Patent ID: 8277733

Claim:
A method for treating food packages comprising: (a) providing a liquid composition of a carboxylic acid and an oxidizing agent; (b) pretreating the carboxylic acid with a first pretreatment column to remove metal ion from the carboxylic acid, wherein said first pretreatment column comprises a removable pretreatment cartridge; (c) measuring the pressure of the carboxylic acid (i) before pretreating, and (ii) at site of pretreating during pretreating; (d) determining a difference between (i) and (ii); (e) reacting the liquid composition in the presence of a reaction catalyst in a first reaction catalyst column to produce a peroxycarboxylic acid composition; (f) applying the peroxycarboxylic acid composition to a food package; and (g) recovering the peroxycarboxylic acid composition.