Though more traditional paprika can be made from Aleppo, Hungarian, and a range of other peppers, herb and spice company McCormick’s Science Institute (MSI) says the mass-made stuff “is typically made from ‘bell’ or ‘sweet’ type peppers, milder varieties that contain a recessive gene that eliminates (or greatly reduces) capsaicin, the compound responsible for heat.”
Article source: https://www.huffingtonpost.co.uk/entry/paprika-pepper-food-sauce-ingredient_uk_6a046b32e4b0cdaf88dc7718