上海市场五种食用油反式脂肪酸含量测定

对上海市场上五种食用油的反式脂肪酸含量进行了测定.五种食用油总反式脂肪酸的平均含量为:橄榄油(0.03%),茶籽油(1.01%),葵花籽油(1.43%),大豆油(1.52%),玉米油(2.44%).除橄榄油以外,其他四种食用油产品总反式脂肪酸的含量均在1%以上.大豆油、玉米油和葵花籽油都是上海居民消费的主要食用油产品,其反式脂肪酸含量值得重视.     

酶催化酯交换法制备零反式脂肪酸人造奶油基料油的理化性质研究

以松籽油和棕榈油硬脂为原料,通过酶催化酯交换法生产零反式脂肪酸人造奶油基料油。酯交换反应得到油脂的主要脂肪酸组成为:棕榈酸(37.88%),油酸(28.30%),亚油酸(20.19%),同时含有少量功能性脂肪酸——松籽油酸(4.77%),且没有检测到反式脂肪酸;结构脂质的熔点为37.5℃,其固态脂肪含量在20、25、30℃和40℃时分别是40.28%、32.62%、22.06%、3.40%,并且其主要晶型是β’型。因此,酯交换反应得到的零反式脂肪酸油脂适合作为人造奶油的基料油。     

气相色谱-质谱法分析鸡枞菌中脂肪酸组成

分析鸡枞菌中脂肪酸的含量和组成。采用索氏提取法提取鸡枞菌中的脂肪酸,经甲酯化后采用气相色谱-质谱联用法(gas chromatography mass spectrometry,GC-MS)对脂肪酸进行测定。结果表明:鸡枞菌中分离并鉴定出5种脂肪酸,分别为月桂酸(35.2%),肉豆蔻酸(23.2%)、十五烷酸(11.0%)、棕榈酸(12.3%);亚油酸(18.3%),其中饱和脂肪酸占脂肪酸总量的81.7%。为鸡枞菌的营养价值评价和食品开发提供试验依据。     

不同营养强化对褶皱臂尾轮虫脂类和脂肪酸组成的影响

试验采用30%鱼油+70%酵母(A组),20%鱼油+80%酵母(B组),10%鱼油+10%磷脂+80%酵母(C组),100%酵母(D组)、等鞭金藻(E组)五种方式培养褶皱臂尾轮虫.结果表明:轮虫的总脂含量和脂肪酸组成与培养方式密切相关,与其它方式强化的轮虫相比,鱼油强化组都含有较高的总脂含量.其中B组轮虫的二十碳五烯酸(EPA)含量最高,占其总脂肪酸的12.72%;E组轮虫的二十二碳六烯酸(DHA)含量最高,占其总脂肪酸的9.80%;D组轮虫的二十二碳六烯酸(DHA)含量最低,占其总脂肪酸的2.55%.     

青海牦牛乳脂肪Sn-2位脂肪酸组成分析

以采自青海地区不同海拔高度的的牦牛乳脂肪为研究对象,利用气相色谱仪及薄层层析法测定牦牛乳脂肪的Sn-2位脂肪酸的组成,并研究不同海拔高度的牦牛乳脂肪的Sn-2位脂肪酸组成是否存在显著性差异,并分析其原因。结果表明青海牦牛乳脂肪的甘油三酯的总脂肪酸共有12种,含量较高的为棕榈酸(31.35%～36.48%),油酸(24.91%～30.99%)和硬脂酸(9.82%～13.87%)。青海牦牛乳脂肪的Sn-2位脂肪酸组成为:己酸(0.66%～1.02%),癸酸(2.46%～3.98%),月桂酸(2.43%～4.88%),十四烷酸(14.66%～20.68%),十五烷酸(1.19%～1.76%),棕榈酸(39.91%～46.23%),棕榈油酸(2.81%～5.35%),硬脂酸(4.75%～8.31%),油酸(17.42%～20.81%),亚油酸(0.00%～～1.72%),亚麻酸(0.00%～1.71%)。显著性分析显示:随着海拔的升高,结合在牦牛乳甘油三酯Sn-2位上的饱和脂肪酸(SFA)占比先逐渐升高,后显著降低(P0.05)。不饱和脂肪酸(UFA)的占比先逐渐降低,趋于平缓后显著升高(P0.05)。     

