Chapter 10 - Milk and Dairy Products

Abstract

Infrared (IR) spectroscopy plays a significant role in producing dairy products of high quality and consistency from farm to final product. Near-infrared (NIR) and mid-infrared (MIR) spectroscopy, are making new inroads into a range of applications in the dairy industry. These applications include process monitoring, determination of quality, geographical origin, and adulteration of dairy products in processes such as milk, milk powder, butter, and cheese production. NIR spectra and partial least squares (PLS) regression are employed to predict the total fat content of milk with a relative standard deviation of 2%. Fourier transform infrared (FTIR) spectroscopy can be used for the compositional analysis of sweetened condensed milk. Fat and total solids content can be predicted with accuracy in the order of ±0.09 and ±0.55 for fat and total solids respectively. MIR spectroscopy is employed to determine the fat and moisture content of butter samples. The MIR technique produces compositional values comparable to those obtained by conventional wet chemical methods. MIR spectroscopy can also be used for the quantitative analysis of edible trans fats in butter, and the characterization of butter, soybean oil, and lard. NIR spectroscopy can be employed to predict the solid fat content of milk fat extracted from butter during manufacture.