现代制皂法 第三讲皂基制备(二):脂肪酸中和

脂肪酸中和是皂基制备的又一重要方法。脂肪酸工业的发展与脂肪酸生产技术的进步,为制皂工业的发展创造了更好的条件。在许多国家中。

肥皂及棕榈油和月桂油

前言目前脂肪酸甲酯主要用作制脂肪醇的中间体,从其理化性质看,脂肪酸甲酯与脂肪酸相比具有下述优点:由于其熔点较低,处理方便,贮存期间性能较稳定,对所使用的设备没有腐蚀性;并且由于沸点较低,容易蒸馏。脂肪酸甲酯有两条制备路线:(1)由油脂裂解获取的脂肪酸直接酯化,(2)用甲醇同油脂直接酯交换(甲醇分解法)。根据第2条路线,具有上述优点的甲酯能以相对较低的成本进行生产。所以这些酯作为各种脂肪酸衍生物的中间体而获得重新评价。在各种油脂原料中。

Lipid and Fatty Acid Compositions of Cod (Gadus morhua),Haddock (Melanogrammus aeglefinus) and Halibut (Hippoglossus hippoglossus)

This study was conducted to compare lipid and fatty acid composition of cod,haddock and halibut.Three groups of cod（276 g±61 g）,haddock（538 g±83 g）and halibut（3704 g±221 g）were maintained with commercial feeds mainly based on fish meal and marine fish oil for 12 weeks prior to sampling.The fatty acid compositions of muscle and liver were determined by GC/FID after derivatization of extracted lipids into fatty acid methyl esters（FAME）.Lipids were also fractionated into neutral and polar lipids using Waters silica Sep-Pak（R）.The phospholipid fraction was further separated by high-performance thin-layer chromatography（HPTLC）and the FAME profile was obtained.Results of the present study showed that cod and haddock were lean fish and their total muscle lipid contents were 0.8% and 0.7%,respectively,with phospholipid constituting 83.6% and 87.5% of the total muscle lipid,respectively.Halibut was a medium-fat fish and its muscle lipid content was 8%,with 84% of the total muscle lipid being neutral lipid.Total liver lipid contents of cod,haddock and halibut were 36.9%,67.2% and 30.7%,respectively,of which the neutral lipids accounted for the major fraction（88.1%-97.1%）.Polyunsaturated fatty acids were the most abundant in cod and haddock muscle neutral lipid.Monounsaturated fatty acid level was the highest in halibut muscle neutral lipid.Fatty acid compositions of phospholipid were relatively constant.In summary,the liver of cod and haddock as lean fish was the main lipid reserve organ,and structural phospholipid is the major lipid form in flesh.However,as a medium-fat fish,halibut stored lipid in both their liver and muscle.

Lipids and fatty acids in Calanus sinicus during over-summering in the southern Yellow Sea

Over-summering is a crucial period for Calanus sinicus in the southern Yellow Sea,where it is a key member of the zooplankton community.Lipids play an important role in copepod diapause,which is part of their over-summering strategy.We investigated how different fatty acids and lipid classes,including wax esters,changed during over-summering of C.sinicus during three cruises in June and August 2011 and November 2010,corresponding to the pre-,during and post-diapause periods,respectively.Large amounts of lipids were accumulated,mainly wax esters as previously found in C.finmarchicus during its diapause,and most of the storage lipids were used during over-summering.Wax ester polyunsaturated fatty acids(PUFAs) showed the most variation of the fatty acids(FAs),while the percentage composition of FAs in polar lipids was relatively stable.Selective use of wax ester PUFAs has already been shown to play important roles in the winter diapause of Calanus species in other regions,and our FA results show that this is the case for the Yellow Sea Cold Bottom Water(YSCBW) population that diapauses in summer.

Temperature effects on lipid properties of microalgae Tetraselmis subcordiformis and Nannochloropsis oculata as biofuel resources

Microalgae Tetraselmis subcordiformis and Nannochloropsis oculata were cultured at 15,20,25,30,and 35℃ and their properties as potential biofuel resources were examined.The results indicate that T.subcordiformis and N.oculata grew best at 20℃ and 25℃ and yielded the highest total lipids at 20℃and 30℃,respectively.With increased temperature,neutral lipid and polyunsaturated fatty acids(FAs)decreased while saturated FAs increased,accompanied by increased monounsaturated FAs(MUFAs) in T.subcordiformis and decreased MUFAs in N.oculata;meanwhile,the predicted cetane number of FA methyl esters increased from 45.3 to 47.6 in T.subcordiformis and from 52.3 to 60.3 in N.oculata.Therefore,optimizing culture temperatures is important for improving microalgal biodiesel production.

Practical Application of Diets Rich in Ground Linseed to Enhance Omega-3 Milk Production in Holstein Dairy Farms Located in Northeast Iran

In an attempt to enhance organic omega-3 milk production, a practical study was performing in 7 Holstein dairy farms in Northeast Iran. The experiment was conducted at the ＂ShafashirToos industrial dairy farmers production and distribution cooperative＂ located in Northeast Iran, between June 2010 and December 2010. In Golshid-Mashhad Co., cows were fed with no linseed containing diets （NO-Lin）, while in the other farms （Hanaei Co., Ghasemi Co., Taheri Co., Teliseh Co., Arasp Co. and Navingholshid-Khorasan Co.）, cows were fed diets containing 9% ground linseed （Lin）. Cows were used in a randomized complete block experimental design. Diets were provided as TMR. Concentration of fat, protein and lactose in milk was measured. Milk fat extraction and fatty acid separation were determined. There were no differences in the most of the milk fatty acid profiles of cows in farms that received ground linseed but feeding Lin diets compared with NO-Lin, significantly decreased （P 〈 0.05） C8：0-C16：0 concentration and it increased those of C 18：1 n9trans, C 18：1 n9cis, C 18：2 trans and C 18：3 n3. As a result, farms with Lin diets had better milk fatty acid profiles with doubled in a-Linolenic acid concentration and increased in mono and polyunsaturated fatty acids and decrease in medium chain and saturated fatty acids compared with those of the NO-Lin diet. These results clearly demonstrate the possibility for sustainable production of organic omega-3 milk with levels ofC18：3 FA up to 2.4 times higher than typical levels in dairy fat. The manufacture of omega-3 enriched milk and milk products could supply dietary fatty acids at levels that may henefit health, without the need for unrealistic changes to eating habits.