烷醇酰胺衍生物的制备及应用

将脂肪酸甲酯与不同摩尔分数的醇胺制备成烷醇酰胺衍生物,测定贮存稳定性及其水乳液的稳定性,同时考察其加脂性能。结果表明,以合适摩尔比的醇胺混合物制成的烷醇酰胺衍生物流动性能良好,易乳化,储存稳定;乳液对10%栲胶溶液、10%硫酸铬钾溶液、0.1mol/L盐酸溶液、0.1mol/L氢氧化铵溶液稳定;加脂后的坯革撕裂强度为9.622N/mm、抗张强度为3.645N/mm2、断裂伸长率为89.801%;加脂后的坯革柔软、丰满,有弹性,耐热老化性能优良。     

磺化脂肪酸烷醇酰胺羧酸酯的研制及应用

将脂肪酸甲酯磺酸钠进行酰胺化及酯化反应,得到了磺化脂肪酸烷醇酰胺羧酸酯。将其应用于绵羊鞋面革的加脂工段,并对加脂成革的部分物性进行了测试。同时考察了其染色、加脂后所收集废水的氨氮值、化学需氧量(COD)和浊度。结果表明:磺化脂肪酸烷醇酰胺羧酸酯用作加脂剂后,单独使用效果不佳。若将其作为加脂剂与其他加脂剂复配使用,其成革革身不油腻、手感自然舒适柔软、弹性好,且加脂后,加脂成革的物性指标可达行业标准,废水减排令人满意。     

烷醇酰胺类皮革加脂剂

烷醇酰胺(alkanoIamide)是长链脂防酸和二乙醇胺的缩合产物用烷醇酰胺可制得一类性能很好的皮革加脂材料。加脂时受浴液酸碱度和无机盐的影响较小,加脂后的革手感柔软,丝光感较好,     

基于FTE改性的两性加脂剂的制备及应用

以长链脂肪酸、三乙醇胺、顺丁烯二酸酐和无水亚硫酸钠为主要原料,制备了基于脂肪酸三乙醇胺酯类改性的两性加脂剂(FTAF)系列,通过傅里叶变换红外光谱对脂肪酸三乙醇胺酯类(FTE)与FTAF的结构进行了表征,对其乳化能力和等电点进行了测定,并将其应用于皮革加脂中,探索了FTAF结构变化对坯革染色性能、柔软度及物理机械性能的影响。结果表明:FTAF系列的等电点在2.5~4.3,且均具有较好的匀染性;在FTAF系列产品中,以棕榈酸和硬脂酸制备的FTAF具有较好的乳化能力。其中基于棕榈酸三乙醇胺单酯制备的FTAF也表现出优异的促染性,其染色坯革的K/S值较硫酸化蓖麻油和阴离子性半合成油分别提高1.312和5.026;经基于棕榈酸三乙醇胺单酯制备的FTAF处理的坯革的柔软度、耐干湿擦色牢度、抗张强度以及撕裂强度表现优异。     

烷醇酰胺琥珀酸单酯磺酸二钠盐的助鞣性能研究

在传统铬鞣工序中应用加脂剂不仅有助鞣作用，而且能赋予蓝坯革一定的加脂效果。我们在实验中合成了两种烷醇酰胺琥珀酸单酯磺酸二钠盐──Ｎ—２—羟乙基烷基酰胺琥珀酸单酯磺酸二钠［简称ＨＥＡＡＳＳ］和Ｎ，Ｎ—二（２—羟乙基）烷基酰胺二（琥珀酸单酯磺酸二钠）［简称ＤＨＥＡＡＤＳＳ］，将其试用于浸酸铬鞣，发现二者均有良好的助鞣效果，但ＤＨＥＡＡＤＳＳ的助鞣性能要优于ＨＥＡＡＳＳ。     

基于FTE的两性磷酸酯加脂剂的制备及应用(续)

以高级脂肪酸、三乙醇胺和五氧化二磷为主要原料,制备了系列基于脂肪酸三乙醇胺酯类(FTE)的两性磷酸酯加脂剂(APF),测试了产物的乳液粒径、乳液稳定性及等电点等。将其应用于皮革加脂工序,测试成革的抗张强度、撕裂强度及柔软度等性能,并与市售磷酸酯加脂剂加脂后的革样进行对比。结果表明:APF系列加脂剂的乳液平均粒径在50～200 nm,以月桂酸和软脂酸为原料合成的APE加脂剂乳液静置24 h未出现分层;APF系列加脂剂的等电点在2.5～4.3,加脂助染性能优良。由软脂酸制备的APF加脂剂加脂助染性能最优,由其加脂坯革的抗张强度、撕裂强度及柔软度分别达到12.95 N/mm~2、63.44 N/mm、8.55 mm,上染率及K/S值分别达到97.52%、12.37。     

