Plant non-specific lipid-transfer proteins transfer phospholipids as well as galactolipids across membranes. May play a role in wax or cutin deposition in the cell walls of expanding epidermal cells and certain secretory tissues. Aleurone layer of developing and germinating seeds. During brewing process, structural and chemical modifications of the protein occur. Both unfolding of the structure and glycation should increased the amphiphilicity of the protein, leading to foam-promoting forms that concentrate in beer foams. Belongs to the plant LTP family. Was originally thought to be an inhibitor of alpha-amylase or of a protease and was known as PAPI: probable alpha-amylase/protease inhibitor. One beer please - Issue 48 of July 2004