巧克力"起霜"现象的探讨

香醇浓郁的巧克随着质量的提高，不断受到人们的欢迎。但在其发生的各种质量问题中，“起霜”现象占的比例最高，对巧克力的影响也是最重要的。如何有效防止起霜是巧克力制造业需待解决问题。该文探讨了巧克力“起霜”的原因，对“起霜”巧克力的质地和风昧做了感官评定，并提出相应延缓巧克力“起霜”的方法。     

巧克力"起霜"现象的探索

香醇浓郁的巧克随着质量的提高,不断受到人们的欢迎。但在其发生的各种质量问题中,“起霜”现象占的比例最高,对巧克力的影响也是最重要的。如何有效防止起霜是巧克力制造业需待解决问题,该文探讨了巧克力起霜的原因,对起霜巧克力的质地和风味做了感官评定,并提出相应延缓巧克力起霜的方法。     

巧克力样品中反式脂肪酸含量的测定

采用气相色谱内标法,对20个巧克力样品中的反式脂肪酸含量进行测定分析。试验结果表明,以代可可脂为主要原料的巧克力样品中,反式脂肪酸含量范围在未检出至4．96％之间。以可可脂为主要原料的巧克力样品中,反式脂肪酸含量范围在未检出至0．844％之间。所测定的巧克力样品中反式脂肪酸以反十八碳一烯酸为主。     

Determination of Tangerine Volume Using Image Processing Methods

In this study, two image processing techniques; namely, segmentation and ellipsoid approximation, were used to estimate the volume of tangerines. The proposed system consisted of two CCD cameras, capture cards, an appropriate lighting system and a computer. The paired t-test showed the estimated volume using segmentation method was not significantly different from the volume determined by water displacement method (p > 0.05). The difference between the volumes estimated by ellipsoid approximation and water displacement method was statistically significant (P < 0.05). The Bland–Altman approach showed the size of tangerines has no effect on the accuracy of volume estimation by segmentation method.     

Characterization of the Jagged Stress-strain Relationships of Puffed Extrudates using the Fast Fourier Transform and Fractal Analysis

The jaggedness of the stress-strain relationship of two kinds of puffed extrudates stored under different humidity conditions was assessed by the power spectrum of the Fast Fourier Transform and the Natural Fractal dimension of normalized compression curves. Both analyses, performed with a micro-computer, provided a consistent measure of jaggedness. The apparent Fractal dimension, obtained using the Blanket algorithm, was the most convenient measure of overall ruggedness since it was expressed by a single number. The power spectrum that resulted from the Fourier transform, however, could be used to identify the length scale of structural features where fracture takes place, and its shape could be more directly related to structural features and textural properties.     

巧克力中砷含量的石墨炉原子吸收测定

研究了用石墨炉原子吸收法测定巧克力中砷的含量,采用氧化镁添加-干式灰化法消解样品,有效地抑制了砷的挥发；添加硝酸镍大大提高了石墨炉工作程序中的灰化温度,消除了样品基体中磷的干扰。此方法亦适合于其它高含磷样品的砷的测定。     

数字图像分析法在片烟结构测定中的应用

利用数字图像分析法探讨了片烟结构检测的新方法.结果表明:①图像分析法可以用于片烟结构的检测;方法的测试精密度范围是1.31～31.91 mm2,其大小与面积水平有关;②测试方法的相对误差在面积大于817.95 mm2时小于1％,在面积小于361.00 mm2时小于4％;③方法所需样品量应不少于1500g.     

傅里叶描述子在商标图像分类中的应用

针对单封闭轮廓的商标图像的分类,可以提取目标图像轮廓的傅里叶描述子作为特征向量,该描述子不会随着图像的旋转、缩放和平移而发生改变,把它作为形状特征描述来训练分类器。傅里叶描述子是商标图像外围轮廓较为重要的特征信息,体现着商标图像的全局特征。在支持向量机分类器的应用中不存在过学习和局部最小的问题,但其核函数及参数的选取尚没有较好的理论支持。     

基于绉织物表面图像分形特征分析的绉效应评价

通过MATLAB对绉织物表面图像进行处理,根据分形理论对绉织物表面图像的起绉纹理进行分析。结果表明,绉织物表面具有最著的分形特征,且绉织物的起绉程度与绉织物表面的视觉风格存在一定的关系,起绉程度大的绉织物其维数大于起绉程度小的织物。     

纤维横向尺寸SEM图像分析技术

本文简要介绍了用SEM图像分析评价纤维横向尺寸的技术，并分析了产生误差的主要因素。     

烟霜的化学成分分析

为了解雪茄烟叶烟霜的化学组成,采用原子吸收光谱法、离子色谱法、紫外可见分光光度法和气相色谱/质谱法测定了烟霜中的离子和挥发性有机化学成分。结果表明:烟霜中检出Ca2+,Mg2+,K+,Na+,NH4+,PO43-,C l-,NO3-,NO2-和SO42-等无机离子,其相对含量各为4.5%,0.9%,22.5%,2%,9.4%,0.4%,9.9%,33.2%,1.5%,3.8%,共约占烟霜重量的88%;烟霜中的挥发性成分以赤藓糖醇、l-苏糖醇、木糖醇和dl-苏丁醇等为主,另外还有少量的烷烃类。雪茄烟叶烟霜是一种由硝酸钾、氯化铵和少量的挥发性有机物组成的混合物。     

