酶法提取树莓汁的研究

以澳洲红、早红、美国22三个品种树莓为原料,通过不同的酶处理方法来制取原果汁,优选适于制汁的品种和酶处理方法.     

破壁方法对红球菌11-3胞内几丁质脱乙酰酶释放的影响

红球菌11-3是一株高产几丁质脱乙酰酶(CDA)的菌株，几丁质在该酶的催化作用下可转化为壳聚糖，该酶在壳聚糖的生产中具有重要作用。红球菌11-3菌株所产CDA为胞内酶，成为催化反应的一大障碍。为了提高CDA的释放率，本研究首先利用不同的物理方法(反复冻融、超声、球磨、匀浆和液氮研磨)、化学方法(表面活性剂处理、氯仿处理)和生物学方法(溶菌酶处理)对红球菌11-3进行破壁处理，测定CDA酶活力和释放率，并通过扫描电子显微镜观察细胞形态变化。结果表明，不同方法的破壁效果存在很大差异，其中，液氮研磨法破壁效果最佳，菌体表面出现细密的孔洞，CDA释放率为45.13%，总酶活力损失率为2.03%；匀浆处理法次之，CDA释放率为16.00%，总酶活力损失率为9.18%。利用匀浆和液氮研磨联合处理红球菌11-3细胞，细胞表面产生更多、更大的孔洞，CDA释放率高达86.17%，总酶活力损失率为9.11%，上清液中CDA酶活力为480.2 U/mL，较液氮研磨法相比提高了1.48倍。结论:匀浆和液氮研磨联合处理可有效破坏红球菌11-3细胞壁，提高胞内CDA释放效率。本研究结果对红球菌11-3内CDA应用于壳聚糖的生产具有参考作用。     

树莓澄清果汁的加工工艺

研究了红树莓澄清果汁的加工工艺,酶解处理的酶用量,酶解温度,酶解时间的单因素试验以及酶用量,酶解时间和红树莓品种的正交优化试验表明,树莓果浆经酶解后,出汁率有较大提高,果汁澄清度也较好。最佳酶处理条件为加酶量3.5‰,酶处理温度45℃,时间4h;在所试验的3个品种中,维拉米综合指标最好,表现为出汁率高,可溶性固形物,总糖,VC含量均较高;树莓汁调配时一般不需加酸,只需补充糖即可达到较好的口感风味。     

变性淀粉在红肠中的应用研究

变性淀粉是天然淀粉经物理、化学或酶处理后,改变了理化性质而制得的一类淀粉.用变性淀粉代替天然淀粉添加到红肠中,可明显提高红肠的弹性和粘聚性,降低硬度和咀嚼性,对红肠的质构特性有明显改善.     

变性淀粉在哈尔滨红肠中的应用研究

变性淀粉是天然淀粉经物理、化学或酶处理后,改变了理化性质而制得的一类淀粉。用变性淀粉代替天然淀粉添加到哈尔滨红肠中,可明显提高红肠的弹性和粘聚性,降低硬度和咀嚼性,对哈尔滨红肠的质构特性有明显改善。     

复合酶解制作红树莓汁工艺的优化及抗氧化研究

目的 优化红树莓酶解制汁工艺,并探究其抗氧化性。方法 以出汁率为指标,采用单因素实验及响应面法优化复合酶解红树莓制汁工艺条件,使用DPPH ·自由基清除能力、ABTS＋·自由基清除能力 、总还原力3种方法评价红树莓汁抗氧化性。结果 复合酶解制备红树莓汁的最优工艺参数为果胶酶、纤维素酶和半纤维素酶的质量比为5:4:1 ,酶添加量0.15%,酶解温度47 ℃,酶解时间59 min,此条件下红树莓出汁率达到86.10%;酶解后活性成分含量较原汁相比显著增加,红树莓汁具有较强的体外抗氧化活性,其总酚含量与DPPH·自由基清除能力、ABTS＋ ·自由基清除能力 和总还原力的线性相关系数分别为0.966、0.970、0.978,且黄酮和花色苷在总酚的抗氧化性上起主要贡献作用。结论 在最佳酶解条件下制备的红树莓汁出汁率较高,且抗氧化性强,本研究可为红树莓系列功能性产品的开发提供参考。     

复合风味蛋白酶水解豆粕调味液的研究

本以豆粕为原料，以天然复合风味蛋白酶为水解剖，对豆粕的酶解条件进行了5因素4水平正交实验研究。结果表明，最佳酶解条件为：加酶总量为原料豆粕量的11％；底物豆粕浓度为14％；酶解时间16h；高温处理温度为121℃；时间25nim。在此条件下所制得的调味液色泽栋红，口感鲜美，无苦涩等异味，无毒副产物形成，氨基态氮可达0．54％，是一种高级营养调味品。     

