Abstract Optical back-scattering from milk with various fat and protein concentrations were evaluated in a back-scattering configuration using white, violet, blue, green, red or near infrared (NIR, λ = 850 and 940 nm) LEDs as the light source. The tip of the optical fibre bundle was dipped into the milk with fat and protein concentrations from 8.2 to 39 g L−1 and 32 to 37.7 g L−1, respectively. The back-scattering intensities varied linearly with the fat and protein concentrations of the milk. The slope (G) of calibration lines varied with the wavelength of the incident light. The G of the fat concentrations became zero at wavelength around λ = 520 nm and that of the protein concentrations was much smaller than that of the fat concentrations at NIR wavelengths. The fat and protein concentrations can therefore be measured separately based on the scattering intensities by selecting the wavelength for measurement.

中文翻译：

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基于后向散射强度的光纤评估的牛奶脂肪和蛋白质浓度的定量分析

摘要 在使用白色、紫色、蓝色、绿色、红色或近红外（NIR，λ = 850 和 940 nm）LED 作为光源的背散射配置中，评估了具有不同脂肪和蛋白质浓度的牛奶的光学背散射。将光纤束的尖端浸入脂肪和蛋白质浓度分别为 8.2 至 39 g L-1 和 32 至 37.7 g L-1 的牛奶中。反向散射强度随牛奶的脂肪和蛋白质浓度呈线性变化。校准线的斜率 (G) 随入射光的波长而变化。脂肪浓度的 G 在 λ = 520 nm 附近的波长处变为零，蛋白质浓度的 G 远小于 NIR 波长处的脂肪浓度。