Growth, Sporulation and Aflatoxin Production by Aspergillus parasiticus on Strained Baby Foods

The potential for aflatoxin production by Aspergillus parasiticus on strained baby food was evaluated. Four puréed foods were inoculated with the mold and cultured at 15 and 26 C in two series of experiments. The aflatoxigenic mold produced mycelia and sporulated at both temperatures. The foods ranked in mean total yield of aflatoxin (μg/g of substrate) in the following order: peas > squash > green beans > pears. The ranking held consistent for both temperatures. Aflatoxins B₁ and G₁ were produced in higher percentages than B₂ and G₂ in each food at both temperatures. At 26 C, total aflatoxin produced ranged from 8 to 71 μg/g of substrate, and at 15 C, the mean for the four foods was from 3 to 50 μg/g of substrate. Temperature and substrate were the primary variables which contributed to sporulation rate, toxin production and toxin ratios. Peas and squash should be considered primary and highly supportive substrates for aflatoxin production if conditions should arise for spores to contaminate the products either during or after processing. Absolute prevention of aflatoxigenic spore contamination in these foods studied is essential. An occasional testing of these foods for aflatoxin seems warranted. A lower temperature during aflatoxin formation decreased the total toxin formed, but did not prohibit aflatoxin occurrence. A lower temperature also tended to divert the type of toxin produced from B₁ to the less dangerous G₁ and G₂. Aflatoxin would appear to be a problem in these foods only under rare and unusual circumstances in relation to processing and consumer usage. If such aflatoxigenic spore contamination should occur, the levels produced would be significant.