美国红鱼酶解重组灌肠工艺研究

本实验介绍美国红鱼经过复合酶制荆酶解后，红鱼肉中的蛋白质及各种营养成分的价值都得到了提高，通过优化生产工艺条件，确定了红鱼肉重组加工生产的无衣灌肠的最佳加工工艺条件。     

酶法液化制汁与果汁化学成分的相关性

本试验以苹果、草莓、山楂、枣等原料，对酶法液化制汁为果汁化学成分含量的相关关系进行了研究。结果表明，采用酶法液化法制汁与传统方法制汁比较，可提高出汁率，可溶性固形物，总糖、总酸的含量，并可显著提高混汁纤维素的含量，具有良好的酶效应，提高果汁总糖量和出汁率的酶效应，受加酶量，处理温度和时间的影响。     

不同胡萝卜品种制脯效果的研究

采用真空浸糖结合传统糖煮方法,以甘谷黄、德斯坦、丹富士及鞭杆红等胡萝卜品种为原料．制成优质果脯．并测定了制脯前后的感官及理化指标。结果表明在不加任何着色剂条件下,不同品种制脯后具有不同的天然色泽,可有不同用途。胡萝卜制脯后较未制脯前,胡萝卜素含量变化较大,但不同品种的损失率有明显差异。在供试品种中,损失率最大的品种是甘谷黄为62．5%,损失率最小的品种是丹富士,仅20．6%。经全面分析比较后认为,以丹富士品种制脯可以生产出最佳产品。     

漆酶处理对未漂APMP浆性能的作用

研究漆酶NS51003对未漂APMP浆性能的影响,探讨漆酶处理温度、时间及酶用量对纸浆白度及强度性能的影响。结果表明:在最佳的实验条件下漆酶处理可以提高纸浆的强度性能,白度稍有下降。漆酶处理主要作用于纤维表面的木素。     

制浆造纸废水处理新技术

随着制浆造纸工业的发展以及人们对环保意识的不断提高,要求造纸废水排放需达到GB3544—2008排放标准,因此,制浆造纸废水处理新技术的研究及应用成为热点。本文主要介绍了酶处理、复合仿生酶处理、营养剂生物处理等生物新技术以及高级氧化技术、新型膜技术在深度处理制浆造纸废水中的研究与应用情况,以期对今后制浆造纸废水处理提供有价值的参考。     

亚麻纤维素酶整理工艺的探讨

以纤维素酶对亚麻纤维进行整理，探讨酶处理温度、时间、pH值对酶整理失重率的影响，确定了最佳工艺条件及参数。讨论了酶整理后pH值对亚麻纤维断裂强度及白度性能指标的影响。     

Effect of direct-fed fibrolytic enzymes on the lactational performance of dairy cows

In trial 1, 30 midlactation (213 d in milk) Holstein cows were randomly assigned to a control or enzyme treatment in a two-period crossover design and were fed a total mixed ration based on alfalfa hay and silage. Cows on the enzyme treatment received an enzyme solution containing cellulases and xylanases, which was sprayed on the forage component of the ration at a rate of 1.65 ml/kg of forage dry matter (DM) between 8 and 24 h prior to feeding. Cows consuming the forage treated with enzyme produced more milk (27.2 vs. 25.9 kg/d) and digested more DM per day than did cows fed the control forage. In trial 2, 40 early lactation Holstein cows were assigned to one of four treatments for 16 wk. Following a 2-wk covariate period, cows were assigned to 1) no enzyme treatment, 2) a low (1.25 ml/kg of forage DM) enzyme treatment, 3) a medium (2.5 ml/kg of forage DM) enzyme treatment, or 4) a high (5.0 ml/kg of forage DM) enzyme treatment. Enzymes were a 2:1 combination of cellulase and xylanase diluted in water and sprayed on a combination of alfalfa hay and silage and whole cottonseed immediately before mixing with a concentrate based on barley. Dry matter intakes were similar for cows on treatments 2, 3, and 4 and were greater than those for cows on treatment 1. Production of milk, 3.5% fat-corrected milk, and energy-corrected milk was greater for cows on treatment 3 than for cows on treatment 1. Fibrolytic enzymes applied to the forage portion of the rations prior to feeding improved lactational performance of early and midlactation cows.     

