There are three main classes of triglycerides—saturated fats, and unsaturated trans-fats and cis-fats. Unsaturation indicates the triglyceride contains one or more carbon–carbon double bonds. Most natural oils like vegetable oil consist of cis-fats and are poly-unsaturated, meaning they contain more than one double bond. The cis nature prevents solidification of the fat; trans-fats solidify more readily, which can lead to blockages in the bloodstream. Fourier transform infrared (FT-IR) spectroscopy functions well to analyse trans-fats.
The NIR (900–2500 nm) region was largely neglected by analysts for many years because of the complex nature of the spectra produced by water, proteins etc. in this region. However, thanks to the many and varied multivariate mathematical calibration approaches now available, broadly described by the term “chemometrics”, it has recently found new and important applications, particularly in the pharmaceutical and food industries for raw material and Quality Assurance procedures.
The determination of inorganic elements in food substances is critical for assessing nutritional composition and identifying food contamination sources. The measurement of inorganic elements is challenging because there is a wide variety of edible substances. As a result, highly diverse matrices must be analysed accurately. The different matrices can lead to numerous interferences on inorganic elements of interest and the interferences can vary with matrix composition.