油酸、三油酸甘油酯CRC模拟物对新闻纸湿部化学特性的影响

采用了一种机械分散方法制得了呈胶体态的树脂成分(CRC,Colloidal Resin Component)模拟物,并考察了模拟物对新闻纸抄造常用助留体系(PEO/PFR,PEI/CPAM)的影响.着重分析了油酸模拟物、三油酸甘油酯模拟物对系统中Zeta电位、阳离子需求量和一次留着率等参数的影响,并对两种模拟物的影响机理进行了探讨.     

不同壁材组合对三丁酸甘油酯微胶囊性质的影响

为拓宽三丁酸甘油酯的应用范围,以三丁酸甘油酯为芯材,抗性糊精-明胶-海藻酸钠（RGS）、抗性糊精-明胶-海藻酸钠-月桂酸单甘酯（RGSG）、抗性糊精-明胶-壳聚糖（RGC）、抗性糊精-明胶-壳聚糖-月桂酸单甘酯（RGCG）为壁材,采用喷雾干燥法制备4种微胶囊,对微胶囊包埋率及产率、粒径分布、基本理化性质、颜色、结构特征及外观形貌进行分析,探究不同壁材对三丁酸甘油酯微胶囊性质的影响。结果表明：RGSG微胶囊包埋率（91.05%）及产率（90.46%）较高;与RGC、RGS微胶囊相比,RGSG、RGCG微胶囊的水分活度、粒径分布、流动性、吸湿性、亮度均有一定的改善;红外光谱及扫描电镜结果表明三丁酸甘油酯被壁材有效包埋起来,其中RGSG、RGCG微胶囊形成了更强的氢键。综上,RGSG制备的微胶囊综合性质优于其他3种壁材。     

打浆对新闻纸物理性能的影响

本文研究了脱墨浆(DIP)、漂白化学预热机械浆(BCTMP)与硫酸盐浆(KP)在不同打浆度下配抄新闻纸的状况.讨论了打浆度对新闻纸物理性能的影响.     

新闻纸物理性能对彩报印刷的影响

本文介绍新闻纸物理性能好坏对彩报印刷的影响，从而说明对新闻纸质量指标控制的重要性。     

山楂果胶对酸奶物性指标影响分析

本实验以鲜乳和山楂汁为主要原料,研究了制作山楂风味凝固型酸奶的最佳配方;并对山楂汁中果胶含量进行测定与分析,确定了山楂果胶是影响山楂凝固型酸奶感官和物性指标主要因素,分析了山楂果胶对酸奶品质的影响程度。     

不同乳化剂对油酸和亚油酸乳状液稳定性的影响

本文以粒径、稳定性和流变为考察指标,利用激光粒度仪、食品稳定性分析仪、流变仪等研究不同种类和添加量的食品乳化剂(阿拉伯胶、酪蛋白酸钠、吐温20)对不饱和脂肪酸(油酸和亚油酸)乳状液的制备及其稳定性的影响。结果表明,三种乳化剂均可制备出稳定性较好的乳状液,不同乳化剂的质量分数不同得到乳状液的稳定性不同。较高质量分数的阿拉伯胶(4%,w/v)乳状液,具有最低的澄清指数并且具有最大粘度(0.30~0.40 Pa·s)。当酪蛋白酸钠的质量分数为2%时,制备出的乳状液较稳定,但粒径较大,贮藏稳定性较差。较低质量分数的吐温20(1%,w/v)的乳状液具有最小粒径(0.20~0.21 μm),经过贮藏后变化程度也最小。本文研究了不同食品乳化剂制备的不饱和脂肪酸乳状液及其稳定性,可为不饱和脂肪酸乳状液的制备和应用提供参考。     

Comparison of Cheeses Made from Milk Having Normal and High Oleic Fatty Acid Compositions

Calcium salts of high‐oleic sunflower oil (> 86% oleic acid) were prepared and fed at 0% and 7.5% of diet dry matter weight to 8 Holstein cows in early‐ to mid‐lactation in a cross‐over experimental design. Oleic acid content of milk fat increased from 26% to over 40% and cholesterol‐raising saturates were reduced from 41% to 33%. Latin American white cheese, queso blanco, was produced from modified and normal milk. No differences in firmness were found between cheeses using penetration‐compression testing with an Instron machine. Sensory difference tests indicated no significant differences between cheeses. Latin American white cheeses made with high oleic milk are similar to traditional cheese.     