对粘胶纤维在高温灭菌后白度大幅下降原因的分析

本文针对粘胶水刺非织造布高温灭菌后白度大幅下降的现象进行了分析 ,找出了粘胶纤维白度下降的主要原因 ,并制定了相应的工艺有效地加以控制 ,提高了产品的质量     

图像分析测定红麦硬度方法的研究

本研究针对40种红麦，测定了其抗粉碎硬度指数、以此表示其硬度；同时，在一定的条件下，使用扫描仪采集经不同方法处理的红麦的反射图像，分别对每种不同处理的红麦反射图像进行分析，获取色泽参数，将色泽参数与抗粉碎硬度指数线性回归。实验结果显示，对不同处理的红麦所获得的图像都有色泽特征参数，其相关性十分显著（r为0.9以上，n=40）。而且彩色特征色值回归系统比灰度值大。     

微度漂白浆生产纸袋纸的白度控制

介绍了微度漂白浆生产纸袋纸过程中白度的影响因素及控制方法；为本色浆产品市场拓展提供了新思路。     

Rapid Determination of Total and Solid Fat Contents in Chocolate Products by Pulsed Nuclear Magnetic Resonance

A rapid pulsed NMR method of fat analysis in chocolate without prior solvent extraction was developed. Total fat content of 43 chocolate products was determined at 60°C using sucrose-oil mixtures as standards. Solid fat content (SFC) was calculated from the liquid oil content at different temperatures. Total fat content agreed to 0.90% standard error of prediction as compared with the Soxhlet method. SFC as determined by NMR correlated well with the dilatometry (r = 0.98) and the DSC (r = 0.96) results. This technique is suitable for quality control of chocolate and other lowmoisture, high-fat products.     

浅析抗结剂添加量对食用盐白度和抗结效果的影响

添加剂的添加量会影响食用盐的白度。笔者在此基础上进行了更进一层的分析,通过多次试验检测得出了在成品盐粒度均匀的情况下不同抗结剂的添加量的有效控制范围,使之既满足国家标准添加要求,又能满足食盐抗结和白度要求。     

Determination of the Collagen, Elastin and Bone Content in Meat Products using Television Image Analysis

Television image analysis offers a method for the automatic determination of surface areas. The method was tested for its suitability for use in the quantitative estimation of raw and gelatinized collagen, elastin and bone particles of histological sections of meat and meat products. Five different experiments show that television image analysis correlates closely to the results obtained using the point count technique (correlation coefficient r > 0.981), the bone content determined by chemical means (r > 0.97) as well as the experiments using added collagen (r = 0.988) and elastin (r = 0.854). It can be concluded that the automatic image analysis is an adequate alternative to chemical analysis.     

Comparison of Six Methylation Methods for Fatty Acid Determination in Yak Bone Using Gas Chromatography

Yak bone is rich in nutrition but not used efficiently. Six methylation methods (M1: acetyl chloride-methanol method, M2: H₂SO₄-methanol method, M3: HCl-methanol method, M4: KOH-methanol method, M5: M2 in combination with M4, and M6: M3 in combination with M4) with (system 1 (S1)) or without (system 2 (S2)) prior acid hydrolysis for fatty acid (FA) determination using gas chromatography in yak bone were comprehensively compared. The contents of total FA determined by using M1 and M2 were significantly higher (p < 0.05) than those by using M3 for both S1 and S2 (119.83 versus 118.34 versus 38.31 mg/g in S1; 104.03 versus 93.73 versus 30.08 mg/g in S2 for M1 versus M2 versus M3, respectively). The result determined by M4, M5, and M6 was less than 5 mg/g. Validation results of M1 and M2 indicate that for most (>90%) of the FA, the intra-day and inter-day CVs were <9%. Recoveries for more than 90% of the FA were within a range of 85–117%. In addition, C18:1n9c, C16:0, C18:0, and conjugated linoleic acid were the major FAs in yak bone, approximately accounted for 50, 20, 10, and 10% of the total FA, respectively. And the ratio of saturated and unsaturated FA in yak bone was about 1:2. The acid hydrolysis/H₂SO₄-methanol esterification method would be more efficient for the accurate determination of FA in yak bone, whereas the direct acetyl chloride-methanol method would be used as an alternative for the fast analysis.     

金属漂白活化剂对氨纶弹性织物白度影响及机理分析

为了解金属漂白活化剂体系对氨纶弹性织物白度的影响,通过在两类不同洗涤剂(分别含漂白剂和生物酶)中添加漂白活化剂,对氨纶弹性织物和氨纶丝进行模拟家用低温洗涤,利用测色配色仪测试织物和氨纶丝洗涤前后白度变化,通过采用FITR-ATR,SEM测试方法对氨纶纤维进行分析表征.结果表明:在含漂白剂成分的洗涤剂中添加金属漂白活化剂,可提高织物白度,但随洗涤次数增加织物白度反而降低,在洗涤过程中过强的活性氧会造成氨纶丝氧化损伤,分子中异氰酸酯被氧化生成有色物质;在含生物酶洗涤剂中添加金属漂白活化剂,不能提高织物白度.