棕榈油与猪油在组成结构和功能特性上的比较

比较了3种棕榈油和6种猪油产品在理化指标、营养与功能特性指标以及脂肪酸组成及其在甘油三酯Sn-2位上的分布情况,以判断棕榈油对猪油的可替代性.结果表明,棕榈油和猪油的熔点、碘值、酸值、过氧化值等理化指标很接近;棕榈油不含胆固醇,具有比猪油较高的V_E含量和氧化稳定性;在可塑性方面,精炼棕榈油与猪板油相当,而且好于猪杂油和猪膘油,棕榈硬脂与猪骨油相当,棕榈液油与猪皮油相当;虽然棕榈油和猪油的脂肪酸组成具有相似性,猪油的不饱和脂肪酸含量略高于棕榈油的不饱和脂肪酸含量,但是棕榈油的Sn-2位上主要分布不饱和脂肪酸,而猪油的Sn-2位上主要分布饱和脂肪酸,使棕榈油比猪油更加容易消化吸收.     

热加工过程中棕榈油理化特性、脂肪酸与自由基的变化研究

以棕榈油（24℃）为原料,采用国标法测定棕榈油在不同温度（160、180、200℃）下常规理化指标（酸价、过氧化值、丙二醛值、p-茴香胺值和总氧化值）随时间的变化,在此基础之上,分别采用GC-MS法与电子自旋共振（ESR）法对180℃下棕榈油脂肪酸组成和自由基含量变化进行测定。结果表明,加热温度越高和加热时间越长棕榈油理化指标值越大,其中过氧化值呈现先上升后下降趋势。脂肪酸组成结果表明,棕榈油中饱和脂肪酸与不饱和脂肪酸比例约为1∶1,且随着加热时间延长,比例基本不变。ESR实验表明,加热时间越长,2-苯叔丁基硝酮（PBN）捕获的自由基量越多,棕榈油氧化程度越深。      

Effects of interesterified vegetable oils and sugar beet fibre on the quality of Turkish-type salami

Turkish‐type salami is an emulsion type product that is only shelf stable at chilling temperature. The use of three interesterified vegetable oils (IVOs) prepared from either palm, cottonseed or olive oil (IPO, ICO and IOO, respectively) together with 2% sugar beet fibre (SBF) (<425 μm) was studied in the production of Turkish‐type salami. These compounds were used to modify the fatty acid composition and increase the dietary fibre content of the traditional product. Beef fat (10%) was replaced by one of the IVOs at either 60 or 100%. The addition of SBF significantly increased (P < 0.05) the total dietary fibre content and water‐holding capacity of salamis. Incorporation of IVOs improved the nutritional content of the product because it altered the fatty acid composition. It was found that total or partial replacement of beef fat by IVOs, as well as the presence of 2% SBF, did not lead to significant changes in appearance, colour, texture, flavour or sensory score. The use of IVO and SBF as fat substitutes could be used to obtain a low fat product with high dietary fibre and a modified fatty acid composition.     

Technological characterization of the natural lactic acid bacteria of artisanal Turkish White Pickled cheese

The aim of this study was to characterize the lactic acid bacteria (LAB) isolated from White Pickled cheeses produced with traditional methods; and to improve the quality of cheesemaking with a selection of bacterial cultures from artisanal White cheeses. LAB were isolated and identified from 30 White Pickled cheese samples collected from various cities in Turkey. Also, the numbers of several microbial groups (total aerobic mesophilic bacteria, LAB, enterococci, coliforms, moulds and yeasts) of cheese samples were enumerated. Lactobacilli, lactococci and enterococci were the most abundant microbial groups. The numbers of Enterococcus and Lactobacillus isolates were higher than those of the other LAB. Enterococcus faecalis (24.43%), Enterococcus faecium (17.61%) and Lactobacillus fermentum (19.88%) isolates were the most frequently isolated species. Lactococcus strains showed the highest acidifying activity, followed by Enterococcus and Lactobacillus strains. Proteolytic activity of Enterococcus faecalis strains was higher than that of the other enterococci species, except Enterococcus avium strains. Within lactobacilli strains, the highest mean proteolytic activity was that of Lactobacillus bifermentans, Lactobacillus brevis and Lactobacillus casei strains.     

Application of hydrogenated palm kernel oil and palm stearin in whipping cream

Non-dairy creams made from hydrogenated palm kernel oil (HPKO) are generally more stable than dairy creams. However, in summer the emulsion tends to separate. This paper outlines some steps that were taken to modify the HPKO with the intention of increasing the stability without affecting whipping performance. This was achieved by blending HPKO with palm stearin (POs). Interesterification was employed to eliminate the increase in solid fat content at 37°C and 40°C. Results of the experiment showed that an interesterified HPKO: POs 66:34 blend proved to have satisfactory whipping performance when compared to creams made with HPKO alone.     

