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11.
Samples of chicken meat from spent laying hens were obtained by four different methods: (1) manual deboning of whole carcasses; (2) manual deboning of skinned carcasses; (3) mechanical deboning of whole carcasses; and (4) mechanical deboning of skinned carcasses. The meat was packaged, frozen and stored at ?18 °C for up to 3 months. Functional properties studied were pH, emulsifying capacity (EC) and water‐holding capacity (WHC) and, in addition, pigment concentration was investigated. Sensory properties included aroma, colour, texture and overall acceptability, as judged by a trained panel using a nine‐point hedonic scale. Removal of the skin prior to deboning by either method gave significantly higher values (P < 0.05) for EC, while WHC values were not significantly different among the experimental treatments, despite higher pH values for mechanically‐deboned meat, with and without skin. Pigment concentrations were highest in meat from Treatment 4 and lowest for Treatment 1, but values for both methods of deboning were affected by the presence of skin. There were no significant differences between treatments for any of the sensory properties studied. Changes occurring in the meat during frozen storage are described.  相似文献   
12.
萝卜色素的性质研究   总被引:2,自引:0,他引:2  
本文报道了从红心萝卜中提取的花青素类红色天然色素的理化性质,包括光谱特性和溶液pH、金属离子及食品基质对萝卜色素呈色和稳定性的影响等。与其他来源的花青素类色素一样,随pH增大,最大光吸收波长(λmax)向长波方向移动。金属高子(Fe ̄(3+)、Cu ̄(2+)、Al ̄(3+))对该色素的稳定影响不大,蔗糖、NaCl、淀粉等食品基质能明显地增强萝卜色素水溶液的颜色。  相似文献   
13.
The mechanism of colour change during the pigment dispersion process and during powder application to the skin surface was studied by examining the colour extension properties of Yellow. Red , and Black iron oxides in white powder bases. A new measure for the evaluation of the degree of colour extension was devised. This measure corresponded well with human visual sensation, and was found to be useful for comparing the rates of colour extension of pigments. The rate of colour extension of pigments was found to vary in the order: Yellow acicular Red granular Red Black. This result explains colour darkening and the change towards reddish tones during the pigment dispersion process, because Yellow extends fully in the early stage of the process but Red , especially in granular form, and Black continue to extend even in the later stage. Acicular Red iron oxide is more favourably employed than the granular form to attain sufficient colour extension of foundations with lower energy expenditure, and to decrease the discrepancy between the cake colour and the colour of applied powder.
Le développement des oxydes de fer et effet sur les nuances des fonds de teint compacts  相似文献   
14.
介绍了用超声提取及大孔树脂分离山楂中主要成分的方法。该方法用60%乙醇超声提取,大孔树脂分离,30%乙醇洗脱主要含色素,60%乙醇洗脱主要含黄酮;用98%乙醇超声提取主要含三萜成分。本方法简单易行,提取效率也较高,适于大规模生产。  相似文献   
15.
本文综述了聚氨酯/聚丙烯酸酯互穿网络(IPN)涂料印花粘合剂。介绍了IPN粘合剂的制备方法及其不同配比时对拉伸强度、断裂伸长率、摩擦牢度性能的影响。IPN粘合剂可克服聚丙烯酸酯粘合剂的延伸性差、湿摩擦牢度低、易吸尘和粘搭性强的缺点,是改进聚丙烯酸酯类粘合剂性能十分有效的方法。  相似文献   
16.
Disruption of retinal pigment epithelial (RPE barrier integrity is a hallmark feature of various retinal blinding diseases, including diabetic macular edema and age-related macular degeneration, but the underlying causes and pathophysiology are not completely well-defined. One of the most conserved phenomena in biology is the progressive decline in mitochondrial function with aging leading to cytopathic hypoxia, where cells are unable to use oxygen for energy production. Therefore, this study aimed to thoroughly investigate the role of cytopathic hypoxia in compromising the barrier functionality of RPE cells. We used Electric Cell-Substrate Impedance Sensing (ECIS) system to monitor precisely in real time the barrier integrity of RPE cell line (ARPE-19) after treatment with various concentrations of cytopathic hypoxia-inducing agent, Cobalt(II) chloride (CoCl2). We further investigated how the resistance across ARPE-19 cells changes across three separate parameters: Rb (the electrical resistance between ARPE-19 cells), α (the resistance between the ARPE-19 and its substrate), and Cm (the capacitance of the ARPE-19 cell membrane). The viability of the ARPE-19 cells and mitochondrial bioenergetics were quantified with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and seahorse technology, respectively. ECIS measurement showed that CoCl2 reduced the total impedance of ARPE-19 cells in a dose dependent manner across all tested frequencies. Specifically, the ECIS program’s modelling demonstrated that CoCl2 affected Rb as it begins to drastically decrease earlier than α or Cm, although ARPE-19 cells’ viability was not compromised. Using seahorse technology, all three concentrations of CoCl2 significantly impaired basal, maximal, and ATP-linked respirations of ARPE-19 cells but did not affect proton leak and non-mitochondrial bioenergetic. Concordantly, the expression of a major paracellular tight junction protein (ZO-1) was reduced significantly with CoCl2-treatment in a dose-dependent manner. Our data demonstrate that the ARPE-19 cells have distinct dielectric properties in response to cytopathic hypoxia in which disruption of barrier integrity between ARPE-19 cells precedes any changes in cells’ viability, cell-substrate contacts, and cell membrane permeability. Such differences can be used in screening of selective agents that improve the assembly of RPE tight junction without compromising other RPE barrier parameters.  相似文献   
17.
叶黄素的提取及制备进展   总被引:7,自引:0,他引:7  
叶黄素是一种新型的食用功能型色素。可以从天然植物中提取含有叶黄素的酯类皂化制得。本文通过参考国外有关文献报道及国内实际情况。分析和阐述了提取及制备叶黄素的发展情况及适宜国内的技术方向。  相似文献   
18.
新型大红陶瓷色料的研制   总被引:1,自引:3,他引:1  
徐研  高雅春  李美霞 《陶瓷》2006,(4):24-27,44
通过在具有晶体结构的三元氧化物(ABO3)中添加少量的Cr^3+(钙钛矿)作为发色剂,可制得一种新型的大红陶瓷色料,在生成一次制品和一次性烧成砖的高温情况下,此色料色彩纯正,热稳定性好。  相似文献   
19.
采用液相反应法研制了釉上金红颜料,给出了颜料和熔剂配方及其制备方法。  相似文献   
20.
介绍了Kynar-500涂料的涂装工艺,并对涂层的性能作了试验与分析。  相似文献   
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