pressures (15 to 25 MPa). Extraction yield of oil was influenced by physical properties of SC-CO(2) with temperature and pressure changes. The major phospholipids of anchovy lecithin were quantitatively analyzed by high-performance liquid chromatography. Phosphatidylcholine (PC) (68%± 1.00%) and phosphatidylethanolamine (PE) (29%± 0.50%) were the main phospholipids. Thin layer chromatography was performed to purify the individual phospholipids. The fatty acid compositions of lecithin, PC, and PE were analyzed by gas chromatography. A significant amount of eicosapentaenoic acid and docosahexaenoic acid were present in both phospholipids of PC and PE. Emulsions of lecithin in water were prepared through the use of a homogenizer. Oxidative stability of anchovy lecithin was high in spite of its high concentration of long-chain polyunsaturated fatty acids. PRACTICAL APPLICATION: Lecithin can be totally metabolized by humans, so is well tolerated by humans and nontoxic when ingested. Lecithin from anchovy contain higher amounts of ω-3 fatty acids especially EPA and DHA, it may have positive outcome to use in food and pharmaceutical industries.     

Short communication: Effects of dietary deoiled soy lecithin supplementation on circulating choline and choline metabolites,and the plasma phospholipid profile in Holstein cows fed palm fat

Dietary lecithin is a source of choline. Our objective was to evaluate the effects of dietary deoiled soy lecithin feeding on circulating choline, choline metabolites, and the plasma phospholipid profile in lactating dairy cows fed fractionated palm fatty acids. In a split-plot Latin square design, 16 Holstein cows (160 ± 7 d in milk; 3.6 ± 1.2 parity) were randomly allocated to a main plot receiving a corn silage and alfalfa haylage-based diet with palm fat containing either moderate or high palmitic acid content at 1.75% of ration dry matter (moderate and high palmitic acid containing 72 or 99% palmitic acid in fat supplement, respectively; n = 8/palm fat diet). Within each palm fat group, deoiled soy lecithin was top-dressed at 0, 0.12, 0.24, or 0.36% of ration dry matter in a replicated 4 × 4 Latin square design with 14-d experimental periods. A 14-d covariate period was used to acclimate cows to palm fat feeding without lecithin supplementation. Blood sampling occurred during the final 3 d of each experimental period. Plasma choline and choline metabolites were quantified using liquid chromatography and mass spectrometry. Plasma phospholipids were profiled using time-of-flight mass spectrometry. Whereas no effects of treatments were detected for plasma choline or methionine, lecithin feeding increased the plasma concentrations of choline metabolites trimethylamine N-oxide and dimethylglycine (24 and 11%, respectively). Plasma phosphatidylcholine (PC) and sphingomyelin (SM) concentrations increased with deoiled lecithin feeding (e.g., PC 16:0/22:6 and SM d18:1/18:3). Lecithin supplementation also increased plasma lysophosphatidylcholine (LPC) concentrations (e.g., LPC 18:0) while reducing plasma phosphatidylethanolamine (PE) concentrations (e.g., PE 16:0/20:5). Although increases in microbial-derived trimethylamine N-oxide suggest gastrointestinal lecithin degradation, elevations in plasma dimethylglycine, PC, LPC, and SM suggest that choline availability was improved by lecithin feeding in cows, thus supporting enhanced endogenous phospholipid synthesis.     

苦味酸-氧化羧甲基纤维素酯的制备及其对尿素和肌酐的吸附性能

以羧甲基纤维素钠为原料,高碘酸钠为选择性氧化剂,在酸性条件下制备氧化的羧甲基纤维素。再将氧化的羧甲基纤维素6位的羧基进行酰化,与苦味酸反应制备复合型靶向口服吸附剂苦味酸-氧化羧甲基纤维素酯。通过XRD、FTIR、元素分析及化学官能团测定(碱熔法测醛基含量)等方法对苦味酸-氧化羧甲基纤维素酯的结构进行表征,结果表明苦味酸-氧化羧甲基纤维素酯已生成;在模拟人体生理介质的条件下,测定苦味酸-氧化羧甲基纤维素酯对尿素和肌酐的吸附性能,对尿素和肌酐的吸附平衡时间分别为10h和6h,醛基含量为75.23%。对尿素和肌酐的饱和吸附容量分别为16.08mg/g和2.10mg/g。尿素在氧化CMC-PA上的吸附等温线均符合Freundich方程,说明主要为化学吸附且吸附指数(1/n)小于2,表明吸附为"优惠吸附"。     

Recovered Camellia oleifera lecithin by acid and enzymatic oil-degumming: chemical composition and emulsifying properties