GC-MS法测定宣威火腿中脂肪酸组成

以宣威火腿为对象,通过提取成熟宣威火腿的肌间脂肪和皮下脂肪,采用气相色谱-质谱联用法(GC-MS)对宣威火腿肌间脂肪与皮下脂肪中脂肪酸的组分进行探讨。结果表明:宣威火腿肌间脂肪中含11种饱和脂肪酸,占总脂肪酸的34.75%,15种不饱和脂肪酸,占总脂肪酸含量的64.78%,主要的脂肪酸为油酸(C18∶1)、棕榈酸(C16∶0)、硬脂酸(C18∶0)、亚油酸(C18∶2),含量分别为33.44%、23.37%、8.44%、20.55%;皮下脂肪中含11种饱和脂肪酸,占总脂肪酸的36.23%,15种不饱和脂肪酸,占总脂肪酸含量的63.47%,主要的脂肪酸为油酸(C18∶1)、棕榈酸(C16∶0)、硬脂酸(Cl8∶0)、亚油酸(C18∶2),含量分别为31.47%、21.90%、11.13%、22.39%。     

遏蓝菜种子油理化性质及脂肪酸组成的GC-MS分析

为了探究遏蓝菜种子油理化性质以及脂肪酸成分,用索氏提取法提取遏蓝菜种子油,对遏蓝菜种子油的理化性质进行测定,用气相色谱质谱联用仪(GC-MS)法分析其脂肪酸组成及相对质量分数。结果表明:种子含油率为43.93%;常温下估测密度为0.88 g/mL;酸值为2.27 mgKOH/g;碘值为124.27 gI2/100 g;皂化值为198.33 mgKOH/g;种子油中主要含有芥酸(31.06%),亚油酸(24.83%),油酸(14.55%),亚麻酸(11.33%),11-二十碳烯酸(4.88%),棕榈酸(5.18%),15-十四碳烯酸(3.23%),硬脂酸(0.57%)9种脂肪酸。为遏蓝菜作为生物质能源的开发利用提供一定的科学参考。     

中空纤维支撑液膜结合气相色谱测定肉中挥发性脂肪酸

利用中空纤维支撑液膜萃取结合气相色谱测定肉中的挥发性脂肪酸,并建立和验证此方法。中空纤维支撑液膜能够对已酸化的肉浆上清液进行选择性富集。中空纤维管中的萃取物,经盐酸酸化后可直接进行气相色谱分析。此方法线性相关好(r≥0.9261),检测限较低(0.03～0.16μmol/L),回收率可接受(71.0%～123.1%),日内精密度(7.82%～10.28%)和日间精密度(10.01%～15.96%)良好。畜肉中的挥发性脂肪酸含量(725.30～845.23mg/kg)明显高于禽肉中(192.82～282.39mg/kg)。猪肉中总挥发性脂肪酸含量与其pH值呈负相关(r=0.7592),与挥发性盐基氮负相关良好(r=0.7890),此结果表明总的挥发性脂肪酸有可能作为肉新鲜度的检测指标。     

驴肉脂肪和脂肪酸组成的分析与评价

本文分析驴肉的脂肪含量,并采用气相色谱法对驴肉的脂肪酸成分及含量进行测定.结果表明,驴肉中粗脂肪含量为5.02%,不饱和脂肪酸含量占脂肪酸含量的,55.8%,饱和脂肪酸占44.2%.脂肪酸中棕榈酸C16:0(55.2%)含量最高,其它由高到低依次为油酸(33.0%)、亚油酸(10.1%),棕榈油酸(8.1%)、硬脂酸(6.7%)、肉豆蔻酸(4.1%)、花生四烯酸(2.0%).驴肉中的脂肪酸能较好地满足人体的营养需求.     

