山嵛酸酰胺与芥酸酰胺的氧化稳定性研究

目的研究山嵛酸酰胺与芥酸酰胺的氧化稳定性。方法应用油脂氧化稳定性仪研究山嵛酸酰胺与芥酸酰胺的氧化稳定时间,并比较光照的影响;通过红外光谱仪与差示扫描量热仪(differential scanning calorimetry,DSC)研究加速氧化前后红外光谱图与热分析图谱的差异性;应用DSC研究芥酸酰胺在升温-降温-升温过程中的热特性以及山嵛酸酰胺升温过程中的热特性,并研究光照对样品热特性的影响。结果光照明显影响稳定时间,对芥酸酰胺的影响则更为敏感;加速氧化后出现羰基峰,山嵛酸酰胺在3300 cm~(-1)处峰形基本没有变化,而芥酸酰胺由双峰变为单峰,山嵛酸酰胺在700 cm~(-1)左右峰的强度无明显变化,而芥酸酰胺峰形明显增强;光照使芥酸酰胺熔融温度与结晶温度发生改变,山嵛酸酰胺除了熔融峰之外还有2个脂肪酸峰,光照影响熔融峰峰形。另外在加速氧化后进行热特性测试时,山嵛酸酰胺与芥酸酰胺熔融峰峰形正常,但峰值温度略有变化。结论山嵛酸酰胺与芥酸酰胺的油脂氧化稳定性,可以应用油脂氧化稳定性仪、差示扫描量热仪及红外光谱仪进行评价。     

工业硬脂酸、油酸、芥酸、山嵛酸及其衍生物原料、用途、市场状况

<正>前言 脂肪酸天然起始原料有动物脂肪和植物油脂两大类。动物脂肪中牛油和猪油内脂肪酸组分以棕榈酸(十六碳烷酸)和硬脂酸(十八碳烷酸)含量较高(参见表1和表2)。植物油脂中菜籽油含有较多量芥酸而棕榈油含棕榈酸占40％以上(参见表3)。菜籽油中芥酸含量高低与品种有关,如甘兰型油菜,泵高芥酸品种,芥酸含量高达57.2％(参见表4)。上述四种油脂脂肪酸组分中部含有一定量油酸和亚油酸以及少量或微量其他脂肪酸。     

芥酸的制取与应用

本文对芥酸的制取工艺和设备、芥酸及其衍生物的性质、用途及现状做了综述。对国内芥酸生产及其他油脂精细化工方面的开发研究有一定的参考价值。     

山嵛酸加工工艺的研究

<正> 一、前言山嵛酸,又名嵛树酸、扁油酸,分子式CH_3(CH_2)_(20)COOH,分子量为340.57。英文名称为Behenic Acid,为无色针状结晶或蜡状固体,它不溶于水,能溶于甲醇和乙醚,以甘油酯的形式存在于氢化菜油和氢化鱼油中。花生油、菜籽油中亦有少量存在,其文献指标如下: 熔点:79.95℃ d_4~(20)比重:0.822~(100)。沸点:306℃/60mmHg 折光指数n_0~(20):1.4270~((100)) 酸值:164.73 在国外,山嵛酸主要是从菜油和鱼油中经加工而制取的(有机合成的除外)。而在国内,目前尚无单位生产。从我国的现有状况来看,菜油资源丰富,芥酸含量高,一般可达     

芥酸的制取与应用

中国部分省区高芥酸菜籽中含芥酸４４－５２％。通过水解、氢化、蒸馏等工艺制取的芥酸中Ｃ２２：１占８８％以上，其中酸价１５８－１６８，碘价７１－８１，冻点２５－３５，色相２００以下。芥酸与氨在２００℃、１２５－１５０ＰＡ条件下反应所制取的芥酸酰胺，是优良的塑料增滑剂。芥酸的臭氧分解物壬二酸和巴西二酸可制取尼龙１３１３优质纤维，以及麝香的的代用品。此外，芥酸的其他各类衍生物在食品、医药、化妆品等方面也有着众多的用途。     

