膜分离技术在番茄汁浓缩工艺中的应用   总被引：2，自引：0，他引：2  

高辉  安兴才  祝霞  盛文军  张鹏  王文正 《甘肃农业大学学报》2007,42(1):123-126

膜分离技术由于具有结构简单、操作容易、无需加热、能耗低、速度快等特点,使其正广泛地应用于食品工业领域.介绍了膜分离原理及特点,并对管式反渗透、离心分离与卷式反渗透、陶瓷微滤与卷式反渗透、直接渗透浓缩四种类型的膜分离技术的优缺点及其在番茄酱加工工艺中的应用和发展方向作了概述,以期为改进膜分离技术在番茄汁浓缩工艺中的应用找到新的途径.  相似文献   

Toxoplasma gondii in Switzerland: a serosurvey based on meat juice analysis of slaughtered pigs, wild boar, sheep and cattle     

Berger-Schoch AE  Bernet D  Doherr MG  Gottstein B  Frey CF 《Zoonoses and public health》2011,58(7):472-478

Toxoplasmosis is one of the most important zoonotic diseases worldwide and is caused by the protozoan Toxoplasma gondii. Besides vertical infection during pregnancy, humans can get infected post-natally either by peroral uptake of sporulated Toxoplasma oocysts or by ingestion of tissue cysts upon consumption of raw or undercooked meat. The aim of this study was to approximate the risk of human infection via meat consumption by estimating the seroprevalence of T. gondii in slaughtered animals in Switzerland and to compare data with prevalences assessed 10 years ago. The study included pigs, cattle, sheep and wild boar of different age groups and housing conditions whenever possible and applicable. A P-30-ELISA was used to detect T. gondii-specific antibodies and to determine seroprevalences in meat juice of slaughtered animals. A total of 270 domestic pigs (120 adults, 50 finishing, 100 free-ranging animals), 150 wild boars, 250 sheep (150 adults, 100 lambs) and 406 cattle (47 calves, 129 heifers, 100 bulls, 130 adult cows) were tested. Seropositivity increased with the age of the assessed animals. Independent of the age-group, the overall seroprevalence was lowest in wild boars (6.7%), followed by pigs (23.3%), cattle (45.6%) and sheep (61.6%), respectively. Conventional fattening pigs and free-ranging pigs surprisingly had comparable seroprevalences (14.0% and 13.0%, respectively). Unlike in other European countries, where generally a decrease in the number of seropositive animals had been observed, we found that the prevalence of seropositive animals, when compared with that of 10 years ago, had increased for most species/age groups. Conclusively, the results demonstrated a high seroprevalence of T. gondii in animals slaughtered for meat production and revealed that increasing age of the animals is a more important risk factor than housing conditions in Switzerland.  相似文献   

响应面法优化枳椇果汁的制备工艺     

王维彦  兰光  马力  张存莉 《北方园艺》2011,(20):156-159

以枳犋果柄为原料,通过单因素试验和响应面法,优化工艺条件,探讨枳椇果汁的生产工艺.结果表明:枳犋果汁提取的最佳工艺参数为水浴温度50℃、液固比10∶1、pH值2.5、浸提时间4h、果胶酶0.045 g/10g干果.以此工艺制备的枳椇果汁具有枳犋特有的果香,风味独特,味道酸甜可口.  相似文献   

固定化酵母粒子强化及其对甜高粱茎秆汁液乙醇发酵的影响     

沈飞  刘荣厚 《农业工程学报》2007,23(5):180-184

采用正交试验设计开展了三亚乙基四胺(TTA)和戊二醛(GLU)的浓度和处理时间对海藻酸钙固定化酵母粒子的化学强度影响的试验研究，并以甜高粱茎秆汁液为原料，在5 L的反应器中进行乙醇发酵试验，考察强化后的固定化酵母粒子对乙醇发酵的影响。结果表明，最优的固定酵母粒子强化处理的方案为：TTA浓度为0.5%，处理时间为120 min；GLU浓度为0.5%，处理时间为8 min。连续8批次的甜高粱茎秆汁液乙醇发酵试验结果表明，最优组合强化后固定化酵母粒子用于乙醇发酵时，平均乙醇得率和变异系数(CV%)分别为84.78%和8.08%，而未强化的固定化酵母籽子为84.32%和9.68%，可见，最优组合强化后的固定化酵母粒子的发酵性能略优于未强化的固定化酵母籽子。该文为固定化酵母发酵甜高粱茎秆汁液制取生物乙醇技术的研究提供了参考。  相似文献   

