Inhibition of mold growth and mycotoxin production in high-moisture corn treated with phosphates

Mold growth and mycotoxin production were studied in high-moisture (20%) corn treated with tetrasodium pyrophosphate (TSPP); acid and alkaline sodium polyphosphate, glassy (SPG), also known as sodium hexametaphosphate; sodium tripolyphosphate (STPP); and tricalcium phosphate. Six mold cultures belonging to the genera Aspergillus, Fusarium, and Penicillium were tested in corn varieties highly resistant or highly susceptible to mold infection in the field, and in a mixture of five other varieties of corn. The acidic SPG, as well as TSPP and STPP totally prevented or reduced mold growth when added in powder form to corn at 1.0% or 2.0% (w/w), regardless of corn variety and high moisture content. Phosphates afforded protection in whole and damaged kernels. Similar results were obtained with 2.0% acidic SPG and TSPP when added in spray form. Whenever mold growth occurred, treatment of corn with 1.0% or 2.0% (w/w) TSPP and acidic or alkaline SPG inhibited (P0.01) aflatoxin production by aspergilli