蓝莓汁复合酶法制取工艺的优化研究

以蓝莓为原料,考察了复合酶添加量、复合酶配比、酶解温度、酶解时间4个因素对蓝莓出汁率的影响。在单因素试验的基础上,采用Box-Behnken响应面设计对复合酶酶解蓝莓汁的工艺参数进行进一步的优化。结果表明,复合酶法制取蓝莓汁的最佳工艺参数为:复合酶添加量0.20%,复合酶(果胶酶∶纤维素酶)配比3∶1(m∶m),酶解温度47℃,酶解时间84 min,该工艺条件下蓝莓出汁率达78.38%,与模型预测值78.54%相比,其相对误差约为0.20%,表明在蓝莓汁复合酶法制取过程中采用响应面试验设计对工艺参数进行优化是可行的。     

酶解对青梅汁澄清效果的影响

采用单因素试验,分别研究了果胶酶和纤维素酶澄清青梅汁的最佳工艺条件。设计复合酶澄清青梅汁的4因素3水平正交试验,以透光率和出汁率为指标,确定澄清青梅汁的最适工艺条件为:果胶酶用量为0.07%,纤维素酶用量为0.08%,酶解时间为3.5h,酶解温度为40℃,青梅汁的透光率和出汁率分别为79.43%和77.29%。     

双酶法玉米汁饮料的研制

以新鲜玉米为原料,经过粉碎、糊化等工艺处理后,对酶解的工艺进行研究,分别测定玉米汁饮料在高温α-淀粉酶和糖化酶的不同酶解条件下的DE值,以确定2种酶最佳的工艺参数。通过感官评价的方法,进一步确定蔗糖和稳定剂的添加量,保证玉米汁饮料的最佳口感以及合适的稳定效果。结果表明,高温α-淀粉酶酶解玉米汁的工艺参数为加酶量20 U/g,酶解时间60 min,酶解温度80℃;糖化酶的酶解工艺参数为加酶量200 U/g,糖化时间5 h,糖化温度60℃。选择蔗糖添加量1.0 g/100 mL时,玉米汁饮料甜度适宜、口感清爽;选择黄原胶和CMC作为稳定剂,其中黄原胶添加量0.2%,CMC添加量0.1%达到较好的稳定效果。     

酶解法制备荸荠汁工艺及荸荠银杏花生乳复合饮料的研制

采用超低温冷冻结合快速融冰技术对荸荠进行预处理,以淀粉酶处理荸荠浆液,研究酶解条件对荸荠出汁率的影响。试验结果显示,在酶添加量0.04%、酶解温度52℃、酶解时间60 min的条件下,荸荠的出汁率达到83.12%,效果较好。以荸荠汁、银杏汁和花生乳为基料,经复配获得荸荠银杏花生乳复合饮料,采用单因素及正交试验研究复合饮料的工艺配方。结果表明,荸荠汁添加量18 mL、花生汁添加量18 mL、银杏汁添加量8 m L、白砂糖添加量6%,并添加0.1%的柠檬酸及2%的CMC-Na作为稳定剂,此时所制备的复合饮料呈均匀乳白色,富有荸荠、银杏和花生特有的自然清香风味,酸甜适中,口感良好,稳定性良好。产品含有4.62%的蛋白质和2.21%的脂肪,固形物含量为15.32%,符合国家对植物蛋白饮料的规定。     

果浆酶SEB MASH的酶解工艺及其应用研究

研究了印度Advance enzyme公司果浆酶(SEB MASH)应用于苹果浆的酶解工艺条件,对比分析了酶解前后苹果浆各项指标的变化情况。利用L1(645)正交试验,得到果浆酶SEB MASH的最佳酶解条件为:果浆酶用量0.015 g/100 g苹果浆、酶解时间30 min,酶解温度35℃,在此条件下苹果浆的出汁率为95.39%;酶解后苹果的出汁率比直接榨汁的出汁率(75.36%)提高了26.58%。酶解前后的对比分析结果表明,果浆酶SEB MASH有效地提高了苹果榨汁的出汁率,果胶含量以及果渣质量比酶解前分别降低了55.09%和67.6%,且果浆酶处理后果汁的透光率和色值均有较大提高。所以,果浆酶SEB MASH可有效用于苹果果浆,提高苹果加工的出汁率和生产能力。     

复合酶解法浸提红枣汁工艺研究

确定红枣汁制备的最佳生产工艺,在单因素试验的基础上,采用正交试验得出最佳的红枣汁浸提条件为复合酶添加量0.35‰,酶解时间3.5 h,料液比1∶3(g∶m L),酶解温度50℃;此工艺条件下,红枣汁提取率为67.94%。     

