The content of tocopherols and oxidative quality of oils prepared from sunflower (Helianthus annuus L.) seeds roasted in a microwave oven

Sunflower seeds ((Helianthus annuus were roasted for 6, 12, 20 or 30 min at a frequency of 2450 MHz using a domestic microwave oven. After the kernels were separated from the sunflower seeds, the quality characteristics and the compositions of the oils were investigated in relation to their tocopherol distributions, and they were further evaluated as compared with an unroasted oil sample. Only minor increases (p < 0.05) in chemical and physical changes of the oils, such as the carbonyl value, the p‐anisidine value and the color development, occurred at a prolonged roasting period. Significant decrease (p < 0.05) was observed in the amounts of phospholipids in the oils after microwave roasting. Nevertheless, compared to the original level, more than 92 wt‐% tocopherols still remained after 30 min of roasting. With a few exceptions, these results indicate that the exposure of sunflower seeds to microwaves for 12 min caused no significant (p < 0.05) loss or change in the content of tocopherols and polyunsaturated fatty acids in the kernels.     

不同种类高膳食油脂对小鼠血脂、肝脂及尿酸的影响

为了探讨猪油、植物油及其调和油对血脂、肝脂及血尿酸的影响,评估其对特殊人群的健康潜在风险,本文研究以小鼠为模型,模拟居民用油习惯,将50只8周龄雄性C57BL/6J小鼠随机均分为葵花籽油组(SSO)、豆油组(SO)、猪油组(LO)、葵花籽油与猪油调和油组(SSO-L)、豆油与猪油调和油组(SO-L)5组,模拟我国部分人群(5%~10%)日均烹调油脂高摄入水平(95g/d),每组日粮中分别添加10.5%的不同油脂,饲喂8周后采集血液和肝脏组织,检测血清和肝脏指标。结果显示,相比于其他各组,LO组在体脂和血脂方面都有显著或极显著升高(p0.05,p0.01)。而SSO-L组和SO-L组在肝脂方面显著高于对应的SSO组和SO组(p0.05)。同时,SSO-L组和SO-L组的SUA和肝脏XOD水平都显著高于LO组(p0.05)。表明在95 g/d的膳食油脂摄入水平下,猪油会极大增加肥胖和患脂肪肝病的风险。葵花籽油与猪油调和油和豆油与猪油调和油也会通过升高尿酸水平来增大痛风和脂肪肝的患病风险。此外,长期以该水平摄入这两种调和油对肝脏功能也有明显损伤。在该摄入水平下,豆油为较优选择。     

响应面分析法优化乙醇提取向日葵壳红色素工艺研究

以向日葵壳为原料提取红色素。在单因素试验的基础上进行中心组合设计,利用响应面法对其提取工艺参数进行优化。结果表明：提取温度54℃、提取时间112min、液料比22:1(mL/g)时,向日葵壳色素提取量最高为663.03mg/100g,预测值为661.74mg/100g,与实测值相符。以向日葵壳提取色素可以提高向日葵的附加值。     

向日葵茎髓醇提物中不同溶剂萃取部位总酚、总黄酮含量与抗氧化活性的相关性

依次用石油醚、乙酸乙酯、正丁醇对向日葵茎髓乙醇提取物进行萃取,得到不同极性萃取部位, 测定石油醚萃取部位（PE）、乙酸乙酯萃取部位（EE）和正丁醇萃取部位（BE）的总酚和总黄酮含量及其 体外抗氧化活性,并分析其相关性。结果表明：EE中总酚和总黄酮含量均最高,分别为（1.60±0.10）mg/g 和（20.50±1.55）mg/g;且其1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）自由基清 除率（半抑制浓度（2.56±0.10）mg/mL）、2,2’-二氮-双（3-乙基苯并噻唑-6-磺酸）二铵盐（2,2’-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid),ABTS）自由基清除率（半抑制浓度（52.00±1.97）μmol/g）和铁离子还原能 力（半抑制浓度（120.57±0.74）μmol/g）也最好;总酚、总黄酮含量与抗氧化活性的相关性分析结果表明,各向 日葵茎髓萃取部位的DPPH自由基清除率、ABTS＋·清除能力及铁离子还原能力与其总酚和总黄酮含量均呈极显著 正相关（P＜0.01）。     