省沽油种子油中脂肪酸的GC-MS分析

用二氯甲烷提取省沽油种子油,并进行皂化、甲酯化,用GC-MS对省沽油种子油中的脂肪酸组成进行了分析,并对野生与种植两种省沽油种子油中的脂肪酸种类与含量进行了对比.结果表明,省沽油种子油中含多种脂肪酸(共检出20种),主要是亚油酸、亚麻酸、油酸和棕榈酸,其中亚油酸含量分别为48.50%(野生)和57.60%(种植),亚麻酸含量为8.86%(野生)和10.12%(种植), 不饱和脂肪酸总量为70.22%(野生)和80.31%(种植).野生与种植两种省沽油种子油中的脂肪酸种类基本相同,但种植的种子油中不饱和脂肪酸含量比野生的高10.09%.     

基于脂肪酸组成结合主成分分析识别不同比例大豆油和菜籽油调配的调和油

结合脂肪酸组成和化学计量学方法,对大豆油、菜籽油及其不同比例的二元调和油的识别进行基础研究,并分析不同比例调和油中脂肪酸含量的变化。结果表明在大豆油和菜籽油中,共检出脂肪酸组分17种,主要以油酸、亚油酸、棕榈酸和亚麻酸为主。在以不同比例低芥酸菜籽油和大豆油调配的调和油中,脂肪酸含量随调和比例的改变而呈现一定趋势的增加或减小。结合脂肪酸组成,对所有的139个样品进行了主成分分析(PCA),结果表明大豆油和菜籽油可以互相实现区分,不同比例的调和油样品分布在调配的溯源样品之间,基本按照比例关系分布成一条直线。研究通过对菜籽油、大豆油及其不同比例调配的调和油的脂肪酸组成进行了定量分析,分析了它们之间脂肪酸组成的变化,并结合化学计量学手段进行一些识别分析,为规范调和油的生产和保障公平有序的调和油市场提供参考。     

Extraction and physicochemical properties of soya bean protein and oil by a new reverse micelle system compared with other extraction methods

Reverse micelle extraction is a novel technology for the separation of plant components such as proteins and oil. In this study, sodium bis(2‐ethylhexyl) sulphosuccinate (AOT) reverse micelle system and AOT/Tween 85 reverse micelle system were used to extract soya bean protein and oil from soya bean flour. The physicochemical properties of the protein and oil extracted were investigated and compared with traditional extraction methods. The results showed that the efficiency of forward extraction of soya bean protein using an AOT/Tween 85 reverse micelle system was superior to that using an AOT reverse micelle system at the optimal extraction conditions. In addition, soya bean proteins extracted using reverse micelle extraction had no unordered structure under Fourier transform infrared spectroscopy. The acid and peroxide values of oil products from two reverse micelle extractions were lower than that from immersion. The results indicated that AOT/Tween 85 reverse micelle system is effective in extracting soya bean protein and oil.     

Quality assessment of refined oil blends during repeated deep frying monitored by SPME–GC–EIMS,GC and chemometrics

The aim of this study was to investigate the effect of the refined palm oil addition (20%) on the fatty acid and sterol compositions of refined olive oil or refined soya bean oil and also to investigate the formation of total polar compounds and volatile compounds in these oil blends during fifty successive deep‐frying sessions of potato fries at 180 °C. The blend of refined olive oil and refined palm oil exhibited a higher chemical stability during the frying process than that of refined soya bean oil and refined palm oil. Indeed, the total polar compounds and volatile compounds formed, especially 2,4‐decadienal, were found to be relatively increased in the refined soya bean oil/refined palm oil blend reaching 36.50% and 46.70%, respectively, after fifty deep‐frying sessions. Moreover, the degradation of linoleic acid and β‐sitosterol was significantly (P < 0.05) observed for the refined soya bean oil/refined palm oil blend. The results have proven that the proper blending of monounsaturated refined olive oil with refined palm oil increases its stability and hence improves the quality of such olive oil during frying process.     

