Wehling R L, Pierce M M
University of Nebraska, Department of Food Science and Technology, Lincoln 68583-0919.
J Assoc Off Anal Chem. 1988 May-Jun;71(3):571-4.
Near infrared reflectance (NIR) spectroscopy was used to determine the moisture content of Cheddar cheese. Through multiple linear regression analysis, a 3-wavelength calibration was developed for use with a commercial filter monochromator instrument. For a validation set of 47 samples, the correlation coefficient squared (r2) between the NIR and oven moisture methods was 0.92, with a standard error of performance (SEP) of 0.38%. Sample temperature was found to significantly affect the spectral response; therefore, it was necessary to equilibrate all samples to a uniform temperature prior to NIR analysis. Aging may also affect the NIR characteristics of cheese, although it was possible to develop a successful calibration that encompassed a wide range of aging times.
近红外反射（NIR）光谱法用于测定切达干酪的水分含量。通过多元线性回归分析，开发了一种用于商业滤光片单色仪仪器的三波长校准方法。对于47个样品的验证集，NIR法与烘箱法测定水分含量之间的决定系数平方（r2）为0.92，性能标准误差（SEP）为0.38%。发现样品温度会显著影响光谱响应；因此，在进行近红外分析之前，有必要将所有样品平衡至均匀温度。陈化也可能影响奶酪的近红外特性，不过有可能开发出一种成功的校准方法，涵盖广泛的陈化时间范围。
