干红枣去皮方法研究

以干红枣为原料,采用碱液、蒸制和煮制等方法研究干红枣的去皮工艺。结果表明,干红枣的最佳复水条件为时间6 h,温度60℃。碱液去皮的最佳条件为:质量分数5%,时间60 s;蒸制25 min或煮制16 min,去皮效果也较好。     

枣树小冠疏层形空间产量分布及果实品质比较

为了探究枣树小冠疏层形的结构特点、各冠层产量分布及果实品质状况,为枣树造形提供理论支撑,以‘鲁枣2号’枣为试材,研究枣树小冠疏层形的个体结构、生长特性、产量分布及果实品质差异。结果表明：小冠疏层形中间冠层为产量主要分布层,枣果数与枣吊数最多,但是果枝比较其他2个冠层要低,下层平均单果重最大,上层叶绿素SPAD值、叶面积、枣吊长度和果实可溶性固形物含量均比下层高。因此,在对枣树小冠疏层形进行整形修剪时,要严格控制树冠上层的营养生长,适当控制中间冠层侧枝长度,缩放下部冠层侧枝,这样有利于提高果实的品质和产量。     

紫外线处理对鲜切菜品质的影响

以豇豆为材料,探索紫外线处理对鲜切菜品质的影响,并为我国鲜切蔬菜的保鲜技术提供参考依据。实验用紫外线照射鲜切菜不同时间(0,20,30,40,50,60min),并测定细菌、乳酸菌、大肠杆菌、真菌的菌落总数,以及亚硝酸盐含量、VC含量和失质量率。结果表明,照射时间为30min,可有效控制鲜切豇豆中微生物的生长和繁殖,并能有效杀灭(甚至彻底清除)大肠杆菌,对真菌、乳酸菌、肠杆菌也有明显的抑制作用;鲜切菜中亚硝酸盐含量最低,VC含量与其他处理相比保存最好,感官品质良好。     

鲜榨果汁抗氧化性能的比较

测定了14种鲜榨果汁中黄酮和VC的含量,通过果汁对羟自由基、超氧阴离子自由基和过氧化氢的清除试验,比较了其抗氧化性能的强弱。结果表明,抗氧化性由高到低顺序依次为猕猴桃、草莓、橘子、木瓜、橙子、柠檬、苹果、蜜柚、杨桃、梨、枇杷、芭乐、西瓜、菠萝。鲜榨果汁中黄酮含量与其抗氧化性之间有显著的相关性。说明鲜榨果汁的抗氧化性能主要是由含有的黄酮类化合物决定的。     

JMF-3A型麦芽辊式破碎机的研制

为了满足小型啤酒坊、酒店及家庭对自酿鲜啤酒的生产需要,研制了一种与小型啤酒生产线配套使用的麦芽辊式破碎机。通过solidworks建模运动仿真和生产试验证明,该机生产效率高,破碎效果好,结构紧凑,运转平稳,安全性好且整机振动小,噪音低。满足了市场需求,提高了经济和社会效益。     

红枣气体射流冲击干燥收缩特性研究

Chinese jujube originated in China and has a long historical standing. China is the only country which can produce a great amount of Chinese jujube in the world. Modern research showed that the nutrition of Chinese jujube is abundant. Chinese jujube has great medicinal and food value, with high economic value and good prospects for development. Shrinkage characteristics of dates generally refer to volume shrinkage characteristics of whole dates. Large fruit and plump grain appearance of dates is the first choice of consumers to buy elements. The volume of dried jujube points to the consumer’s heart, and is an important indicator of consumers whether to buy. Jujube processing enterprises grade the date in accordance with its size, different grades dates have different value and price. Therefore, drying is the most important steps during the dates processing as it affects directly the quality of the product, and the shrinkage characteristics is the most important quality characteristic of Chinese jujube after drying. However, the traditional natural desiccation and desiccation in the drying room of the red dates has many problems. The conventional drying method for Chinese jujube has some disadvantages of severe shrinkage, long drying time and large energy consumption etc. Therefore, in order to improve the quality of dried Chinese jujube and reduce the shrinkage, it is imperative to replace the traditional drying method with the modern technologies. Air impingement drying technology was applied to dry Chinese jujube. The drying characteristics of shrinkage, moisture effective diffusivity considering shrinkage characteristics and the activation energy of Chinese jujube shrinkage were investigated under different air temperatures (55, 60, 65 and 70℃) and air velocities (6, 9, 12 and 15m/s). The dynamic changes of the regular pattern for the shrinkage characteristic of Chinese jujube in the air impingement drying process were studied, the results showed that the volume relative shrinkage ratio of Chinese jujube appeared to increase and then decrease with the increase of air temperature and air velocity. Considering shrinkage characteristics, the moisture effective diffusivity of Chinese jujube in the air impingement drying process through the Fick’s second law was obtained. The diffusivity appeared to increase and then decrease with the decrease in moisture content in dry basis of Chinese jujube. The Arrhenius equation calculated the shrinkage activation energy of the Chinese jujube was 1281kJ/mol. This research provided technical basis for shrinkage characteristics of Chinese jujube using air impingement drying technology.     

黄土半干旱区枣林深层土壤水分消耗特征

黄土区人工经济林普遍出现利用性土壤干层,制约着植被的恢复与重建。为了准确计算黄土半干旱区密植高产枣林(Ziziphus jujube Mill.)深层土壤(2 m以下)水分消耗量,采用根钻法(洛阳铲)分层获得从地表到细根分布最大深度范围内的土壤含水率。结果表明:枣林深层土壤水分消耗是一个逐渐加深、逐渐向下的过程。2、4、9和12 a生枣林深层土壤水分消耗量分别为0、29.6、149.9和155.7 mm,可再供水量分别为203.7、167.7、35.5和29.7 mm;枣林生长第9年后,2~4 m土层几乎没有可利用的水分,现有降水和滴灌已经不能满足枣树的耗水需求,枣林吸收土壤水分有向深处延伸的趋势。以降水入渗最大深度为上界、细根分布最大深度为下界计算的深层土壤水分消耗量,能更准确地评估林地利用性土壤干层的程度和深度。     

基于梨枣轻微损伤的可见/近红外光谱判别研究

利用可见/近红外光谱技术对梨枣轻微损伤的分类判别建模方法进行研究。分别采用PLS-LDA(线性)和LS-SVM(非线性)建立判别模型,分析比较不同预处理方式和建模波段对模型精度的影响。结果表明:经9点平滑预处理后的短波近红外(780~1100nm)PLS-LDA模型判别效果最佳,校正集和预测集的正确识别率分别达到97.8%和96.7%。     

基于神经网络红枣红外辐射干燥预测模型建立

针对红枣红外辐射干燥含水率的变化具有非线性和时变性、很难利用现有的模型构造一个数学模型来描述其变化规律的问题,利用Mat Lab神经网络工具箱和红枣红外辐射干燥特性试验数据建立了神经网络预测模型。通过对实测值和模型预测值进行分析研究,得出利用BP神经网络可以较快速、准确地建立模型来描述含水率的变化规律,且模型的预测值与试验测试值误差较小,能很好地实现在线预测的效果。     

不同品种鲜食核桃冷藏期间呼吸强度及品质变化

为探讨鲜食核桃冷藏期间品质变化规律,在(0±1)℃、相对湿度(RH)70%～80%的贮藏条件下,以辽河4号（L4）、西扶1号（X1）和西扶2 号（X2）核桃品种为试材,采用0.03 mm 厚聚乙烯（PE）袋包装,定期对其相关指标进行测定。结果显示,贮藏初期（15 d）呼吸强度迅速下降,之后维持在低且平稳的水平;3个品种之间水分、脂肪、蛋白质及氨基酸含量均呈现极显著差异;贮藏期间蛋白质含量变化不显著;脂肪、不饱和脂肪酸含量及维生素E含量总体呈现下降趋势;氨基酸含量30 d 时最高,之后保持下降趋势;酸价及过氧化值呈现上升趋势;贮藏中后期（60 d后）酸价、过氧化值、好果率及感官品质急剧下降。结果表明：鲜食核桃贮藏品质受品种影响很大,60 d 为鲜食核桃适宜贮藏期,以L4品质最好。