十六醇磷酸酯Gemini表面活性剂的加脂性能

以十六脂肪醇、POCl_3和二元醇为原料制备了16-m-16系列(m=2,4,6,10)十六醇磷酸酯Gemini表面活性剂,并对其性能进行测定。将其应用于绵羊蓝湿革的加脂工序,以加脂坯革纤维的接触角、吸水率、机械强度等为考察指标,与十六醇磷酸单酯(P-16)进行对比,探讨了系列产物加脂特性与结构之间的相关性。结果表明:系列产物的表面张力都较低,乳化力基本一致,随着联结链的增长,加脂坯革纤维的防水性逐步降低,物理机械强度逐渐递增,均优于P-16加脂后的坯革;系列产物加脂后的坯革的透气性、透水汽性、柔软度等方面与磷酸酯Gemini表面活性剂系列产物基本接近,也均优于P-16加脂后的坯革。     

葵花籽油磷酸酯盐型加脂剂的复配及应用

以内蒙古自治区丰富的葵花籽油为原料,采用甲醇改性,将改性油与乙醇胺进行酰胺化反应,而后与磷酸化试剂进行磷酸化反应,中和,制得新型表面活性剂—葵花籽油烷醇酰胺磷酸酯盐。通过单因素试验和正交试验法,确定了各步的最佳工艺参数。然后,将制得的烷醇酰胺磷酸酯盐表面活性剂再辅以其它助剂,制取了一种具有优良加脂性能的复合型磷酸酯类皮革加脂剂,并对加脂后革的理化指标进行检测,结果证明:加脂后革的抗张强度和断裂负荷伸长率,都优于复配组分中加脂性能较好的亚硫酸化蓖麻油处理后的革,而且符合标准(QB/T 1872—2004)值。     

基于FTE的两性磷酸酯加脂剂的制备及应用

以高级脂肪酸、三乙醇胺和五氧化二磷为主要原料,制备了系列基于脂肪酸三乙醇胺酯类(FTE)的两性磷酸酯加脂剂(APF),测试了产物的乳液粒径、乳液稳定性及等电点等。将其应用于皮革加脂工序,测试成革的抗张强度、撕裂强度及柔软度等性能,并与市售磷酸酯加脂剂加脂后的革样进行对比。结果表明:APF系列加脂剂的乳液平均粒径在50～200 nm,以月桂酸和软脂酸为原料合成的APE加脂剂乳液静置24 h未出现分层;APF系列加脂剂的等电点在2. 5～4. 3,加脂助染性能优良。由软脂酸制备的APF加脂剂加脂助染性能最优,由其加脂坯革的抗张强度、撕裂强度及柔软度分别达到12. 95 N/mm~2、63.44 N/mm、8.55 mm,上染率及K/S值分别达到97. 52%、12. 37。     

食品添加剂不饱和脂肪酸单甘酯的测定与表征

建立了食品添加剂不饱和脂肪酸单甘酯定性表征和定量分析方法。采用气相色谱-质谱法对不饱和脂肪酸单甘酯和甘油进行定性、定量分析,结果表明:不饱和脂肪酸单甘酯主要含有5种脂肪酸,即十六烷酸(棕榈酸)、十八碳二烯酸(亚油酸)、十八碳烯酸(油酸)、十八烷酸(硬脂酸)、二十二烷酸(山嵛酸)。     

New gelification method for vegetable oils I: cosmetic application

A new gelification process of vegetable oils was developed using a cellulose derivative in order to obtain transparent oleogels (anhydrous gels based on fatty components) of different consistencies. The study of their structure has been carried out by infra-red spectroscopy, differential thermal analysis and X-ray diffractometry. All these physical tests have demonstrated the gel structure of the formulations. Finally, a rheological study was run to elucidate their specific properties and their stability during storage.     