In this study, the chemical composition and emulsifying properties of camellia lecithin recovered from crude camellia oil by both acid and enzymatic degumming were investigated. Camellia lecithin recovered from acid degumming (CLAD) mainly comprised phospholipids (PS, PI, PE and PA), whereas camellia lecithin recovered from enzymatic degumming (CLED) contained more lysophospholipids (LPI, LPE, LPA). The saturated fatty acids made up a large portion of total fatty acids in CLED compared to CLAD. CLED-stabilised emulsions tended to be more stable than CLAD-stabilised emulsions. Meanwhile, emulsions stabilised by CLED exhibited smaller particle size in agreement with their microstructures. Moreover, both CLED and CLAD-stabilised emulsions were sensitive to pH and ionic strength changes and provided smaller particle size and higher stability at pH = 7 and 1 mm NaCl concentration. These findings provide valuable information for potential applications of camellia lecithin with characteristic phospholipid composition as alternative o/w emulsifiers in food industry.     

不同包装条件对米糠贮藏稳定性的影响

米糠资源营养丰富,具有很高的开发利用价值,但其贮藏稳定性差导致品质迅速下降。本实验以米糠为研究对象,分析自然贮藏条件下采用PE、PE/PA及编织袋包装的米糠在常压密封、真空密封条件下主要品质指标变化。结果发现：贮藏30d后,PE/PA/真空组水分含量下降0.99%,粗脂肪含量下降3.74%,脂肪酸值升高77.7mg KOH/100g,而对照组相应指标分别为PE/PA/真空组的3.6、2、5.33倍;PE/PA/真空组VE、γ-谷维素含量分别下降了0.4mg/100g、0.01%,对照组降幅分别是PE/PA/真空组的2.78倍和6倍;菌落总数PE/PA/真空组由初期的2.82×108CFU/g减少到0.3×107CFU/g,性状保持良好,具有米糠特有的香味,而对照组菌落总数增加到1.8×1010CFU/g,且出现明显的霉味,颜色变深,结块严重。结果表明不同包装对提高米糠贮藏稳定性效果依次为：PE/PA/真空＞PE/PA/常压＞PE/真空＞PE/常压＞编织袋＞对照,各样品结果呈显著差异(P＜0.05)。采用PE/PA真空包装贮藏能有效提高米糠贮藏期品质稳定性。     

Hydroxypropyl-Distarch Phosphate from Potato Starch Increases Fecal Output, but Does Not Reduce Zinc, Iron, Calcium, and Magnesium Absorption in Rats

The physiological effects of hydroxypropyl‐distarch phosphate (HDP) were examined in rats. Male rats were fed a fiber‐free purified diet containing gelatinized potato starch (PS, 50 g/kg diet) that was not modified chemically or gelatinized, chemically modified potato starch (CMS, 50 g/kg diet) for 21 d. PS was used as the control. Six kinds of gelatinized HDP from potato with 2 different degrees of hydroxypropylation and 3 different degrees of cross‐linking were used as CMS. The wet weight and moisture of the fecal output of the rats fed highly hydroxypropylated HDP was 70% and 30% greater, respectively, than that in the control rats. The weights of the cecal wall and content of the rats fed highly hydroxypropylated HDP were 15% and 30% higher, respectively, than those of the control rats. The apparent absorption of Mg was 15% higher in the rats fed highly hydroxypropylated HDP than in the control rats. On the other hand, the apparent absorptions of Ca, Zn, and Fe were not affected by the diet. Cross‐linking did not influence the above‐mentioned physiological effects of HDP. Fecal excretion of bile acids and the plasma cholesterol concentration were not affected by the diet. These results show that the physiological effects of HDP depend on the hydroxypropylation but not the cross‐linking.     

不同透明包装材料对东北酸菜褐变品质的影响

目的 研究不同透明包装材料对酸菜褐变的影响因素。方法 采用聚对苯二甲酸乙二醇酯/聚乙烯(polyethylene terephalate/polyethylene, PET/PE)、聚酰胺/流延聚丙烯薄膜(polyamides/retort cast polypropylene, PA/RCPP)、PA/CPE(chlorinatedpolyethylene)、PET/PA/RCPP 4种透明材料包装的酸菜为研究对象, 以聚酰胺/铝/聚乙烯(polyethylene terephalate/aluminum/polyethylene, PET/AL/PE)不透明包装的酸菜为对照, 测试分析贮藏期间酸菜的褐变度、色泽、氨基态氮含量、还原糖含量、VC含量变化情况。结果 各包装袋对酸菜褐变的抑制效果大小为PET/PA/RCPP>对照=PA/RCPP>PA/CPE=PET/PE, 其中PET/PA/RCPP包装袋明显降低了多酚的氧化缩合(P<0.05); PA/RCPP包装袋明显降低了VC的氧化分解(P<0.05); PET/PE和PA/CPE 2种包装袋对多酚和VC的效果不明显; 各组包装袋对氨基态氮和还原糖的影响不明显。结论 PET/PA/RCPP包装对抑制贮藏期间酸菜褐变有积极影响。