Papain is an enzyme collected from the latex of the papaya fruit (Carica papaya). It is a protease, meaning it cuts proteins into smaller pieces. In the Codex numbering system the 1101 series covers proteases, and sub-index (ii) names papain specifically; related forms include bromelain from pineapple, 1101 (iii), and ficin from figs, 1101 (iv). Codex lists papain as a flavour enhancer and a flour treatment agent.
It is best known as a meat tenderiser, but in snacks it works on wheat dough. By breaking down part of the gluten, it makes the dough softer and less elastic, so thin biscuits and sticks hold their shape instead of shrinking back after they are sheeted and baked. On SeekSnack it is listed as a flour treatment agent on Pocky Matcha Green Tea and Pocky Choco Banana.
Papain itself comes from a plant, but the dough it treats is made from wheat flour, which contains gluten.
