制钉业钉屑分离装置改进

制钉业中锯末与钉屑分离的方法有水洗式、风车式和旋风式,3种方法各有优缺点,都需要解决均匀喂料的问题。分离方式改进采用内吸式百叶窗斜坡分离法,能够将锯末清理干净,钉屑质量好,副产品钉屑和锯末装袋方便,对环境污染小;喂料系统改进采用机械喂料替代人工喂料,并通过分离系统实现锯末和钉屑的均匀分离;物料提升系统由电动葫芦、提升轨道和提升斗3部分组成。钉屑分离装置总投资3万元左右,应用后解决了锯末、钉屑分离的问题。     

含铬革屑脱铬提取胶原蛋白的研究进展

制革含铬革屑的主要成分为胶原蛋白和铬,具有较大的资源化利用价值。国内外对含铬革屑资源化作了大量的工作,提出了氧化法、水解法及结合法等脱铬提取胶原蛋白的技术。为实现含铬革屑资源化,促进制革工业生态化和可持续发展。以含铬革屑脱铬率与胶原蛋白提取率为主要评价指标,简要介绍了各种含铬革屑的资源化技术,分析各种资源化技术的特点与优缺点。提出结合法应为含铬革屑脱铬提取胶原蛋白的最佳方法,并对含铬革屑的资源化利用前景作了展望。     

天然皮革边角料的资源化利用进展

皮边角料/皮屑、革屑是制革过程中的主要固体废弃物之一,其主要成分为胶原蛋白,如何将其资源化利用成为皮革产业可持续发展的问题之一.本文综述了皮革生产过程中产生的生皮屑、灰皮屑、铬鞣革屑、无铬鞣革屑、成品革屑的资源化利用方法并提出了建设性的建议.     

铬革屑制备蛋白填充复鞣剂和铬鞣剂的研究（二）

1．2国内外研究现状铬革屑回收利用方式大致可分为脱铬和不脱铬两大类。铬革屑不脱铬一般回用于制革工业,其方法是将铬革屑用酸水解成适当分子量大小的含铬胶原多肽后直接用于皮革填充。     

红外光谱法研究革屑碱法水解的工艺条件

革屑水解程度的控制是利用革屑制备胶原蛋白涂饰剂的关键步骤之一。介绍了用红外光谱法确定革屑碱法水解工艺条件的方法。探讨了改变 p H值、水解时间、碱的种类等试验条件后 ,水解液红外光谱的特征。     

铬鞣革屑的资源化研究进展

综述了铬鞣革屑利用的方法及发展,重点介绍铬鞣革屑在复鞣、填充、加脂、涂饰等方面的研究应用.     

利用铬鞣革屑的研究进展

综述了铬鞣革屑利用的方法及发展，重点介绍铬鞣革屑在复鞣、填充、加脂、涂饰等方面的研究应用。     

铬鞣革屑的资源化研究进展

综述了铬鞣革屑利用的方法及发展，重点介绍铬鞣革屑在复鞣、填充、加脂、涂饰等方面的研究应用。     

含铬革屑的资源化利用

含有重金属铬的含铬革屑制革废弃物,如果不能有效处理,将会造成环境污染及人类等健康损害。在环境问题日益严重和资源日趋贫乏的今天,对含铬革屑的资源化利用具有巨大的环境和经济价值。本文简述了近年来对含铬革屑的利用方法。     

含铬革屑的资源化利用

含有重金属铬的含铬革屑制革废弃物,如果不能有效处理,将会造成环境污染及人类等健康损害。在环境问题日益严重和资源日趋贫乏的今天,对含铬革屑的资源化利用具有巨大的环境和经济价值。本文简述了近年来对含铬革屑的利用方法。     

小麦面条和面过程面絮特征与检测研究进展

和面作为面条制作的关键性工艺，形成的面絮直接决定面条最终品质，但面絮品质缺少客观检测方法，制约了面条工业化发展。面絮形成是谷物粉体颗粒与水分混合形成团聚体的湿法造粒过程，受到面粉自身组分、水分加入量、和面方式和辅料的影响。面絮的颗粒度较为均匀、水分在面絮内部和面絮之间分布均匀、面筋网络结构充分有效包裹淀粉是良好面絮的共同特征。面絮状态图像深度学习分析把面絮形成分为润湿黏连、聚集成形、破裂分散、稳定平衡4个阶段，稳定平衡阶段在精准判别和面终点中起到至关重要的作用。目前面絮颗粒大小评价以目测、时间控制、感官评价为主，还无法实现仪器精确测定或在线质量检测。通过图像分析，用面絮颗粒图像的阴影面积可以间接反映面絮状态，指导面条工业化生产。本文综述了小麦面条和面过程中面絮的基本特征，分析了面絮形成过程中的水分动态变化、颗粒度变化、面筋网络结构变化及其影响因素，讨论了面絮与面条品质之间的关系，介绍了图像检测方法、其他检测方法在面絮检测中的研究进展。     

