粥化酶及其在果蔬加工中的应用研究

研究了粥化酶的粗酶特性及其在果蔬加工中的应用，并比较了粥化酶与其它果蔬加工用酶在苹果加工中的应用效果。研究结果表明粥化酶作用的最佳条件符合果蔬加工的要求，它能够不同程度的提高果蔬的出汁率及其澄清度；与其它果蔬加工用酶相比粥化酶具有作用效果好，价格便宜的优点     

青椒果实冷害及诱导抗冷性与氧化胁迫关系的研究

青椒在9℃下冷藏8w，没有出现冷害，膜透性变化不大。而在2℃下贮藏1w后即出现冷害症状，超过4w发生严重冷害，膜透性迅速上升。与9℃贮藏青椒相比，2℃贮藏青椒的SOD活性降低，而CAT活性降低更多；POD活性也低于9℃贮藏青椒，但7w时骤升至峰值。贮前50℃10min或53℃5min热水浸泡处理极显著降低了2℃贮藏青椒的冷害，显著抑制了膜透性的上升。与对照相比，50℃热处理对青椒SOD活性影响不明显而53℃热处理显著提高了3、4和5w时SOD活性。两热处理均极显著提高了青椒CAT活性，对CAT活性的提高超过SOD。两热处理青椒贮藏过程中POD活性呈缓慢下降趋势，避免了对照组青椒POD活性6w时的显著降低和7w时的骤然上升。可见青椒的冷害与低温下活性氧清除酶，特别是CAT活性的降低，导致活性氧化代谢失调有关。而贮前热处理通过提高活性氧清除酶特别是CAT活性，维持活性氧代谢的平衡，抑制膜质过氧化，从而减轻了青椒的冷害。     

桑葚花色苷提取、纯化和生理活性研究进展

桑葚花色苷是一种存在于桑葚中的水溶性色素,属类黄酮化合物,不但可以用于食品着色,而且对人体有多种生理保健功能。对桑葚花色苷的提取、分离纯化、分子结构、稳定性、生理活性的最新研究成果进行综述,为桑葚花色苷的开发利用提供参考和依据。     

桑叶生物碱对小鼠酒精性肝损伤的保护作用

探讨桑叶生物碱（mulberry leaf alkaloids,MLA）对酒精性肝损伤小鼠的改善作用。建立酒精性肝损伤小鼠模型,以MLA（40、80、160 mg/kg?day）干预4周,计算肝脏指数,检测血清甘油三酯（TG）、总胆固醇（TC）、谷丙转氨酶（ALT）、谷草转氨酶（AST）和肝脏中过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GSH-Px）、总超氧化物歧化酶（SOD）、丙二醛（MDA）、肿瘤坏死因子α（TNF-α）、白细胞介素1β（IL-1β）、白细胞介素6（IL-6）的含量。与模型组相比,MLA中剂量组小鼠的肝脏指数、血清TG、TC、ALT、AST和肝脏MDA、IL-1β、IL-6、TNF-α水平分别降低11.18%、22.78%、19.19%、28.08%、16.16%、25.07%、23.51%、18.61%、11.78%,肝脏SOD、CAT、GSH-Px活力分别提高27.47%、15.36%、27.83%;MLA高剂量组小鼠的肝脏指数、血清TG、TC、ALT、AST和肝脏MDA、IL-1β、IL-6、TNF-α水平分别降低15.17%、32.65%、23.16%、30.58%、16.41%、31.97%、27.19%、25.41%、29.59%,肝脏SOD、CAT、GSH-Px活力分别提高38.38%、19.09%、31.09%;MLA中、高剂量组肝脏组织结构损伤明显改善。MLA可以改善小鼠酒精性肝损伤,其作用机制可能与改善肝脏氧化应激和抑制炎症反应有关。     

Recent developments in cold plasma-based enzyme activity (browning,cell wall degradation,and antioxidant) in fruits and vegetables