国产玉米毛油主要脂肪酸含量的分析

经过对全国各区域2 246个玉米毛油样品进行脂肪酸组分检测,分析研究了玉米毛油中主要脂肪酸组分的含量范围,其中棕榈酸11.5%~13.5%、硬脂酸1.5%~2.0%、油酸28.0%~34.0%、亚油酸50.0%~57.0%、亚麻酸0.50%~0.80%,检测结果符合国标中的质量指标要求。通过比较,国产玉米毛油的主要脂肪酸组分含量范围较为集中,有利于企业进行油种的识别和对产品质量进行控制和改善。     

Feeding a concentrate rich in rapeseed oil improves fatty acid composition and flavor in Norwegian goat milk

Impaired quality due to a high content of free fatty acids (FFA) and off-flavors has caused challenges in the development of Norwegian goat milk products. The present study aimed to examine the effect of lipid-supplemented concentrates on milk fat content, fatty acid composition, FFA, lipoprotein lipase activity, sensory properties, and size of milk fat globules of goat milk. Thirty goats assigned to 3 experimental groups were fed different concentrates from 60 d in milk (DIM) until late lactation (230 DIM). The diets were (1) control concentrate (no added fat); (2) control concentrate with 8% (added on air-dry basis) hydrogenated palm oil enriched with palmitic acid (POFA); and (3) control concentrate with 8% (added on air-dry basis) rapeseed oil (RSO). The POFA group produced milk with the highest fat content, and fat content was positively correlated with the mean size of milk fat globules. Goats in the RSO group had a higher content of long-chain and unsaturated fatty acids, whereas milk from goats in the POFA group had a higher content of palmitic and palmitoleic acids (C16:0 and C16:1 cis). The control group produced milk with a higher content of short-, medium-, odd-, and branched-chain fatty acids compared with the 2 other groups. The content of FFA in milk was low in early and late lactation and peaked in mid lactation (90 DIM). A high content of FFA was correlated with poor sensory properties (tart/rancid flavor). The RSO group produced milk with lower content of FFA and off-flavors in mid lactation and a higher proportion of unsaturated fatty acids. Therefore, replacement of palm oil with rapeseed oil as a lipid source in dairy goat feed would be favorable.     

五倍子油脂肪酸组成分析

以五倍子为原料,采用索氏法提取五倍子油,通过化学方法测定五倍子油常规理化性质,并用气相色谱仪分析五倍子油脂肪酸组成。试验结果表明,五倍子油索氏提取得率为0.72%;经气相色谱分析,五倍子油含有8种脂肪酸组分:月桂酸37.4%、肉豆蔻酸23.3%、棕榈酸13.9%、亚油酸13.9%、亚麻酸4.4%、油酸3.9%、硬脂酸2.2%,表明五倍子油是一种良好药用植物油。     

Directed interesterification of a brazilian palm oil and analysis of the original and interesterified oil and its fractions

A commercial sample of the Brazilian palm oil from the north eastern State of Bahia after neutralisation, washing and drying was interesterified in the presence of sodium-potassium alloy (NaK) at 30°C in a nitrogen atmosphere. The catalyst was destroyed by addition of water in a carbon dioxide atmosphere and the interesterified oil was crystallised from light petroleum, yielding an olein and stearin fraction. The fatty acid and triacylglycerol composition of the neutralised oil was determined by gas chromatography (g.c.) and high-performance liquid chromatography (h.p.l.c.) respectively and was shown to be similar to that of Malaysian and African palm oil. The compositions of the interesterified Brazilian oil and its liquid and solid fractions were also determined. The physicochemical characteristics of the olein obtained by interesterification with NaK, such as iodine value (96.8) and its softening point (below ?8°C) indicated its suitability for the use as salad oil.     

The fatty acid levels and physicochemical properties of herby brined cheese, a traditional Turkish cheese

In this study, some gross chemical compositions and fatty characteristics of herby cheeses were investigated. In the present study, the cheeses used as materials were collected from 10 different plants. The cheeses were made from sheep milk, cow's milk or a mixture of them, and stored in brine at 7–8°C and analysed for some proximate chemical compositions and fatty acid composition after 150 days of ripening. Capric acid, palmitic acid, oleic acid, short-chain fatty acids, medium-chain fatty acids, long-chain fatty acids, saturated fatty acids, monounsaturated fatty acids, polyunsaturated fatty acids and other fatty acids as g in 100 g fatty acids were determined.     

Effects of starter culture combinations using isolates from traditional cheese on the quality of Turkish white cheese

Four types of Turkish white cheese with good curd and acid formation properties were produced, one by using commercial starter culture and the other three by using different combinations of isolates from traditional cheese with no starters added. The effects of using these combinations on quality were determined. Starter culture combinations did not influence the chemical properties of cheese significantly. However, one cheese type produced from combinations of isolates of rural cheese was found to be comparable to the samples produced from commercial starter cultures in terms of sensory and microbial quality. This combination could have promise for white cheese production.     