采用生物酶法去除山羊绒肤皮屑

尝试采用生物酶法去除山羊绒染色中多年未根本解决的羊绒肤皮点问题。分别选用角质酶、胃蛋白酶和蛋白酶三种生物酶处理了山羊绒肤皮屑,考核去屑效果,研究各生物酶处理的工艺条件,同时考察了处理前后山羊绒损伤情况．结果表明,T.fusca角质酶去除山羊绒肤皮屑工艺条件为：角质酶用量8mL/g,pH=8.0,60℃,5h,浴比1：50,肤皮屑去除率29%．胃蛋白酶去除山羊绒肤皮屑工艺条件为：胃蛋白酶用量6%（o.w.f）,pH=2.2,4℃,6h,浴比1:50,肤皮屑去除率17%．蛋白酶Savinase 16L去除山羊绒肤皮屑工艺条件为：蛋白酶用量1mL/g,pH=8.5,45℃,4h,浴比1:50,肤皮屑去除率46%．在上述工艺条件下,角质酶和胃蛋白酶处理对羊绒有轻微的损伤,可以作为一种新的去除羊绒肤皮点的方法,蛋白酶对羊绒的损伤较严重,不能采用．生物酶法能部分去除山羊绒肤皮屑,有必要进行进一步的研究。     

Comparison of crumb microstructure from pound cakes baked in a microwave or conventional oven

Imaging, light microscopy and scanning electron microscopy were used to compare the microstructure of crumbs from pound cakes baked in a microwave or conventional oven. The microwave baking conditions for pound cake (240 W, 5 min) were established in previous research, conventional baked pound cakes were obtained using a swing oven at 180 °C for 40 min. Statistical differences in total cell, cell/cm² and mean cell area (P?0.05) were observed in the image analysis. Cells from microwaved pound cake crumbs were 20% larger. However, factor shape was 0.81 for both microwave and conventionally baked crumbs, and crumbs from both oven types were similar in appearance. Light microscopy revealed birefringence in crumbs from both types of pound cakes. Scanning electron microscopy revealed that the conventionally baked product had a greater amount of protein matrix however; the matrix structure of the crumb was comparable between microwave-baked and conventionally baked pound cakes. In conclusion, our results suggest that the unique aspects of pound cake dough, including its high content of fat, sugar and moisture, make it well suited to microwave baking.     

基于统计过程控制(SPC)的挂面加工过程质量控制

和面工序是挂面生产的关键环节,充足的和面工序能力是保证挂面产品质量稳定合格的关键。为保证挂面产品质量,以某企业一条挂面生产线为例,对和面过程进行监测,通过控制图法分析和面后面团的质量波动,确定影响质量波动的因素,提出相应的控制方法和控制参数,并对控制效果进行评估。监测的20d,面团水分含量存在1个异常波动点,面团水分均匀度存在1个异常波动点且有连续10个点低于中心线;异常波动的可能原因主要包括湿面头添加较多,和面时间不足,加水量不合适以及加水速度较快。降低波动、提高工序能力的主要方法有：选择品质稳定、适合加工挂面的面粉,选择合适的和面方式和时间,限制干、湿面头的添加量以及规范人员操作。结果表明：统计过程控制(SPC)作为和面工序过程质量控制工具,面团含水量和水分均匀度的波动均明显降低,工序能力均提高到一级,加工质量显著提高。     

Effect of baking method on some characteristics of starch in pound cake crumbs

BACKGROUND: The effect of the baking process (microwave versus conventional oven) on some starch characteristics of pound cake was evaluated. Proximal chemical analysis, total resistant starch (RS), retrograded resistant starch (RS3), differential scanning calorimetry (DSC), and X‐ray diffraction (XRD) were evaluated. Pound cake, one of the major products of Mexico's bread industry, was selected for analysis because the high moisture and fat content in the beaten dough might reduce the quality defects often associated with microwave baking. RESULTS: Crumbs from microwave‐baked pound cakes contained lower moisture than crumbs from conventionally baked pound cake. Lower RS was observed in fresh microwave‐baked than conventionally baked pound cake. RS3 increased significantly in conventionally baked products stored for 8 days at room temperature, whereas slightly lower changes in RS3 were observed in the microwaved product. DSC revealed less gelatinisation in microwaved pound cake which is related to limited water availability during the microwave heating process. The crystallinity peaks present in conventionally baked pound cake might be associated with RS3 content; the resistant retrograded starch formed during storage, is reflected in the XRD pattern. CONCLUSION: Microwave‐baked pound cake crumbs showed less gelatinisation than conventionally baked pound cake crumbs. Copyright © 2007 Society of Chemical Industry     

Production of bread crumbs by infrared-assisted microwave drying

This study is aimed to investigate the possibility of using infrared-assisted microwave drying for production of bread crumbs and to determine drying conditions in halogen lamp-microwave combination oven to produce bread crumbs with the highest quality. Bread crumb dough were dried from about 40.9 to 8% moisture content by conventional, microwave, infrared and infrared-assisted microwave drying separately and in combinations. Halogen lamp and microwave power levels of 30, 50 and 70% were used. Percent reduction in the drying time were 80.2–94.0 for infrared, 96.5–98.6 for microwave and 96.8–98.6 for infrared-assisted microwave drying. ΔE values were lower in microwave drying and higher in infrared drying. Infrared-assisted microwave dried crumbs generally had similar color values with the conventionally dried ones. Effect of power on color change was not observed. All drying methods were found to be effective in increasing water binding capacity, which increased with microwave power in microwave drying but the influence of halogen lamp power was not seen in infrared drying. At fixed microwave (halogen lamp) powers increase of halogen lamp (microwave) power did not affect the water binding capacity in infrared-assisted microwave drying.     