Effects of Dilute Acid Pretreatment on Chemical and Physical Properties of Kenaf Biomass

In the current research, kenaf represents an agricultural biomass that possesses enormous potential for industrial applications. Because of its complex structure, which is composed of cellulose, hemicellulose, and lignin, pretreatment process was conducted. Here, dilute acid pretreatment process was conducted, statistically using the response surface method, which included three parameters: mass of biomass (g), temperature (°C), and time (min). About 2 g of kenaf biomass was treated with 2% dilute sulphuric acid, and it was found to have higher glucose conversion (25.3%) when the process was conducted for 60 min at the temperature of 180°C. The main aim of the current research is to investigate the chemical and physical changes of kenaf biomass before and after the pretreatment. The changes could be clearly seen in the cellulose, hemicellulose, and lignin composition before and after the pretreatment, which were evaluated via TAPPI standard test methods. Morphological observation under scanning electron microscope confirmed the changes that took place on the kenaf biomass from complex to simple surface structure. Fourier transform infrared analysis confirmed the presence of cellulose, hemicellulose, and lignin contents of the kenaf biomass before and after pretreatment. Crystallinity of the treated kenaf biomass also increased from 46.6% to 70.0%, as evidenced from X-ray diffractometer analysis.     

油炸工艺对高油酸花生品质与微观结构的影响

研究植物油种类、油炸温度、油炸时间对油炸花生感官品质、质构特性的影响,并通过激光共聚焦扫描显微镜（CLSM）和扫描电镜（SEM）观察油炸前、后花生微观结构的变化。结果表明,油炸最佳工艺条件：植物油种类为棕榈油,油炸温度140℃、油炸时间8 min。在该工艺条件下油炸花生色泽均匀,口味香甜,口感酥脆,硬度7.30 kg,脆性0.27 mm,感官得分48.9,水分含量0.87 g/100 g、酸价1.20 g/100 g、过氧化值0.09 g/100 g,扫描电镜与激光共聚焦显微镜观察的结果一致,花生在油炸后细胞壁断裂,细胞质丢失,出现孔状结构,细胞内油体增加,蛋白体聚集。     

油酸和麦芽糖醇混合物对玉米淀粉老化特性的影响

为探究油酸和麦芽糖醇混合物抑制玉米淀粉老化的效果,通过快速黏度分析、差示扫描量热分析、质构分析、动态流变分析、低场核磁共振分析、红外光谱分析和X射线衍射分析等方法比较不同复配比例的油酸和麦芽糖醇混合物对玉米淀粉糊化特性、老化特性、流变学特性、质构及结晶结构等的影响。结果显示：添加油酸和麦芽糖醇混合物后,玉米淀粉的糊化温度升高,回生值和老化速率降低,且当油酸和麦芽糖醇质量比为0.5∶1.5时,糊化温度最高（77.80 ℃）,回生值最低（1 218 cP）,老化速率比原淀粉降低了60%;油酸和麦芽糖醇混合物的添加能增大玉米淀粉的损耗角正切值和横向弛豫时间（T2）,形成较弱的凝胶结构,降低玉米淀粉凝胶的硬度、短程有序度和相对结晶度;当油酸和麦芽糖醇为0.5∶1.5质量比复配时,混合物对延缓玉米淀粉老化存在协同作用。这可能与麦芽糖醇能抑制淀粉体系中水分子运动、油酸能与淀粉形成淀粉-脂质复合物从而有效抑制淀粉重结晶有关。研究结果可为改善玉米淀粉加工特性、提高淀粉基食品品质提供一定的理论依据。     

辛癸酸甘油酯和橄榄油的极性调控研究

本文以添加了不同浓度表面活性剂司盘80(Sp80)的辛癸酸甘油酯(Octanoic acid glyceride,ODO)和橄榄油作为模型油脂,测定在不同剪切速率下ODO和橄榄油的表观黏度,分析不同司盘80添加量对ODO和橄榄油界面张力的影响,并对其抗聚并稳定性进行了评价,从而探讨不同浓度表面活性剂下油脂极性的变化规律。结果表明,ODO和橄榄油体系的表观黏度随司盘80添加量的增加而增大;当司盘80浓度小于5%时,ODO-水界面张力降低,ODO极性增大;而在橄榄油体系中,橄榄油-水的界面张力达到平衡所需司盘80用量较ODO少,当司盘80浓度大于1%时,橄榄油极性与界面张力无明显变化,且司盘80可增强ODO和橄榄油油滴的抗聚并稳定性;当司盘80浓度大于5%时,由于油相极性较大,油水间作用力增强且过量胶束生成,反而促进了橄榄油油滴的聚并。     

抗坏血酸改性大豆7S球蛋白物化特性研究

研究了抗坏血酸改性大豆7S球蛋白对体系粘度、发泡性、发泡稳定性、乳化性、乳化稳定性的影响。结果表明：7S球蛋白的感官质量优于大豆分离蛋白；0．8％的抗坏血酸改性7％的7S球蛋白，其粘度最大，达到39．5MPa．s；7S球蛋白溶液浓度为5％、加入0．4％的抗坏血酸改性，其体系的发泡性能最佳，泡沫体积达到515mL；7S球蛋白溶液浓度为7％、加入0．4％的抗坏血酸改性，其体系的发泡稳定性最佳，达到68．9％；7％的7S球蛋白溶液采用0．8％的抗坏血酸改性，体系的乳化性能和乳化稳定性均最强。