复合酶法提取青梅汁的工艺研究

以普宁青梅为原料,以获取率高出汁率为目标,采用正交试验方法研究果胶酶和纤维素酶的用量、酶解时间、酶解温度。结果表明,青梅汁的最佳酶解工艺条件为果胶酶用量2.00 U/kg,纤维素酶用量0.50 U/kg,酶解时间3.0 h,酶解温度30℃,出汁率为76.14%。。     

一种莲藕复合果蔬饮料的工艺研究

对莲藕汁饮料的生产工艺进行研究,将莲藕经过清洗、去杂、切片、护色、打浆和糊化后,添加淀粉酶酶解淀粉后得到莲藕汁,添加白砂糖、苹果浓缩汁、梨浓缩汁、哈密瓜浓缩汁、黄原胶复配,经过均质、脱气、超高温瞬时杀菌和无菌灌装后,制备出莲藕汁饮料。通过单因素试验与正交试验确定了淀粉酶的种类和莲藕汁的酶解工艺,得到α-淀粉酶的最优酶解条件为α-淀粉酶添加量10 U/g,酶作用pH值6.0,酶处理温度75℃,酶解时间50 min;确定了莲藕汁复合饮料的最优配方为莲藕汁添加量70%,白砂糖添加量3%,梨浓缩汁添加量2%,苹果浓缩汁添加量2%,哈密瓜浓缩汁添加量2%。     

酶法制取桑葚汁的工艺研究

测定了桑葚中果胶含量,测定结果为0.36%;利用正交试验确定制汁过程中的用酶量、pH值、温度和时间4个工艺参数的最佳水平。结果表明,最佳的工艺参数为用酶量0.04%,pH值3.5,温度45℃,时间3 h。利用最佳工艺参数制取桑葚汁,使出汁率提高17.2%。     

海带多糖酶解辅助提取工艺的响应面优化及其稳定性研究

对海带加工下脚料中多糖的酶解提取工艺和化学稳定性进行研究。在单因素试验基础上,采用响应面法对酶解辅助提取的工艺参数进行优化,得出4种酶解因素对海带加工下脚料中多糖提取量影响顺序依次为：复合酶添加量＞pH ＞酶解时间＞温度。最优工艺条件为：液料比40∶1（mL/g）,酶解时间135 min,酶解温度55 ℃,酶解液pH 6.0,复合酶添加量2.0%。在该条件下,制得的海带多糖提取量为149.662 g/kg。化学稳定性试验表明,海带多糖提取物在高温和酸性环境下,具有良好的化学稳定性,对碱性环境稳定性较差,是一种化学稳定性较好的天然活性多糖。     

冷冻干燥速溶蛋花汤的加工技术

介绍了运用冷冻干燥技术进行速溶蛋花汤的加工,研究了生产工艺、特点以及影响产品质量的主要因素。试验表明,采用冷冻干燥技术加工的速溶蛋花汤,具有营养丰富、风味独特、方便快捷等特点。     

Measuring of Quantity of Matter-mass and the Measuring of Inertia of Matter-momentclm

A new definition of inertia,i.e. the momentum is the measuring of inertia of matter, is proposed. The article through and etc., subjects, the correctness of the new notion of inertia:The monentum is the measuring of inertia has been demonstrated, and the unsolved contradictions of the traditional definition of inetia. And the mass is the measuring of inertia has been revealed.     

壳聚糖对石榴果汁澄清效果的影响

利用壳聚糖的絮凝作用对壳聚糖在甜石榴汁澄清中的应用效果进行了研究,试验结果表明,壳聚糖用量为0.3g/L、澄清时间为60min、温度为35℃时,甜石榴汁透光率可达85%以上,且通过对壳聚糖处理前后可溶性固形物、总酸、VC等营养成分含量的比较,确定以上工艺参数为甜石榴汁澄清的最佳选择。     

香蕉遗传转化方法研究进展

香蕉是热带亚热带发展中国家重要的粮食作物和碳水化合物来源。但近年来,香蕉生产受到严重的病虫危害。大多数香蕉栽培品种是三倍体,生长周期长,而且不孕。由于没有种子,给繁殖和育种带来一定的困难。遗传转化技术的发展为香蕉品种的改良提供了一种有效的手段。香蕉的遗传转化方法有电激法、基因枪法、农杆菌介导法等。农杆菌介导法的应用是香蕉品种改良的一个重大突破。香蕉遗传转化的外植体也发展到多种,有原生质体,胚性细胞悬浮系,分生组织,以及横切薄片等。近几年,随着分子生物学的发展,出现了转化效率更高,重复性更好的香蕉遗传转化技术。如农杆菌和基因枪结合法,离心辅助农杆菌介导法、真空渗透技术等。这些新技术新方法的出现,必将推动香蕉产业高速发展。     

