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探索和揭示了温度与三乙醇胺-盐酸缓冲溶液pH值、温度与糖液pH值、糖液pH值与色值、温度与色值的关系。经实验证明,在白砂糖色值测定过程中,如采取适当措施,可避免温度变化对测定结果的影响,从而可提高分析准确度。 相似文献
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本文基于制糖生产实际测定数据,首次引用灰色系统理论,对甜菜制糖生产流程中可能影响成品绵白糖色值的23个因素进行了系统研究,得出了诸因素对成品绵白糖色值影响的关联序。对成品绵白糖色值影响较大的因素为二清汁碱度、二砂糖色值、二清汁色值、一清汁碱度、硫漂汁色值,并借助于灰关联度矩阵,找出了影响成品绵白糖色值的诸因素之间的相互关系,为甜菜糖生产及产品质量的控制提供了科学依据和进一步研究的参考。 相似文献
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评价食糖质量优劣至关重要的指标是:糖分、水分、还原糖、色值和灰分。通过对1995/96生产期几项指标监测结果进行统计分析,白砂糖和绵白糖各月份每项检测结果的平均值均符合国家食糖标准。除色值外各月份数据变化稳定,色值则表现明显差异性。 相似文献
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为了提高苹果汁的色值,采用活性炭吸附.分别考察了活性炭目数,活性炭添加量,吸附温度对色值的影响.得出最佳的吸附目数和添加量组合是:80目,添加量为0.015g/mL.吸附温度对果汁色值的影响是温度越高,果汁色值越低. 相似文献
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色值是糖厂化学管理工作中衡量白砂糖质量的一项重要指标。通过两种测定方法相比较,发现采用三乙醇胺与盐酸配成的缓冲溶液直接溶糖的方法代替用氢氧化钠溶液或盐酸溶液调节糖液pH值的方法来测定白砂糖色值,省去每次测定都要调节糖液pH值的繁琐过程,又避免pH值调节引起的测定误差,提高分析的速度和准确度。 相似文献
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本文主要探讨白砂糖中酚类物、氨基态氮、铁离子对白砂糖色值的影响,结果显示,酚类物、氧基态氮是影响白砂糖色值的重要组分,铁离子是白砂糖贮存过程中增色的重要因素。 相似文献
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在100L规模上,通过五因素五水平二次旋转正交组合试验设计,探讨了挤压膨化大米辅料酿造啤酒的外加酶糖化工艺参数对啤酒色度的影响规律,得出最佳的糖化工艺参数。 相似文献
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对提高测色系统应用精确性的途径和方法,以及利用测试结果进行色光调整作了探讨,结果表明应用测色配色系统减少了人为因素的干扰,提高了染色过程中颜色的精确度。 相似文献
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通过分析古玉器的颜色来鉴别、评估古玉器是古玉器鉴定研究中的一项重要内容。出土古玉器的颜色成因是多方面的,既有玉料本身具有的颜色(作者称之为料色),它由玉石中所含致色元素的成分和质量分数决定;又有玉料被加工成器后因埋藏与周围介质发生作用而变化的颜色(即沁色)。在鉴定实践中不少的鉴定者将玉器的料色误定为沁色。以和田玉为例试图通过玉器的颜色与玉器雕琢纹饰之间的关系来辨别料色与沁色。 相似文献
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Cabrita AR Maia MR Freitas M Abreu JM Fonseca AJ 《Journal of the science of food and agriculture》2011,91(9):1648-1652
BACKGROUND: Dry corn gluten feed (CGF) is a raw material commonly included in compound feeds, particularly for ruminant animals. Its colour can vary from yellow–light brown to dark brown. A general assumption is that darker CGF has a low nutritive value for animals due to heat‐damaged protein. This study aims to evaluate the use of colour as a practical guide for estimating CGF protein value. RESULTS: Results indicate great variability in the physical and nutritional properties among 28 sources of CGF. Principal component factor analysis was used to reduce a large number of variables into fewer numbers of factors. First factor aggregated 1/Z and acid detergent insoluble N content in opposition to X, Y, eL, and L. Second factor aggregated a, a*, neutral detergent fibre and soluble crude protein (CP) contents in opposition to ash and CP contents, and digestible N and in vitro organic matter digestibility. Multiple regression analysis also showed that physical appearance (colour) was related to nutritional properties, stronger relationships being found between a, a* and L scores and digestible N. CONCLUSION: Colour could potentially be used to quickly predict the nutritive value of CGF, particularly digestible N, a key parameter when formulating rations. Copyright © 2011 Society of Chemical Industry 相似文献
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目前的翡翠市场暂时未建立起评价绿色翡翠颜色的统一标准。基于HSL色度学的绿色翡翠颜色分级理论与技术,本研究拟采用机器视觉法。根据色度学原理,以HSL颜色空间模型为理论基础,在色温5 500K白光光源下,通过彩色数码摄像头采集绿色翡翠样品的色彩,对每个样品图像颜色进行HSL值分析,从而量化绿色翡翠颜色的参数指标,并将所得到的HSL数值按不同色相(H)投点到二维的SL图像上,得到翡翠绿色色彩的HSL分布区间及其色度学特征,确定绿色翡翠各种色彩类型的HSL值边界,从而区分和确定绿色翡翠的色调,划分绿色翡翠的颜色浓度和明亮度,量化绿色翡翠的色彩类型。 相似文献
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Bett-Garber KL Champagne ET Thomson JL Lea J 《Journal of the science of food and agriculture》2012,92(2):283-291
BACKGROUND: The whiter the rice, the more it is preferred by consumers and the more value it has in the market place. The first objective of this study was to determine the interrelationships of raw colour, cooked colour, amylose content and protein content in rice. The second objective was to assess whether or not the colour of cooked rice can be predicted from raw rice colour in conjunction with amylose and protein contents. RESULTS: Protein and amylose contents were not significantly correlated with the colour measurements for raw rice. Protein and amylose showed moderate, significant associations with L* and a* and a*, b* and C* respectively for cooked rice. Only the colour variable a* of cooked rice could be predicted using protein, amylose and raw rice colour with high enough precision to be useful, and this was only for modelling using samples cooked in the same manner (rice cooker). Cooking method (rice cooker versus excess water) affected the colour of cooked rice. CONCLUSION: Being able to predict a* in cooked rice is likely of limited value. Only the model that used samples where postharvest handling conditions were controlled (US‐grown rice) was able to predict C*, a more useful measure, and then with only moderate ability. L*, a measure of brightness/whiteness, was not predicted well by any of the models. Copyright © 2011 Society of Chemical Industry 相似文献
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从分析产生色差的设备因素着手,论述浸轧染色、巨型卷染、冷轧堆染色等染色装备防患色差的技术更新,阐述了防患色差的一些方法。 相似文献