Blackberry Juice and Wine: Processing and Storage Effects on Anthocyanin Composition, Color and Appearance

Blackberry wine was made from thawed fruit (Evergreen variety) by fermentation of pulp, depectinized juice, and high-temperature short-time (HTST)-treated and depectinized juice. The effects of fining and storage on pigment composition, color and appearance were investigated. Seven anthocyanin pigments (cyanidin-3-glucoside, cyanidin-3-rutinoside, a xylose-cyanidin derivative, two acylated cyanidin derivatives, cyanidin and a polymeric derivative) were detected in the juices and wines by HPLC. Cyanidin-3-glucoside was highly unstable during fermentation. Haze development and sediment formation occurred, and 85 to 100% of total anthocyanins degraded. Blackberry juice that had been HTST-pasteurized, depectinized and fined produced wine with the most stable color and best appearance after storage.     

Assessment of coating tomato fruit with shrimp shell chitosan and N,O-carboxymethyl chitosan on postharvest preservation

The effect of coating tomato fruit (Lycopersicon esculentum) with shrimp shell chitosan, a deacetylated form of chitin, and a chitosan derivative, i.e. N,O-carboxymethyl chitosan (NOCC) on postharvest preservation was studied. The effects of various chitosan and NOCC concentrations on fruit ripening behavior, as well as fruit physical and chemical characteristics were evaluated during storage at room temperature (25–30 °C). Coating the fruit with 2 % (w/v) chitosan or NOCC solutions was found to be more effective in extended its storage life than coating with 0.5 % (w/v) solutions. Covered tomatoes were firmer, higher in titratable acidity, and exhibited less red pigmentation than the control uncoated fruits at the end of storage. These results suggest the suitability of chitosan and its derivative NOCC as an alternative means of preserving fresh fruits.     

SIMULATING VISCOELASTIC PROPERTIES OF SELECTED FOOD GUMS AND GUM MIXTURES USING A FRACTIONAL DERIVATIVE MODEL

A four parameter semi-empirical model has been developed using the fractional derivative (FD) theory, which consists of applying a mathematical operator to a constitutive equation. The Fourier transform approach is used to obtain the analytical function of the derived model. Since a single four parameter model can predict both storage modulus (G') and dynamic viscosity (η'), the developed FD model was appropriate in describing the viscoelastic properties of selected food gum dispersions, food gum mixtures and gellan gel. This fractional derivative model shows good simulation capability for selected food gum dispersions (0.5% xanthan gum, 0.5 and 0.75% locust bean gum, and 0.5, 0.75, and 1.0% guar gum), 0.6% gellan gel, and binary mixtures of carrageenan and guar gum, car-rageenan and xanthan, as well as guar and xanthan gum.     

基因、灌溉和贮藏对小麦蛋白质理化特性影响的研究进展

蛋白质理化特性是衡量小麦制品品质的重要指标,其受小麦品种、灌溉条件、籽粒和面粉贮藏时间及温湿度的显著影响。高分子量谷蛋白亚基表达量与蛋白质理化特性正相关。灌溉条件显著影响小麦蛋白质理化特性,适当的节水处理有利于蛋白质积累和麦谷蛋白大聚体大颗粒形成。贮藏时间和温湿度均显著影响小麦蛋白质理化特性;短期贮藏中,贮藏时间与麦谷蛋白大聚体理化特性正相关;随贮藏时间的延长,麦谷蛋白大聚体含量和面团黏弹性逐渐降低;与低温低湿条件相比,高温高湿条件下小麦各指标在贮藏过程中变化幅度大。后期可结合籽粒和面粉贮藏及麦谷蛋白大聚体流变学特性和形貌开展研究,以期为籽粒和面粉贮藏质量,乃至面制品质量控制提供理论依据。     

方便米饭老化特性研究

研究了方便米饭存放过程中的老化特性,结果表明：方便米饭在存放过程中晶体结构有所变化,但结晶度变化不大;起始玻璃化温度上升,玻璃化温度范围缩小,晶体熔解温度稍有上升;复水扩散系数下降,起始玻璃化温度的升高对扩散系数的影响较大,存放10天后,起始玻璃化温度是影响方便米饭速食性能和老化的主要因素。     

Microencapsulation of caraway extract in β-cyclodextrin and modified starches

Microencapsulation of supercritical CO₂ extracted caraway fruit oil was investigated. Encapsulation was carried out by molecular inclusion with #-cyclodextrin, by spray-drying with maltodextrin and by spray-drying with a starch derivative. Carvone, one of the two main constituents of caraway essential oil, was efficiently complexed with #-cyclodextrin. Only half of the other major constituent, limonene, was complexed. The inclusion complex seemed to protect volatile substances more efficiently during storage, whereas microcapsules with modified starches as wall material were more heat tolerant. During rapid heating, the #-cyclodextrin microcapsules protected the volatile substances from evaporation up to 100 °C and HiCap microcapsules protected them up to 140 °C, while the protection properties of the maltodextrin microcapsules seemed to depend on the encapsulated molecules (160 °C for limonene and 120 °C for carvone).     