Quantitative changes in some unsaponifiable components of soya bean oil due to refining

The effects were studied of the processes of degumming, neutralisation, bleaching and deodorisation on the content and composition of the various fractions of unsaponifiables in soya bean oil. The effect of each of the various technological steps on the decrement of the investigated unsaponifiables in the processed oils was different. When compared with the crude oil, the refined soya bean oil contained less tocopherols (by 31 to 47%), sterols (by 25 to 32%) and squalene (by 15 to 37%). No significant differences were observed in the compositions of the sterol and tocopherol fractions of the crude and refined soya bean oils.     

Influence of malting on selected components of soya bean,black bean,chickpea and barley

The influence of malting for 24 and 48 h on selected components was studied in soya bean, black bean, chick pea and barley. Proximate composition, calcium, iron zinc, α-galactosides including ciceritol, sucrose, phytic acid, myo-inositols phosphate and lectins were determined. The malting conditions were adequate to maintain the overall proximate composition and minerals. Galactosides decreased rapidly in all samples. Two days malting promoted a decrease of 91 and 84% in black bean and barley, respectively, while 44% was observed in the soya bean and only 34% in chickpea with a loss of 43% of ciceritol. The highest total levels of inositol phosphates were found in soya bean and black bean (478 and 450 mg%, respectively). IP6 and IP5 were not intensively affected by malting with the higher decrease of 25% observed in black bean. Lectin was detected in significant amounts only in soya bean and black bean and malting promoted 76% loss after 48 h in the black bean samples. The results indicated that short time malting may be useful to improve nutritional characteristics of the samples and that within the legume seeds studied black bean showed better results. ©     

Feeding differently processed soya bean. Part 1. Effect on performance, protein utilization, relative organ weights, carcass traits and economics of producing broiler-chickens.

The comparative utilization of differently processed (roasted, cooked and oil cake) soya bean base diets and groundnut cake diet were evaluated in a feeding trial using 100 day-old Anak broiler-chicks. The response criteria included performance, protein utilization, relative organ weights, carcass traits and economy of production. At the end of the feeding trial, the average weight gains of chicks fed processed soya bean diets were significantly (P less than 0.05) higher than those fed groundnut cake and raw soya bean diets. Both feed consumption and efficiency were significantly (P less than 0.05) enhanced by processing. For example, feed consumption was highest in the chicks fed soya bean oil cake and least in those fed raw bean. Feed efficiency was best in chicks fed roasted soya bean. The relative weights [g/100 g body wt.] of the liver, kidneys, lungs, heart, gizzard and bursa were not significantly affected by the differently processed soya bean while the raw bean (unprocessed) significantly (P less than 0.01) increased pancreas weight. The dressed weight [%], eviscerated weight [%] and the relative weight of the thigh, drumsticks, chest, back and head were not significantly influenced by the dietary treatments. However, the relative weights of the shank and belly fat were significantly (P less than 0.05) affected. Cost-benefit analysis showed that the processed soya bean gave higher profit than groundnut cake diet. Among the soya bean diets, profit was in the order: roasted greater than cooked greater than oil cake greater than raw bean.     

Feeding differently processed soya bean Part 1. Effect on performance,protein utilization,relative organ weights,carcass traits and economics of producing broiler-chickens

The comparative utilization of differently processed (roasted, cooked and oil cake) soya bean base diets and groundnut cake diet were evaluated in a feeding trial using 100 day-old Anak broiler-chicks. The response criteria included performance, protein utilization, relative organ weights, carcass traits and economy of production. At the end of the feeding trial, the average weight gains of chicks fed processed soya bean diets were significantly (P < 0.05) higher than those fed groundnut cake and raw soya bean diets. Both feed consumption and efficiency were significantly (P < 0.05) enhanced by processing. For example, feed consumption was highest in the chicks fed soya bean oil cake and least in those fed raw bean. Feed efficiency was best in chicks fed roasted soya bean. The relative weights [g/100g body wt.] of the liver, kidneys, lungs, heart, gizzard and bursa were not significantly affected by the differently processed soya bean while the raw bean (unprocessed) significantly (P < 0.01) increased pancreas weight. The dressed weight [%], eviscerated weight [%] and the relative weight of the thigh, drumsticks, chest, back and head were not significantly influenced by the dietary treatments. However, the relative weights of the shank and belly fat were significantly (P < 0.05) affected. Cost-benefit analysis showed that the processed soya bean gave higher profit than groundnut cake diet. Among the soya bean diets, profit was in the order: roasted > cooked > oil cake > raw bean.     