芥酸及其衍生物制取

介绍了芥酸的各种不同制取工艺，并概述了芥酸衍生物如芥酸甲酯、芥酸酰胺、山 酸等制取方法。     

山嵛酸低热量油脂的可用热量及安全性评价

以葵花籽油为标准进行21 d的大鼠生长试验,评价了含30%山嵛酸的低热量油脂的可用热量,得到其可用热量为25.8 kJ/g,与葵花籽油37.8 kJ/g相比降低了31.75%。添加5%、15%山嵛酸低热量油脂中未被吸收的山嵛酸分别为73.53%和81.24%。动物试验结果表明,山嵛酸低热量油脂对大鼠血清中的TG、TC、HDL-C、LDL-C以及AI值和AII值的影响与葵花籽油类似,不会升高发生动脉硬化的风险。     

负载型非晶态Ni-B/SiO2合金对芥酸加氢催化性能研究

研究了负载型非晶态Ni B/SiO2 合金催化剂对芥酸加氢制备山嵛酸的催化性能。结果表明 ,Ni B/SiO2 对芥酸加氢具有很高的活性 ,且稳定性较高 ,其催化性能优于非负载Ni B非晶态合金和RaneyNi催化剂。     

芥酸的生产及其衍生产品开发

芥酸具有用途广、附加值高、市场需求量大以及可再生等特点,是21世纪的重要精细化工原料。以芥酸为原料又可开发出一系列优良的衍生产品。目前芥酸主要从高芥酸菜籽油中制取。对芥酸的主要特性与用途、芥酸原料的生产、菜籽油中芥酸的制取以及芥酸衍生产品的开发等进行了介绍。     

超细Ni粉催化剂制备及对油酸加氢条件的研究

用化学还原法制备超细镍粉，用扫描电镜对样品的微观结构进行了表征。以超细镍粉作为加氢催化剂，在高压反应釜中考察反应压力、温度、时间、催化剂用量等条件对油酸氢化效果的影响。结果显示，随着反应压力、温度的增加，加氢效果增强；而催化剂用量、反应时间对加氢效果影响较小。     

Contamination of edible double-low oilseed rape crops via pollen transfer from high erucic cultivars

Contamination of double-low oilseed crops with pollen from high erucic varieties grown primarily on set-aside land may result in erucic acid concentrations above 2% resulting in its rejection as a double-low edible oilseed. An analysis of cross contamination between high and low erucic acid crops was carried out in field trials at Cockle Park, and Purley Farm, Essex in the 1992–1993 and 1993–1994 seasons. Contamination was generally low and at random across the test areas. This random fluctuations in erucic acid concentrations appeared to be due to insect activity rather than wind mediated pollen transfer. Roto-rod traps used at Cockle Park to measure pollen flow downwind from isolated blocks of oilseed rape showed that in both seasons a rapid exponential decline in pollen concentration occurred with distance from the source. Results presented in this study would suggest that contamination between edible and high erucic crops does not present a major problem under field scale cultivation. © 1998 SCI.     

不同炒籽工艺对低芥酸浓香菜籽油风味的影响北大核心CSCD

为了研究不同炒籽工艺对低芥酸浓香菜籽油风味的影响,以低芥酸油菜籽为原料,研究入炒水分、炒籽温度、炒籽时间对低芥酸浓香菜籽油风味物质含量及感官品质的影响。结果表明:从低芥酸浓香菜籽油中共鉴定出65种挥发性风味物质;随炒籽温度上升、炒籽时间延长,低芥酸浓香菜籽油中呈现烤香味的杂环类物质总含量逐渐增加;随炒籽温度上升和入炒水分的增加,呈现刺激味的硫苷降解产物(含硫类化合物、腈类化合物)总含量逐渐增加;在感官上,低芥酸浓香菜籽油主要体现为烤香味、焦糊味,还能感知到腌菜味和刺激味;随炒籽温度升高,低芥酸浓香菜籽油中烤香味感官属性得分先上升后降低,150℃时得分最高,而焦糊味、腌菜味等感官属性得分逐渐升高;随炒籽时间延长,烤香味感官属性得分逐渐降低,焦糊味感官属性得分逐渐升高;随入炒水分增加,烤香味、焦糊味感官属性得分在一定范围内稳定波动。炒籽过程中一定的炒籽温度及增加水分能够明显提升消费者喜好度。     

微波催化转移氢化红花油的研究

研究了红花油在密闭容器中微波辐射条件下，使用甲酸铵溶液作为载氢体、钯／碳作为催化剂的催化转移氢化(CTH)。与其他的催化转移氢化相比，该方法能比较好地将亚油酸完全转化成单不饱和脂肪酸，硬脂酸稍有增加。不用乳化剂或添加大量的水，使用微波CTH就具有选择性。     