新疆布尔津县土地利用格局特征研究

基于RS与GIS技术,利用景观生态学理论及景观格局指数对布尔津县土地利用现状进行定量分析。结果显示为：（1）布尔津县以草地、林地为主要景观类型,镶嵌着耕地、水域等景观类型。（2）四个分区（即高山区、丘陵区、平原区、荒漠区）的林地资源组成差异明显,耕地、居民、交通及工矿用地集中分布在丘陵区和平原区（3）从各项指数来看,高山区的多样性指数较低;平原区是受人文因素最多的区域,景观优势度低,各种土地利用类型比例差异不大,有利于生态可持续发展,但要合理的开发利用;荒漠区生态环境相对脆弱,要加强生态环境的保护与改善。通过该研究对布尔津县的土地利用现状作一个了解,为该县乃至整个地区的景观规划和可持续发展战略提供科学依据。     

酸枣幼根原生质体的制备

以生长6～9 d的酸枣种子幼根为试验材料,0.7 mol·L-1甘露醇作为渗透压稳定剂、pH值5.5～6.0、28℃恒温水浴条件下,以光学显微镜观察的水解总时间、初始产生原生质体的时间、原生质体产量及细胞碎片量为指标,研究通过酶水解来制备酸枣幼根原生质体的方法.结果表明,在含1％果胶酶+4％纤维素酶R-10+3％纤维素...     

影响核桃贮藏品质因素的分析

介绍了几种核桃贮藏方法,综述了影响核桃贮藏品质的几个主要因素,以及针对上述影响因素提出若干解决对策.     

Efficiency of water use of early plantings of sunflower

Rain fed crop production in Mediterranean environments depends to a large extent on strategies that avoid the intense summer drought. Early plantings of sunflower have given consistently higher yields in such environments, but the basis for such yield increases has not been explored. We conducted two field experiments at Cordoba (Spain) to investigate the effects of an early and a late planting date on the components of water-limited crop productivity; namely, water use (T), water use efficiency (TE) and harvest index (HI) of sunflower. The results were generalized by simulating rain fed sunflower yields, under early (1 January) and late (15 March) plantings, for a 25-year period with the aid of a simulation model of the Ceres type (OILCROP-SUN) which has been validated in Cordoba. Experimental seed yields of early plantings in 1989 and 1996 were 2.0 and 3.0 t ha⁻¹, while late plantings yields were 1.3 and 2.4 t ha⁻¹, for the 2 years. Average simulated yields were 2.7 ± 1.1 and 1.9 ± 0.7 t ha⁻¹ for early and late plantings, respectively. For the 2 years, T of early plantings was higher than that of late plantings, but the response of TE and HI to planting date was not the same in the two experiments. In the simulation exercise, T and TE of early plantings were consistently higher than those of late plantings, while there were no differences in the HI for the two planting dates. We conclude that early plantings of sunflower increase rain fed yields by increasing both T and TE, while the impact of planting date on HI very much depends on the crop water stress pattern, which is quite variable from year to year even in the predictable Mediterranean environment.     

Establishment of High-frequency Regeneration System of Explants of Alfalfa

The cotyledon and hypocotyl of eight varieties of alfalfa( Medicago sativa L. )are used to study the effect of different cultivation procedures and genotypes on embryogenic callus and embryoid induction,plant development and transplant of alfalfa.The varieties of alfalfa with high embryoid induction rate and high differentiation rate are screened. A high frequency regeneration system for alfalfa tissue culture is established:which is benifical to the gene transformation of alfalfa.     

Laboratorial Method of Determining Limit of Yielding of Material

Based on the relation between the incipient yield pressure and the limit of yielding in cylinder according to the elastic disabled rule, a laboratorial method of determining limit of yielding of material is designed and a set of experimental data were gained by the method. The incipient yield pressure of the cylinder is gained by analyzing the experimental data, and then the limit of yielding is gained. The laboratorial method has a good reliability as the experimental value has a little error to the theory value. It has a definite engineering signification and theory value to research the mechanical capability of material and the disabled rule of high pressure vessel.