单效降膜式蒸发器在液态奶生产中的设计研究

液态奶生产中的单效降膜式蒸发器浓缩比比较小,蒸发温度不得过高,浓缩后的奶液浓度要求严格不得有较大的波动,因此其蒸发参数要求必须稳定,无论是自动控制还是手动控制其进料质量分数、进汽压力必须稳定,这样才能获得良好的使用效果。     

茶多酚超低温浓缩设备研究

茶多酚在食品、医药、日化、轻化、保健等方面有诸多应用,市场需求量巨大,但茶多酚组成复杂,各有效成分对温度比较敏感,沿用传统的设备进行浓缩影响了茶多酚纯度、品质和得率,限制了其应用范围。茶多酚超低温浓缩设备采用自动推进式刮板薄膜成形技术和低负压蒸发技术,实现了超低温加热、超低温蒸发,降低蒸发温度,增加蒸发效果,使茶多酚活性成分在浓缩过程中免受高温破坏,保证了终端产品的品质。     

2010年国内外蜂胶研究概况（二）

2．4蜂胶提取浓缩技术的研究 蜂胶化学成分复杂，毛蜂胶不能直接食用，必须用溶剂提纯其中的活性成分，而提纯所有的溶剂必须浓缩去除。蜂胶浓缩方法主要有水蒸气蒸馏和冷冻干燥法。采用水蒸气蒸馏的方法，蜂胶中对热敏感的化合物以及一些分子量低的化合物可能会随溶剂蒸发而损失。采用冷冻干燥的方法，耗能高，而且温度也需要70℃。     

LiOH·H_2O中除F~-、SO_4~(2-)工艺探索进展

介绍氢氧化锂溶液中除F-、SO42-方法的摸索性实验及其实验结果,确定重结晶法去除F-、SO42-的工艺方法并经过生产性重结晶验证试验。试验表明,氢氧化锂溶液采用间断定量蒸发操作及确立的工艺控制参数:原溶蒸发浓缩约比为1:0.3;蒸汽压力0.10MPa~0.15MPa;蒸发锅内真空度为-0.065MPa;蒸发时间在2.0h~2.5h;冷却水快速冷却至浓缩液温度45℃~55℃;使用三足式离心机制备的单水氢氧化锂中F-、SO42-含量符合指标要求,其杂质元素F-100μg·g-1、SO42-30μg·g-1,一次直收率为60%左右。     

蒸发浓缩工艺在婴幼儿配方乳粉加工中的应用

婴幼儿配方乳粉生产加工中最重要的步骤之一是将液态原料乳中的水分最大限度地除去,但在除水过程中,原料乳中所含各种营养成分的物理结构和外观均会发生很大的变化,因此采用何种脱水工艺对终产品的感官接受度、营养成分保留度具有决定性的影响。用蒸发浓缩工艺生产婴幼儿配方乳粉是在真空状态下,低温蒸发,以脱去原料乳中将近50%的水分,且能最大限度地保留其中的营养成分。本文从蒸发浓缩工艺的原理、流程、注意事项等方面进行论述,为乳品企业提供参考     

蜂产品食品加工文献专利介绍

一、固体蜂蜜蜂蜜经脱水过程制成固体蜂蜜是在真空蒸发器中进行的。为保持蜂蜜成分,要求脱水温度为40—60℃,持续在一小时以内。脱水后,可在20℃左右的温度下加压成型,制成片状、粒状或矩形状等固体蜂蜜。据讯,用此法加工的固体蜂蜜,糖化酶的活性保持不变。《英国专利1378104》二、粉末蜂蜜日本提出一种制作粉末蜂蜜的方法,过程是将蜂蜜放在容器中加热——脱水——浓缩——粉碎。蒸发设备是采用带条板式搅拌器的套层蒸发锅或机械搅拌型的薄膜蒸发装置;蒸发温度低于100℃、     

氯化胆碱浓缩工艺改进

氯化胆碱作为一种饲料添加剂在国内生产历史不长，生产技术水平与日益增长的市场需求很不相称。本文对改进其浓缩过程工艺作一探讨。1氯化胆碱水溶液的蒸发特性氯化胆碱水溶液的蒸发特性基本上服从拉乌尔律，即溶液的沸点随氯化胆碱含量的增加而升高。在低浓度时，沸点随含量增加上升的幅度不大，高浓度时沸点上升得非常迅猛。作者作了测试结果列于下表。从表中可以看出，含量在60％以下时，沸点随含量上升的比较缓慢，在一般条件下较容易浓缩，当含量提高到60％以上时，沸点骤然上升，浓缩越来越困难，当其含量高达75％以上时，再提高浓度…     

味精母液生产蛋白饲料开发前景见俏

我国年产味精40多万t，每年在生产中排放的干固物达七八十万t，不仅污染了环境，还造成大量资源的浪费。以味精等电母液为处理对象，将其蒸发浓缩处理并从母液中2次提取谷氨酸和硫酸铵，最后再将浓缩母液固体发酵生产活性蛋白饲料，实现无废弃物排放，达到清洁生产。     

鲜奶浓缩操作易发生的事故及原因

鲜奶浓缩,就是用加热的方法,将牛奶中的一部分水汽化,使牛奶中的干物质含量提高。我们生产奶粉是在减压下进行蒸发,使牛奶的沸点降低,称为真空浓缩。这种工艺,牛奶的营养成份损失很小,并有利于产品的色泽、风味、溶解度。同时,由于牛奶浓缩在密闭的容器内进行,避免了外界污染,从而保证了产品的质量。     

高效液相色谱法测定鸡蛋中的三聚氰胺

实验用高效液相色谱法测定鸡蛋中的三聚氰胺.鸡蛋样品经酸性缓冲液提取,混合阳离子固相萃取柱净化,提取物蒸发浓缩至干,流动相溶解,过滤用HPLC 进行分析.结果表明,此方法鸡蛋中三聚氰胺检测限为0.5 mg/kg,空白样品的加标回收率为92 %～103.5 %,能满足鸡蛋中三聚氰胺残留量检测的技术要求.     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.     

Mechanism of Action of Probiotic Function of Lactobacilli

乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制.     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …