This document discusses the use of near-infrared spectroscopy (NIRS) for chemical analysis of feeds and foods. NIRS allows rapid, non-destructive testing of multiple components at once. It is faster and cheaper than traditional wet chemistry methods. NIRS works by measuring how organic compounds absorb near-infrared light. Absorption data is used to build calibration models that can then predict nutrient content of new samples. NIRS is advantageous as it provides real-time, multi-component analysis without chemicals or waste.