According to the Food and Agriculture Organization of United Nations reports, approximately half of the total harvested fruits and vegetables vanish before they reach the end consumer due to their perishable nature. Enzymatic browning is one of the most common problems faced by fruit and vegetable processing. The perishability of fruits and vegetables is contributed by the various browning enzymes (polyphenol oxidase, peroxidase, and phenylalanine ammonia-lyase) and ripening or cell wall degrading enzyme (pectin methyl-esterase). In contrast, antioxidant enzymes (superoxide dismutase and catalase) assist in reversing the damage caused by reactive oxygen species or free radicals. The cold plasma technique has emerged as a novel, economic, and environmentally friendly approach that reduces the expression of ripening and browning enzymes while increasing the activity of antioxidant enzymes; microorganisms are significantly inhibited, therefore improving the shelf life of fruits and vegetables. This review narrates the mechanism and principle involved in the use of cold plasma technique as a nonthermal agent and its application in impeding the activity of browning and ripening enzymes and increasing the expression of antioxidant enzymes for improving the shelf life and quality of fresh fruits and vegetables and preventing spoilage and pathogenic germs from growing. An overview of hurdles and sustainability advantages of cold plasma technology is presented.     

桑果醋发酵工艺研究

以桑果、糯米为原料，采用液态发酵法，酿制风味独特、营养丰富的桑果醋。通过对桑果汁压榨、浸提、澄清和酒精发酵、醋酸发酵等工艺的研究，确定桑果汁酶解澄清的最佳方案是：果胶酶添加量为0．035％、淀粉酶0．014%、明胶0．018％、硅溶胶0．018％；确定主要工艺参数为：酒精发酵阶段桑果清汁：糯米糖化醪=2：1，接种量5％，25℃发酵72h，酒精浓度6．0％，醋酸发酵阶段温度为33℃-35℃，接种量6．0％，起始pH6．0，500mL三角瓶装液量100mL，在转速140r／min条件下振荡培养72h左右，得到的成品醋酸度适宜，口感、风味良好。     

Internal Modified Atmospheres of Coated Fresh Fruits and Vegetables: Understanding Relative Humidity Effects

ABSTRACT: Internal atmosphere modification in fruits and vegetables by surface film coatings depends on film permeability, coating thickness, and fruit surface coverage. Research in this area has been mostly empirical, with unpredictable results and diverse conclusions. To reduce variability, it is necessary to have a better understanding of factors that may influence the response of coatings applied to fruits. One factor is relative humidity (RH), which is known to affect the permeability of biopolymer films. By using steady-state mathematical models as tools, we hypothesize that fruits coated with hydrophilic films will be largely influenced by the RH of storage conditions. For hydrophobic materials, RH would have less influence on coating performance.     

乙烯基硅氧烷单体接枝家蚕丝的性能研究

采用新型乙烯基硅氧烷单体对家蚕丝接枝改性，通过红外光谱和扫描电镜分析，接枝单体足依靠物理沉积和化学键作用与纤维结合的。接枝后真丝织物的折皱回复性显著提高，手感更为柔软，且小影响家蚕丝的强度。接枝后家蚕丝的白度和染色性略有下下降，染色色牢度与未处理真丝织物基本相同。     

桑叶染色液提取法与染色性能

 为了探索提取方法和提取剂对桑叶染色液染丝绸的效果,采用沸水浴与微波法提取桑叶染色液,结果表明:染色液中的黄酮含量及对丝织物的上染率均以微波法较高。采用微波提取法,通过正交试验研究提取剂对上染率和色光的影响,结果表明对上染率影响最大的是表面活性剂用量,其次为NaOH浓度,再次为表面活性剂种类;对色光影响的次序是NaOH浓度大于表面活性剂用量和种类。采用微波提取法并在NaOH提取剂中加入表面活性剂的桑叶染色液染色效果较好。