磺甲基化聚丙烯酰胺降失水性能的研究

采用磺甲基化反应对聚丙烯酰胺进行了改性。探讨了反应条件对产物性能的影响。实验证明:磺甲基化聚丙烯酰胺的抗盐性和水溶性均得到改善,可用作油井水泥降失水剂。     

Identification of copy–paste regions in digital image

In recent technocrat world, an alteration of a digital image is more ubiquitous amongst techno‐savvy professionals, which has also been proved recurrent even for laymen. This has been popularized on account of a lucid access of different types of image‐editing software. Copying a particular region from a digital image to selective location within the same image is one of the good citations of image doctoring. Usually, the bitmap pictures are represented in the form of three‐channel color image, in which the algorithm identifies the similar areas with an assumption of image acquisition in 24 bits Bitmap format. In the present article, an exclusive procedure was applied to produce an output image, pinpointing the copy–paste area with more than 90% accuracy. The resultant image was depicting a forgery operation presumed to be performed, which determined two areas of similarity. A novel approach of 1‐connected graph was applied, as the forgery is not believed to be done in the form of a petite point‐like area. Finally, the forgery area was exposed with an aid of discerning color value, commonly as a black color for an apparent visibility of an image. The present application will be a tool in image forensics that can be applicable to identify the copy–paste regions in a single bitmap image. This article refers to a new approach for detecting the image portions which are copied from another image. Besides, the present investigation discusses an algorithm effectively implemented to determine the areas formed by copy–paste operation in an image. © 2010 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 20, 367–369, 2010     

酶法制酱

酶法制豆酱、面酱工艺，利用蛋白酶及淀粉酶分解原料中的蛋白质及淀粉，能减少制曲工序，节约能源及设备，稳定产品质量。该文对酶法制酱的生产工序、设备、产品质量与传统曲法制酱进行了比较，并对产品应用加以建议。     

酱醅色的剖析

在制酱过程中，酱的颜色是由酱醅色转变而来的，酱醅色又与酱醅成熟度有着一致性及同步发展转换关系。当酱醅颜色为红黄色或棕红色时，也正是酱醅的最佳成熟状态。应及时调控与保持酱醅稳定的状态，防止过熟而造成酱中营养物质的损耗。     

淀粉替代剂在双胶纸中的应用

探讨了淀粉替代剂部分替代淀粉进行表面施胶,使双胶纸质量有一定提高,并降低了生产成本。实验表明,当淀粉替代剂替代比例为20%时,方案最佳,吨纸成本可节约22.09元,胶液成膜性比未使用替代剂要好,而且成纸的表面强度和裂断长分别比未使用替代剂时提高21%（正面）/17%（反面）和24%,透气度也有所降低,平滑度与之前相当,表面施胶剂烷基烯酮二聚体（AKD）的用量比未使用替代剂时节约3.1 kg/t（纸）。     

超微粉碎牦牛骨泥经发酵和酶解后游离钙和氨基酸态氮的变化

用保加利亚乳酸杆菌发酵和用胰蛋白酶、中性蛋白酶、木瓜蛋白酶酶解超微粉碎牦牛骨泥,测定骨泥巾的游离钙（Ca^2＋）、氨基酸态氮含量和pH值的变化。结果表明,经保加利亚乳酸杆菌发酵36h后,骨泥中游离钙的含量从12．3mg／100g增加到2145．3mg／100g,而氨基酸态氮的含量从117．7mg／100g增加到233．4mg／100g;经胰蛋白酶、中性蛋白酶和木瓜蛋白酶分别酶解4h后,游离钙的含量从233mg／100g分别增加到893mg／100g,623mg／100g和523mg／100g,氨基酸态氮则从1065mg／100g分别增加到134．5mg／100g、149．4mg／100g和154．1mg／100g。通过比较显示,利用乳酸菌发酵处理骨泥后,游离钙含量是酶解处理骨泥的24倍,氨基酸态氮含量则为酶解处理的1．5倍。因此发酵比酶解处理能得到更多的游离钙和氨基酸态氮。     

日本酱的种类及工艺技术与中国酱的比较

最早发源于中国的日本酱经过长期发展,已逐渐演变成日本特有的产品。日本酱主要有米酱、麦酱、豆酱,从原料处理到发酵熟成都与质量特征紧密相连,制曲及其投料等决定着产品的感官特色,形成了若干与中国酱品在工艺上的重要不同;日式酱的分类取决于制曲时所用的原料种类;日式豆酱主要是以酶解方式生产的。     

响应面分析法优化HS-SPME 萃取黄豆酱挥发性成分工艺研究

为了优化黄豆酱挥发性风味成分检测的SPME 萃取效率,采用Plackett-Burman 设计法和响应面分析法对黄豆酱风味萃取条件进行优化。先用Plackett-Burman 设计从8 种萃取因素中筛选出对总峰面积有显著影响的因素,再用最陡爬坡试验及Box-Behnken 设计进一步优化。结果表明,萃取温度、萃取时间和基体中的无机盐添加量是影响总峰面积的显著因素,优化后的萃取条件为萃取温度56℃、萃取时间42min、基体中的无机盐添加量0.98g。在优化条件下,与初始最大总峰面积12880000 相比,总峰面积提高到13107129。     

Bacterial community succession and biogenic amine changes during fermentation of fish-chili paste inoculated with different commercial starter cultures

The microbial dynamics, diversity and succession characterisation during the fermentation of fish-chili paste, with and without starter cultures by high-throughput sequencing, were investigated to identify the relationship between microbial composition and the accumulation of biogenic amines. Results showed that Firmicutes was the predominant phylum, and Lactobacillus and Weissella were the main genera during fermentation process, regardless of the inclusion of starter cultures. Compared with naturally fermented samples (NS; no starter cultures), Pediococcus and Staphylococcus flourished in samples inoculated with SBM-52 starter culture (Staphylococcus xylosus + Staphylococcus carnosus + Pediococcus pentosaceus + Pediococcus acidilactici). Staphylococcus also accounted for a larger proportion in samples inoculated with WBX-43 starter culture (Staphylococcus xylosus + Staphylococcus carnosus). Furthermore, Enterobacter was inhibited in inoculated samples. Unweighted pair-group method with arithmetic means and principal component analyses revealed that microbiota structures were different among NS, SBM and WBX samples. In case of biogenic amines, the concentration of putrescine, cadaverine and tyramine increased to higher levels in NS samples compared with inoculated samples. Our work also investigated the relationship between core bacterial communities and biogenic amines. This study provided an improved understanding for the effects of starter cultures on the microbial community and the quality of fish-chili paste.     

超高效液相色谱-串联质谱法同时测定番茄酱中18种真菌毒素

目的建立同时检测番茄酱中18种真菌毒素的超高效液相色谱-串联质谱(ultra performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)分析方法。方法样品经80%乙腈溶液提取后,通过自制固相萃取柱排除杂质干扰,流出液经氮吹至近干后,采用Acquity CORTECS UPLC C_(18)色谱柱分离,用1mmol/L乙酸铵-甲醇作为流动相进行梯度洗脱,电喷雾正负离子模式电离,多反应监测模式检测,基质校准外标法定量。结果 18种毒素在各自浓度范围内呈现良好线性关系(r~20.99);在3个不同添加水平下的平均加标回收率均在77.1%~105.4%之间,相对标准偏差为0.48%~6.98%。利用本实验建立的方法对40份番茄酱样品进行检测,共有35份番茄酱样品呈阳性,检出6种真菌毒素。结论该方法灵敏度高,操作简单,快速可靠,重复性好,可满足对番茄酱中18种真菌毒素检测的要求。