玉米茎秆汁液对土壤的减水减沙效益及其机理     

魏霞  苏辉东  李勋贵  叶永铸  彭海鑫  黄青能  何志文 《农业工程学报》2015,31(21):142-147

为研究土壤改良剂玉米茎秆汁液对中国西部地区水土流失的影响和机理,该文通过室内土壤理化性质测定和人工模拟降雨试验,研究了地表施加玉米茎秆汁液对土壤团聚体的平均重量直径、土壤有机质质量分数和土壤减水减沙效益的影响。试验以未施加任何玉米茎秆汁液的黄土坡面为对照,设计单位面积玉米茎秆汁液施加量1 041.7 mL/m2,施加汁液体积分数25%和50%,降雨强度为50 mm/h,研究玉米茎秆汁液施加对土壤减水减沙的影响。结果表明,玉米茎秆汁液的施加可以增加土壤有机质的含量,提高土壤团聚体的平均重量直径,降低产流产沙速率。对照、体积分数25%和50%汁液施加下的土壤团聚体平均重量直径分别为0.18、0.46和0.51 mm,土壤有机质质量分数分别为5.70%、6.75%和7.17%。较对照,体积分数25%和50%汁液施加下,土壤的减水效益分别为45.81%和48.34%,减沙效益分别为65.00%和75.47%。玉米茎秆汁液的减水减沙效益随时间的推移而降低,月均减水、减沙效益降低量约为1.25%和1.41%,研究中施加体积分数25%和50%汁液的土壤减水减沙效益约可持续3和4.5 a。综上,玉米茎秆汁液作为土壤改良剂在施加量为1 041.7 mL/m2时,茎秆汁液与水的体积比为1:1时,效果较好。该研究可以为将玉米茎秆汁液作为土壤改良剂用于土壤侵蚀的防治提供施放参考。  相似文献   

Soil classification system in the world and application to agriculture and forestry. 7. Application and development of soil classification     

Makoto NAKAI 《Soil Science and Plant Nutrition》2006,52(1):137-137

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枣的耐藏性及其生物学特性研究   总被引：15，自引：0，他引：15  

任小林  常经武 《园艺学报》1995,22(1):25-28

对１４个枣的鲜食、制蜜品种的耐藏性进行了比较研究，结果表明：早熟脆枣，灵宝圆枣、油福水枣、合阳玲玲枣比较耐藏；枣果实耐藏性与呼吸速率呈显著负相关，与失水速率呈显著正相关。果实呼吸速率，失水速率、果肉细胞大小和果肉比重是影响耐藏性的主要因子。  相似文献   

包衣尿素在春白菜上的应用效果研究     

谷佳林  曹兵  徐秋明  边秀举  李亚星  张琳  杨宜斌 《勤云标准版测试》2006,(4)

以枣优良品种骏枣为试材,研究了多种因素对其离体叶片及大田幼嫩茎段再生效率的影响。结果表明,幼嫩茎段再生较容易。叶片再生与生长调节物质种类和浓度及叶片成熟度有关。枣叶片不定芽再生的最佳培养基为1/2MS(大量元素减半) TDZ0.5mg/L IBA0.2mg/L。不定芽再生率以上部叶片最高。  相似文献   

秋季叶施尿素及乙烯利对枣树贮藏氮素的影响   总被引：11，自引：1，他引：10  

赤中宁  曾骧 《园艺学报》1991,18(2):102-106

枣树(Zizyphus jujuba Mill.)秋季叶施尿素、乙烯利及尿素十乙烯利均可促进叶片及落性枝的氮素向树体回流,增加树体贮藏氮素水平,尤以尿素 200ppm乙烯利的效果最佳;尿素及乙烯利处理均增加了次年枣吊长度、平均单果重及枣果还原糖含量;尿素处理还显著增加了叶片及新梢含氮量,座果数,但降低了枣果蔗糖含量。枣树秋冬季地上部与根系具有同等重要的贮藏氮素作用;蛋白态氮是主要贮藏形态,为非蛋白态氮的2—3倍。  相似文献   

Changes in ripening behavior of ‘d'Anjou’ pears (Pyrus communis L.) after cold storage     

P.M. Chen  W.M. Mellenthin  D.M. Borgic 《Scientia Horticulturae》1983,21(2):137-146

‘d'Anjou’ pear fruit, harvested at optimum maturity with flesh firmness of 6.8 kg, were stored at ?1.1°C. Fruit were ripened at 20°C for 15 days following storage for 1–8 months. Dessert qualities were evaluated organoleptically on Day 10 of each ripening period. Changes in fruit firmness, extractable juice, titratable acids, solubl solids, respiration, ethylene production and internal ethylene were determined daily during each ripening period. Fruit firmness declined continually from 6.8 kg at harvest to 4.5 kg after 8 months of storage. Fruit stored for 2–8 months softened with a similar pattern during a 15-day ripening period at 20°C, while fruit stored for 1 month softened at a slower rate during ripening to 3.2 kg, with a coarse and dry texture after 15 days at 20°C. Fruit stored for 2–4 months ripened with the desirable buttery and juicy texture, while those stored for more than 5 months ripened with a coarse or mealy and dry texture. The buttery and juicy texture was highly correlated with a lower extractable juice, which could be used for quantitative determination of storage life based on ripened fruit quality. Changes in titratable acids and soluble solids during each ripening period were not associated with changes in dessert qualities of the ripened pears. Rates of respiration, ethylene production and internal ethylene during ripening at 20°C varied with duration of storage, but were not associated with changes in dessert qualities of the ripened fruit.  相似文献