葵花籽粕酶法制备多肽的湿热预处理研究

以葵花籽粕为原料,以氮得率和热处理物总氮含量为评价指标,通过单因素试验分别研究pH、过筛目数、料液比、处理时间对葵花籽粕酶法制备多肽湿热预处理的影响。在此基础上,利用正交试验进行工艺优化得到湿热预处理最佳工艺条件为:pH 4.0,过筛目数60目,料液比1∶10,处理时间5 min。在最佳条件下,氮得率为98.14%,热处理物总氮含量为10.16%。     

The production of fuel from,and the thermal stability of,sunflower oil,corn oil,and canola oil

Frying of sunflower, corn, and canola oils was carried out for seven running days at 175°C in this study. Fatty acid composition, free fatty acid, viscosity, iodine value, peroxide value, density, pH, saponification value, refractive index, average molecular weight, color, and the higher heating value of these oils have been analyzed. While the contents of free fatty acid, viscosity, saponification value, peroxide value, and colors (red and yellow) increase with the frying times, the contents of average molecular weight, iodine value, pH, and the higher heating value decreased for all oils in this work. However, reduction in the higher heating value is relatively low. This work indicated that recycling as a fuel of these oils can make a major economic contribution.     

Catalytic Conversions in Aqueous Media. Part 2. A Novel and Highly Efficient Biphasic Hydrogenation of Renewable Methyl Esters of Linseed and Sunflower Oils to High Quality Biodiesel Employing Rh/TPPTS Complexes

An unusual high catalytic activity (TOF = 117,000 h⁻¹) and high catalyst productivity (TON = 9,700) have been achieved in the first example of partial hydrogenation of renewable polyunsaturated crude methyl esters of linseed and sunflower oils catalyzed by water soluble Rh/TPPTS complexes [TPPTS = P(C₆H₄-m-SO₃Na)₃] in aqueous/organic two-phase systems to afford monounsaturated fatty esters which is biodiesel first generation of improved oxidative stability, energy and environmental performance at a low pour point. This exceptionally high catalytic activity contrast with the general perception that industrially applied water soluble Rh/TPPTS catalysts normally exhibit very low rates in the conversions of higher molecular weight starting materials in aqueous/organic two-phase systems. For part 1 of this series see Ref. [14].     

New biofuel integrating glycerol into its composition through the use of covalent immobilized pig pancreatic lipase

By using 1,3-specific Pig Pancreatic lipase (EC 3.1.1.3 or PPL), covalently immobilized on AlPO(4)/Sepiolite support as biocatalyst, a new second-generation biodiesel was obtained in the transesterification reaction of sunflower oil with ethanol and other alcohols of low molecular weight. The resulting biofuel is composed of fatty acid ethyl esters and monoglycerides (FAEE/MG) blended in a molar relation 2/1. This novel product, which integrates glycerol as monoacylglycerols (MG) into the biofuel composition, has similar physicochemical properties compared to those of conventional biodiesel and also avoids the removal step of this by-product. The biocatalyst was found to be strongly fixed to the inorganic support (75%). Nevertheless, the efficiency of the immobilized enzyme was reduced to half (49.1%) compared to that of the free PPL. The immobilized enzyme showed a remarkable stability as well as a great reusability (more than 40 successive reuses) without a significant loss of its initial catalytic activity. Immobilized and free enzymes exhibited different reaction mechanisms, according to the different results in the Arrhenius parameters (Ln A and Ea). However, the use of supported PPL was found to be very suitable for the repetitive production of biofuel due to its facile recyclability from the reaction mixture.     

Evaluation of high oleic-high stearic sunflower hard stearins for cocoa butter equivalent formulation

Cocoa butter equivalents (CBEs) are produced from vegetable fats by blending palm mid fraction (PMF) and tropical butters coming from shea, mango kernel or kokum fat. In this regard, high oleic-high stearic (HOHS) sunflower hard stearins from solvent fractionation can be used in CBE production since their compositions and physical properties are similar to those found in the above-mentioned tropical butters. In this work, three sunflower hard stearins (SHS) ranging from 65% to 95% of disaturated triacylglycerols and a shea stearin (used as reference) were blended with PMF to evaluate their potential use in CBEs formulation. Isosolid phase diagrams of mixtures of PMF/SHS showed eutectic formation for SHS 65 and SHS 80, but monotectic behaviour with softening effect for SHS 95. Three CBEs from SHS and shea stearin were formulated according to phase behaviour diagrams and solid fat content data at 25 °C. Isosolid phase diagrams of mixtures of these CBEs with cocoa butter showed no eutectic behaviour. Therefore, CBEs elaborated from SHS exhibited full compatibility with cocoa butter.