The present disclosure relates generally to peroxyformic acid forming compositions and methods for forming peroxyformic acid, preferably in situ, and peroxyformic acid formed by said compositions and methods for the purpose of treating an animal tissue and providing an antimicrobial function thereon. present disclosure in particular relates to a residue-free teat treatment composition for the treatment of an animal tissue, especially bovine teats, which provides antimicrobial efficacy and does not leave a non-food ingredient residue on treated teats.