Effects of abomasal infusions of fatty acids and 1-carbon donors on apparent fatty acid digestibility and incorporation into milk fat in cows

Our primary objective was to determine the effects of the abomasal infusion of 16-carbon (16C) and 22-carbon (22C) fatty acids (FA) on apparent FA digestibility, plasma FA concentrations, and their incorporation into milk fat in cows. Our secondary objective was to study the effects of 1-carbon donors choline and l-serine on these variables. Five rumen-cannulated Holstein cows (214 ± 4.9 d in milk; 3.2 ± 1.1 parity) were enrolled in a 5 × 5 Latin square experiment with experimental periods lasting 6 d. Abomasal infusates consisted of (1) palmitic acid (PA; 98% 16:0 of total fat), (2) PA + choline chloride (PA+CC; 50 g/d of choline chloride), (3) PA + l-serine (PA+S; 170 g/d of l-serine), (4) behenic acid (BA; 92% 22:0 of total fat), and (5) docosahexaenoic acid algal oil (DHA; 47.5% DHA of total fat). Emulsions were formulated to provide 301 g/d of total FA and were balanced to provide a minimum of 40 and 19 g/d of 16:0 and glycerol, respectively, to match the content found in the infused algal oil. Apparent digestibility of FA was highest in DHA, intermediate in PA, and lowest in BA. Digestibility of 16C FA was lowest in BA and highest in PA. The digestibility of 22C FA was highest in DHA relative to BA (99 vs. 58%), whereas 1-carbon donors had no effect on 22C FA digestibility. Plasma 16C FA concentrations were greatest with PA treatment, and 22C FA concentrations were ~3-fold greater in DHA-treated cows relative to all other treatments. Milk fat 16:0 content was highest in PA relative to BA and DHA (e.g., 37 vs. 27% in PA and DHA), whereas the milk yield of 16:0 was higher in PA relative to DHA (i.e., 454 vs. 235 g/d). Similarly, milk 22:0 content and yield were ~10-fold higher in BA relative to all other treatments, whereas DHA treatment resulted in higher content and yield of 22:6 in milk fat relative to all other treatments (41- and 38-fold higher, respectively). Consequently, the content of FA >16C (i.e., preformed) was higher in milk fat from cows infused with BA and DHA relative to PA. De novo FA content in milk did not differ between PA, PA+CC, and PA+S (~16% of milk fat) but was higher in BA and DHA treatments (19 and 21%, respectively). We conclude that FA carbon chain length and degree of saturation affected FA digestibility and availability for absorption as well as their incorporation into milk fat. The abomasal infusion of choline chloride and l-serine did not modify these variables relative to infusing palmitic acid alone.     

制备低反式酸氢化葵花油的研究

采用自制的负载型钯氧化铝催化剂,以反式脂肪酸含量为考察目标,通过单因素实验,研究了不同反应温度、反应压力、催化剂用量等条件对氢化油(氢化油碘值为75)中反式酸含量的影响。在单因素实验的基础上,采用响应面实验优化了氢化工艺参数,并进行了重复验证实验,得出低反式酸氢化葵花油反应的最佳工艺条件为:反应温度为52℃,反应压力为1.9MPa,催化剂用量为170mg/kg,此时的反式酸含量为10.59%。     

双戊烯催化加氢制备对孟烷工艺的研究

以工业双戊烯为原料,采用全循环法固定床加氢连续自动化控制生产工艺催化加氢制备对孟烷。试验比较颗粒Pd/C催化剂和镍系列改性催化剂B对双戊烯加氢反应的作用;通过单因素试验,分别考察反应温度、压力和时间等对双戊烯转化率和产物中对孟烷含量的影响;正交试验确定最佳工艺条件:当催化加氢反应的压力9.0MPa,温度220℃,时间4h时,双戊烯的转化率大于99.5%,产物中对孟烷含量达到97.1%。     

超临界条件下油脂氢化研究进展

近年来,反式脂肪酸带来健康问题日益引起人们关注,过多摄入反式脂肪酸将会引发心血管等多种疾病,而油脂氢化过程是产生反式脂肪酸主要来源之一;在超临界条件下进行油脂氢化可大大减少反式脂肪酸形成,已成为当前研究热点。该文主要介绍超临界流体特性及其在油脂氢化工艺中应用。