The simplest form of chromatography is the thin layer chromatography (TLC). A TLC plate consists of a glass or aluminium-backed strip that is coated with an adsorbent material, most commonly silica or alumina, which acts as the stationary phase in the separation. Using high-performance TLC (HPTLC), a quantitative analysis of a reaction mixture can also be obtained, though the advantages of being quick and easy are lost. This technique is carried out using a thinner stationary phase with a smaller particle size compared to traditional TLC. Electron capture detectors (ECD) are useful when analyzing compounds that contain functional groups with high electron affinity, such as conjugated carbonyls, halogens, nitriles, nitro compounds and organometallic compounds. Depending on the source and composition of the food waste being assessed, this detector will have varied levels of use.