Scoville scale more, depending on seed lineage, climate and humidity, and soil composition supplying nutrients. The inaccuracies described in the measurement methods also contribute to the imprecision of these values. "Capsicum" chili peppers are commonly used to add pungency in cuisines worldwide. The range of pepper heat reflected by a Scoville score is from 100 or less (sweet peppers) to over 3 million (Pepper X) (table below; Scoville scales for individual chili peppers are in the respective linked article). The class of compounds causing pungency in plants like chili peppers is called capsaicinoids, which display a linear correlation between concentration and Scoville
Scoville scale the parts-per-million by 16." HPLC results permit the measurement of a substance’s capsaicin capacity to produce perceived heat ("pungency"). This method yields results in American Spice Trade Association (ASTA) "pungency units", which are defined as one part capsaicin per million parts dried pepper mass. For parts per million (ppm) measurements: "Scoville Heat Units are calculated in parts per million of heat (ppm H) based on sample dry weight according to the following equation from ASTA (1985): ppm H = [Peak area of capsaicin + (0.82)(peak area of dihydrocapsaicin)](ppm standard)(ml acetonitrile) ÷ (Total capsaicin peak area of standard)(g sample). Conversion to