功率超声和微波处理对花生油脂肪酸组成的影响

采用功率超声(频率为20 kHz,功率密度为345 W/cm2)处理和微波(375 W)处理花生油,并用气-质联用色谱(GC-MS)分别检测了未经物理场处理和物理场处理的花生油脂肪酸组成及其相对含量.结果表明,超声和微波处理对花生油的脂肪酸组成和相对含量有一定影响,但影响不显著.     

谷子油的理化性质及脂肪酸组成分析

对谷子的基本组成和谷子油的理化性质及脂肪酸组成进行了分析。结果表明,谷子中粗蛋白质、粗脂肪、总糖和淀粉含量分别为13.9%、5.6%、66.5%和63.7%。谷子油的酸值(KOH)为11.9 mg/g,碘值(I)为132.9 g/100 g,过氧化值为30.9 mmol/kg,皂化值(KOH)为194.4 mg/g,不皂化物含量为2.73%。谷子油主要由10种脂肪酸组成,其中饱和脂肪酸含量占16.81%,主要为棕榈酸(7.87%)、硬脂酸(6.17%)和花生酸(2.03%);不饱和脂肪酸含量达83.26%,其中以亚油酸含量(65.30%)最高,其次为油酸(14.20%)和亚麻酸(2.93%)。因此,谷子油是一种极具开发价值的营养保健油脂。     

鸵鸟油理化性质及脂肪酸组成分析

采用索氏提取法提取了在陕西养殖的鸵鸟油,室温分离得到液体油和固体脂.采用化学方法和气相色谱仪测定了两者常规理化指标和脂肪酸组成.结果表明,鸵鸟液体油和固体脂除碘值外其他理化指标稍有不同,其中脂肪酸组成及含量也有差异.液体油主要含有棕榈酸、油酸和亚油酸等,不饱和脂肪酸含量为63.96%,其中油酸含量最高,达到42.23%;固体脂主要含有棕榈酸、硬脂酸和油酸等,饱和脂肪酸含量为55.93%,其中棕榈酸含量最高,为45.23%.     

Extraction and physicochemical properties of low free fatty acid crude palm oil

Response surface methodology was applied to optimize the pre-treatment of oil palm (Elaeis guineensis) fruit spikelets before oil extraction. The treatment applied was drying at different times and temperatures. The dried spikelets were then subjected to mechanical processes and crude oil was extracted. A central composite design was employed to study the responses, namely percentage of free fatty acids (FFA) and oil yield, and the optimum conditions for minimum FFA and maximum oil yield were identified from their respective contour plots. It was concluded that the pre-treatment should be carried out for 12.8 h at 66.8 °C. Under the optimum conditions, the corresponding response values for FFA and oil yield were 1% and 33.6%, respectively. Some of the physicochemical properties of the extracted oil were then determined. The low free fatty acid crude palm oil exhibited good physicochemical properties and could be useful for industrial applications.     

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     

加工工艺对牡丹籽油脂肪酸成分、理化性质及抗氧化能力的影响

目的 研究加工工艺对牡丹籽油的脂肪酸组成、理化性质及抗氧化特性的影响。方法 采用直接冷榨法、炒制+冷榨法和超临界CO2萃取技术制取牡丹籽油, 以出油率、优质品质、脂肪酸组成和抗氧化能力为指标比较了不同工艺制备的牡丹籽油的品质。结果 直接冷榨的出油率(5.6%)远低于炒制+冷榨(8.3%)和超临界CO2萃取(8.2%), 直接冷榨制备的油脂品质和活性成分及抗氧化活性与超临界CO2萃取无显著性差异(P>0.05), 炒制+冷榨则会造成脂肪酸组成和抗氧化能力的较大差别(P<0.05)。结论 冷榨可以较好地保留牡丹籽油的活性成分和品质。     

The effect of palm oil or canola oil on feedlot performance,plasma and tissue fatty acid profile and meat quality in goats

Twenty-four entire male Kacang kid goats were fed diets containing 3% canola (n = 12) or palm oil (n = 12) supplements for 16 weeks. The goats had an initial live weight of 14.2 ± 1.46 kg and were fed a mixed ration ad libitum (10.4 MJ/ME and 14% crude protein). There was no difference in feedlot performance due to diet. Inclusion of canola oil reduced (P < 0.05) kidney fat weight and increased (P < 0.05) linolenic acid (18:3n − 3) concentration in the blood plasma, m. longissimus lumborum (LL), liver, and kidney. The palm oil diet increased (P < 0.05) myristic (14:0) and palmitic (16:0) acid content in the blood, but this did not alter these fatty acids in the LL muscle. Lipid oxidative substances in the liver and LL from palm oil fed kids were higher (P < 0.05) than those from canola supplemented kids. The incorporation of canola oil into the goats' diet increased muscle omega-3 fatty acid content, but lipid oxidation was lowered in the blood and muscle LL.