彩棉/亚麻/白棉混纺针织物酶前处理工艺研究

采用精练酶对彩棉／亚麻／白棉混纺针织物进行处理，分析了酶用量、pH值、温度和时间等因素对精练酶精练效果的影响，并进一步采用正交实验优化了精练酶处理工艺参数。     

Effect of High-Pressure Treatment on the Molecular Properties of Mushroom Polyphenoloxidase

To elucidate the mechanism of pressure-induced denaturation of mushroom polyphenoloxidase (PPO), the enzyme was treated under 600 and 800 MPa, respectively, and its molecular properties such as secondary and tertiary structure were examined. High-pressure inactivation of the enzyme increased with pressure level and treatment time. Circular dichroism study showed that high-pressure treatment decreased the negative ellipticity values in the range 210-225 nm, resulting in change of the secondary structure of the enzyme. Fluorescence emission intensities also decreased with increase of high pressure and processing time, indicating changes in the tertiary structure of the enzyme. This study clearly shows that high-pressure treatment significantly alters the molecular properties of the enzyme.     

苎麻生物酶脱胶工艺研究

主要研究了苎麻的生物酶脱胶工艺。将生物酶脱胶后的精干麻与传统化学脱胶精干麻进行性能对比,得出生物酶脱胶精干麻的残胶率、断裂强力、柔软性均高于化学脱胶法,生物酶脱胶工艺煮液的COD值明显低于化学脱胶法的,对环境的污染小。通过正交试验得出苎麻生物酶脱胶的最佳工艺条件为SC0URZYME301用量15％,温度50℃,浸酶时间2h,堆置时间16h。     

制备Lyocell纤维用纤维素浆粕的碱性酶处理工艺

为提高Lyocell纤维制备过程中纤维素的溶解效率和溶液稳定性,分别改变碱性酶处理Lyocell纤维用纤维素浆粕的时间和用量,研究其对浆粕相对分子质量和可及度的影响,并对处理工艺进行优化。结果表明:酶处理后纤维素晶型没有受到破坏,仍是典型的纤维素I型构象;当酶用量为4 000 mL/t,增加处理时间至60 min时,纤维素浆粕的聚合度降为430并趋于稳定;当处理时间为60 min,增加酶的用量至2 000 mL/t时,纤维素浆粕的聚合度由520降低至约430,相对分子质量分布变窄;经过纤维素酶处理后纤维素浆粕的可及表面积有所增加,但晶体结构未发生变化,纤维素酶主要是作用于纤维素分子的无定形区和结晶表面较差有序部分。     

Effects of in-feed enzymes on milk production and components,reproduction, and health in dairy cows

Our objectives were to characterize responses in the field to a mix of fibrolytic enzymes using large commercial dairy herds and sufficient study power to evaluate milk production and reproductive responses to an enzyme treatment started during the precalving period. We hypothesized that the use of the enzyme treatment would increase milk production when provided to dairy cows precalving and for approximately 200 d of lactation. The study was conducted on 7,507 cows, in 8 replicates and 16 pens, at 3 dairies in the United States. Eight pens were randomly allocated as control pens and received no enzyme, and another 8 pens received enzyme treatment at a dose of 750 mL/t of dry matter feed. Milk production and energy-corrected milk yield were increased with the enzyme treatment by 0.70 and 0.80 kg/d, respectively, across a 5-month period. Milk fat percentage was not significantly increased by enzyme treatment, but milk fat yield was significantly increased by 0.040 kg/d, compared with controls. Milk protein yield increased 0.010 kg/d with enzyme treatment despite a small reduction of 0.020 percentage units in milk protein percentage. We found no evidence of an increase in the ln somatic cell count for the enzyme-treated cows. Body weight overall was not increased for enzyme-treated cows, but we did observe a numerical increase in dry matter intake (0.20 kg/head per day) for enzyme-treated cows. Most production responses to the enzyme treatment were influenced by dairy. Compared with controls, milk yield in enzyme-treated cows was significantly higher by 3.6 kg/d in dairy 2 and numerically higher by 0.60 and 0.20 kg/d in dairies 1 and 3, respectively. Reproduction, health, and risk of removal or death were not significantly influenced by treatment, apart from a reduced time to first breeding. Production responses to the enzyme treatment varied by dairy from substantial to minor increases, but variation among dairies was not evident in differences in dry matter intake or in partitioning of body weight among enzyme-treated and control pens and cows. It appears likely that the increase in production reflected increased digestibility of feed; however, further work is needed to identify factors influencing the variation in production responses to enzymes.     

棉纤维碱性果胶酶处理工艺的探讨

棉散纤维前处理是色纺产品的关键工序。描述了棉纤维的传统碱处理和酶处理的多次试验。分析了实验的结果。通过效果测试,初步得出适合棉纤维的酶处理工艺。