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外文翻译求助，略急，求各位高手帮忙，谢谢
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2.5. Color, browning index and hidroxymethylfurfural determination Color was determined using a Hunter Labscan II spectrophotometric colorimeter (Hunter associates laboratory Inc., Reston, Virginia, USA) controlled by a computer that calculated color ordinates from the reflectance spectrum (Calvo & Duran, 1998) and calibrated with a white standard tile. Samples were placed in Petri dishes and filled to the top, and color was recorded using the CIELab uniform color space at room temperature. Color determined by CIE (Commission Internationale l’Eclairage) classifies color in three dimensions; L , brightness, a , red to green color and b , yellow to blue color. Chroma ((a + b ) ), that quantify color intensity, and total color differences ( E = L + a + b ), which indicate the magnitude of the color difference between juices at initial time and after the storage period, were also determined. The results were expressed in accordance with the CIELAB system with reference to illuminant D65 and with a visual angle of 10℃. The measurements were made in triplicate. Browning index: Non-enzymatic browning index is determined with an absorbance measure at 420 nm. Three milliliter of orange juice are centrifuged at 2000 rpm during 20 min at 18℃, and the supernatant is mixed equally distributed with ethanol 95%. After filtering the mixture, the absorbance is measured at 420 nm (Meydav, Saguy, & Kopelman, 1977). Hidroxymethylfurfural (HMF): Hidroxymethylfurfural content is measured using the method described by IFFJP (1984). This method is based in that HMF reacts with barbituric acid and p-toluidin, forming a red compound. This reaction has a maximum at 3–4 min. The Association ofthe Industry of Juices and Nectars from Fruits and Vegetables of the European Economic Community (AIJN, 1996) has included the amount of HMF among the absolute parameters of quality (620 mg/L) in the code of practice for the evaluation of fruits and vegetable juices. |
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RXMCDM: 金币+1, 多谢应助！ 2014-04-16 15:18:58
孙仙仙儿: 金币+80, 翻译EPI+1, ★有帮助, 谢谢啦， 2014-04-16 22:01:30
RXMCDM: 金币+1, 多谢应助！ 2014-04-16 15:18:58
孙仙仙儿: 金币+80, 翻译EPI+1, ★有帮助, 谢谢啦， 2014-04-16 22:01:30
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颜色、褐变指数和羟甲基糠醛的测定 使用Hunter Labscan II分光光度色度仪(Hunter associates laboratory Inc., Reston, Virginia, USA)测定，该设备与电脑相联，以白色标准瓷砖做校正，根据反射光谱计算色泽纵坐标。将样品至于皮氏培养皿中，并填满，室温下 使用国际照明委员会实验室均匀色泽空间记录色泽。用国际照明委员会在三维方向对色泽进行分类并测定色泽；L代表亮度，a代表红色到绿色，b代表黄色到蓝色。色度(a + b )表征色泽的浓度，总色差( E = L + a + b )表明果汁在一开始和储藏一段时间之后色差的大小。结果的表达与国际照明委员会实验室系统相一致。国际照明委员会实验室系统参考光源D65，可视角度为10℃。测定结果重复三次。 褐变指数：在420nm测定的吸光值即为非酶褐变指数。3ml橘汁18℃下2000 rpm离心20min，上清液与95%乙醇液等量混合，过滤混合液，在420nm下测定吸光值(Meydav, Saguy, & Kopelman, 1977)。 羟甲基糠醛(HMF)：羟甲基糠醛含量用IFFJP (1984)描述的方法测定。其原理是羟甲基糠醛与巴比妥酸p-对苯胺反应形成红色化合物，该反应反应3-4min时产生最大值。对于对于果蔬汁的质量评价欧洲经济共同体(AIJN, 1996)的果蔬汁工业协会规定HMF的数量为620 mg/L。 |
2楼2014-04-16 15:07:31