NaCl对冻藏期间冰全蛋功能性质的影响

为改善冰全蛋的功能性质,开发专用型冰全蛋产品,以鲜蛋为原料,研究了6 个月冻藏期内不同添加量NaCl（0.5%、1%、2%和4%）对冰全蛋功能性质的影响,并结合理化性质的变化对其原因进行分析。结果发现,冰全蛋表面疏水性随冻藏时间延长和NaCl添加量的增加而升高,而总巯基和表面巯基含量均随冻藏时间的延长而降低,但随NaCl添加量的增加呈现复杂变化。冰全蛋的溶解度随冻藏时间的延长而降低,添加1%和2%的NaCl冰全蛋的溶解度明显高于空白组;随冻藏时间的延长,冰全蛋的起泡性整体呈下降趋势,泡沫稳定性整体呈上升趋势,其中添加2%的NaCl可以显著改善冰全蛋的起泡性,60～180 d后起泡性仍优于未冻藏未加盐冰全蛋,且优于鲜蛋。同时,凝胶强度及凝胶持水性均在冻藏初期增加而后持续下降,添加1%的NaCl可以显著改善冰全蛋的凝胶性,30 d后凝胶性仍高于未冻藏未加盐冰全蛋,且高于鲜蛋。所以添加一定量的NaCl可改善冰全蛋的功能性质,为开发专用型冰全蛋的生产提供理论指导。     

Antioxidative effect of crackling hydrolysates during frozen storage of cooked pork meatballs

The effect of acid (CAH) and enzymatic (CEH) hydrolysates prepared from pork cracklings on the oxidative stability of frozen pork meatballs was investigated. Meatballs were stored at −18 °C for 180, 270 and 360 days during which time peroxide value (PV), TBARS, profiling sensory analysis and cholesterol oxidation products (COPs) were determined. The oxidation products of cholesterol, such as epimers 7-hydroxy, 5,6-epoxy, 7-keto, triol and 25-hydroxy, after transesterification and SPE fractionation, were detected by capillary gas chromatography. CAH and CEH possessed similar antioxidant efficacy. Inhibition activity of cracklings hydrolysates against PV was 38–45%, and against TBARS was 30–39%. The antioxidant properties of CAH and CEH against the oxidation of lipids were poorer than that of BHT. The addition of hydrolysates changed sensory profiles and had a significant (P<0.05) effect on the taste and odour of meatballs. The total COPs in all meatballs increased during storage. 7-Keto-cholesterol was the dominant oxysterol in fresh samples. After 360 days of storage, levels of oxysterols in samples treated with hydrolysates were about 20% lower than that of the control sample. The most toxic derivative, triol-cholesterol, was detected at the lowest level in samples treated with hydrolysates. The protection of BHT against cholesterol oxidation was poorer than that of CEH.     

The effect of acid and glucoamylase hydrolysis on partial physicochemical properties and characteristics of Dioscorea alata Linn. starch

Dioscorea alata Linn. (D. AL) rich in starch was widely used as food and medicine. This work aimed to compare the effect of acid and glucoamylase on the starch of different reaction time. The physicochemical properties of the native and hydrolyzed starches, such as swelling power (SP), starch solubility (SOL), and paste clarity were also determined in this study. The native and modified starches by acid and glucoamylase were compared and characterized by scanning electron microscope (SEM) and secondary derivative FT‐IR spectroscopy. The morphological characteristics of native D. AL starch granules revealed by SEM varied from round to oval or elliptic with smooth surface. SEM showed that glucoamylase primarily attacked the exterior of starch granules and permeate into the interior by the cracks formed on the surface. Owing to acid hydrolysis, the starch granules were depressed and transformed to bread‐like in shape and then broke into irregular lumps with particles adhered. From secondary derivative FT‐IR spectrum, the intensities of the two peaks from acid and enzyme hydrolysis starches at 1137 and 1066/cm were stronger than native starch. Some new peaks appeared due to hydrolysis. The digested starches exhibited a lower SOL and SP than native starch in water as the temperature increasing. The light transmittance of the digested starches was significantly higher than that of native starch paste and decreased with increase in storage period.