A method for making pelleted animal feed and the product made by the method, comprising: preparing a composition containing a) 10-90 wt. % of an organic acid selected from the group consisting of acetic, propionic, butyric and mixtures thereof, b) I-90 wt. % of ethoxylated castor oil surfactant having an HLB from 4 to 18 and a molar ratio of 1 molecule of castor oil to 1-200 molecules of ethylene oxide, c) 0-20 wt. % of antimicrobial terpenes, or essential oils; adding water to prepare a heat-treating composition, and applying an effective amount of said heat-treating composition to an animal feed, with sufficient heating to pelletize or extrude the feed.