Effect of Baking Conditions on Properties of Starch Isolated from Bread Crumbs: Pasting Properties,Iodine Complexing Ability,and X-ray Patterns

In order to understand starch changes induced by baking process at different locations of a slice of sandwich bread, namely the top, center, and bottom locations, starch was isolated from crumbs baked at two heating rates ( 6.31 and 4.67 °C/min) and evaluated for their pasting properties, gelatinization parameters, and iodine complexing ability. Results showed that starch isolated from the bottom and the center crumbs baked at higher heating rate presented the significant higher final viscosity and higher setback than that isolated from crumbs baked at lower heating rate. Thermal analysis showed that starch isolated from the center crumb of the bread slice presented the lower enthalpy value of gelatinization, confirming that these samples underwent higher heat-moisture treatment during the baking process. After equilibration at 0.97 a_w, the exposure to iodine vapor changed the X-ray diffraction intensity of starch samples. Polarized light microscopy showed that heating affects starch granule morphology due to the higher starch chain mobility and the higher granular swelling when breads were baked at lower heating rate.     

油条风味物质组成分析及添加麦麸对其影响的研究

采用顶空固相微萃取(HS-SPME)和气质联用技术(GC-MS)研究了油条瓤及皮中的挥发性风味化合物,以及添加烘烤麦麸对油条风味物质的影响。结果表明,油条瓤和皮中均含有39种以上风味化合物,油条瓤中以醛类、醇类、酯类为主,油条皮中以醛类、醇类、酯类、酮类、吡嗪类及苯环类为主。油条的主要特征风味化合物为(E,E)-2,4-癸二烯醛、3-甲基丁醛、1-辛烯-3-醇、糠醛和糠醇。烘烤麦麸的添加使得3-甲基丁醛、戊醛、己醛、1-辛烯-3-醇等化合物相对含量增加。     

Bread Staling: Changes During Storage Caused by the Addition of Calcium Salts and Inulin to Wheat Flour

The objective of this work was to study changes in staling parameters of wheat bread formulated with different calcium salts (carbonate, citrate, or lactate) and inulin. The moisture content and texture of crumbs were studied. Moreover, the effect of calcium and inulin levels on crumb firmness during storage was estimated by fitting the Avrami equation. Starch retrogradation and the amylose-lipid complex were evaluated by differential scanning calorimetry (DSC) and X-ray diffraction. Crumbs with high inulin content retained water during storage, regardless of the nature of the calcium salt used. In addition, they presented lower loss of elasticity and cohesiveness than the control crumb. Crumbs with calcium citrate and low inulin content produced the lowest increase in crumb firmness. In addition, elasticity and cohesiveness of crumbs containing low amount of inulin and organic salts were almost maintained. The salt that favored the retrogradation process was calcium lactate with high inulin content, evidenced by the shorter half-time obtained with the kinetic studies. Also, the increase in crystallinity of B-type starch in crumbs with organic calcium salts and high inulin content, correlates with the highest values of retrogradation enthalpy obtained by DSC.     

A method for the determination of acrylamide in bakery products using ion trap LC-ESI-MS/MS

Acrylamide levels of bakery products, e. g., bread and bread rolls, are usually below 100 microg/kg , often even below 50 microg/kg. Therefore, usual analytical methods which have an LOQ greater, not dbl equals 25 microg/kg are not sensitive enough for detailed investigations on acrylamide formation within these commodities. An improved method for trace level determination of acrylamide in bakery products was developed using ion trap LC-ESI-MS/MS. Samples were divided into crumbs and crusts to achieve an initial concentration by removing the crumbs since these are devoid of acrylamide. After sample extraction and clean-up using multimode SPE cartridges, further analyte enrichment was accomplished by solid-phase-supported liquid-liquid extraction with ethyl acetate prior to LC-MS/MS analysis. The method was evaluated using bread, bread rolls, alkali-baked bread rolls, and toast. LOQ was calculated from the confidence interval of the calibration curve and found to be 1.7 ng/mL, corresponding to 17 microg/kg of product. When crumbs and crusts were separated, an LOQ of 10.2 microg/kg of bakery product could be obtained. As demonstrated in preliminary comparative analyses, accuracy of the method met the requirements for determination of trace level acrylamide formation in bakery products. Mean recovery was 102.4% (CV 4.5%), intermediate reproducibility revealed a CV of 2.1%, and a repeatability of CV 6.0%.