Mold Content of Commercial Popcorn ^†

Area of Science:

• Food Microbiology
• Mycology
• Agricultural Science

Background:

• Mold contamination in food products like popcorn can impact quality and safety.
• Understanding the prevalence and types of molds in different popcorn varieties is crucial for quality control.

Purpose of the Study:

• To determine and compare internal mold infection levels in various popcorn types.
• To identify the predominant mold genera and species affecting these popcorn varieties.
• To evaluate the efficacy of different culture media for mold enumeration.

Main Methods:

• Direct plating of kernels from microwave yellow, nonmicrowave white, nonmicrowave yellow, and specialty popcorn on four selective agar media (DRBC, DG-18, AFPA, CZID).
• Quantification of total mold-infected kernels and identification of dominant mold genera (Fusarium, Aspergillus).
• Isolation and identification of specific Fusarium species, with a focus on F. moniliforme.

Main Results:

• Total mold infection was higher in specialty (13.6%) and nonmicrowave white (15.1%) popcorn compared to microwave yellow (5.9%) and nonmicrowave yellow (7.3%) popcorn.
• Fusarium species predominated in microwave yellow and nonmicrowave white popcorn, while Aspergillus species were more prevalent in nonmicrowave yellow and specialty popcorn.
• Fusarium moniliforme was the most common Fusarium species across all popcorn types, with negligible presence of the Aspergillus flavus-parasiticus group.

Conclusions:

• Popcorn variety influences internal mold infection levels and the predominant mold genera.
• Fusarium moniliforme is a significant mold contaminant in various popcorn types.
• While DG-18 effectively enumerates Aspergillus, no single medium showed superiority for enumerating both Aspergillus and Fusarium species in popcorn.