The use of chromic oxide as a food marker —a warning

Four mixtures of ground barley and soya bean meal were prepared; the first had no further additive, the second had 10% soya bean oil, the third 0.05% chromic oxide and the fourth both 10% soya bean oil and 0.05% chromic oxide. Each of these mixtures was then dried in three ways: at 30°C in vacuo and at 60 and 100°C in a forceddraught oven. The total fatty acid content and the fatty acid composition of each sample was determined either by direct esterification of the fatty acids with methanolsulphuric acid or by extraction into chloroform-methanol followed by esterification with sodium methoxide. When the mixture containing both oil and chromic oxide was heated at 100°C, about 25% of the polyunsaturated fatty acids were lost when they were directly esterified and about 50% when the fat was first extracted from the mixture. It is concluded that this loss is probably due to oxidation of the polyunsaturated fatty acids by the chromic oxide and that the additional loss observed when the extraction method was used is due to partial insolubilisation of the triglyceride by these oxidised fatty acids.     

Feeding differently processed soya bean. Part 2. An assessment of haematological responses in the chicken.

The use of differently processed soya bean as a major source of dietary protein was evaluated in a haematological study using broiler chickens in which groundnut cake (GNC), raw soya bean (RSB), roasted soya bean (RtSB), cooked soya bean (CSB) and soya bean oil cake (SBC) were fed on equi-protein basis. The results showed that: 1. Red blood cell (RBC) count and haemoglobin content of blood significantly (P less than 0.05) increased in chicks fed RSB relative to the other soya bean diets. Feeding differently processed soya bean significantly (P less than 0.05) influenced mean cell haemoglobin (MCH) and mean corpuscular volume (MCV) while the mean corpuscular haemoglobin concentration (MCHC) was not significantly influenced. 2. Both the total white blood cell (WBC) count and the monocytes were significantly (P less than 0.05) influenced by the dietary treatments. Chicks fed processed soya bean generally had higher number of monocytes. 3. Physical properties determined were specific gravity and erythrocyte sedimentation rate. The latter was significantly (P less than 0.05) lower in all the processed soya bean-fed chicks. 4. Minerals determined in blood were Na, K, Ca, Mg, Fe, Cu and P. Of all these, chicks fed RSB had significantly (P less than 0.01) lower levels of blood Mg and marked decrease in Ca.     

Optimisation of soya bean oil bleaching by ultrasonic processing and investigate the physico‐chemical properties of bleached soya bean oil

In this study, an ultrasonic bleaching method for soya bean oil under different conditions was optimised by monitoring the reduction of oil‐containing colourants. Ultrasonic power, clay content, temperature and time had a significant interaction effect on (P < 0.05) the reduction of oil pigments and colourants. Under optimised conditions, red and yellow colour indices in the ultrasound‐bleached soya bean oil reduced to 74.44% and 75.55%, and 54.18% and 58.85%, respectively, at amplitudes of 85% and 65%. Carotenoid and chlorophyll concentrations also reduced to 81.19% and 83.62%, and 94.66% and 95.26%, respectively, at 85% and 65% ultrasonic power. The overall contents of sterols and tocopherols decreased using ultrasonic bleaching process compared with the neutralised soya bean oil. Although the peroxide value (PV) of the soya bean oil after ultrasonic and control bleaching reduced, this index was higher in the ultrasonic bleached oil than the control one. The results showed that the ultrasonic bleaching process could be an alternative to the industrial bleaching method as it reduced clay usage, temperature and time of bleaching about 35%, 35% and 10%, respectively.