Effect of dielectric barrier discharge high voltage atmospheric cold plasma on Aspergillus flavus inactivation and aflatoxin B1 degradation on inoculated raw peanuts

High voltage atmospheric cold plasma (HVACP) is an emerging non-thermal technology with short treatment time, low energy consumption, and no chemical residues on foods. Peanut samples inoculated with Aspergillus flavus spores and spiked with Aflatoxin B₁ (AFB₁) toxin were treated with HVACP at 90 kV for 2, 5, and 10 min, and post-treatment storage times (0, 4, and 24 h) using air with different relative humidities (RH, 5, 40, and 80 %), respectively. A treatment of 5 min resulted in a 2.20 log spores reduction of A. flavus spores on peanuts. A. flavus was almost completely inactivated (99.9 %) by HVACP treatment for 10 min with 80 % RH in the air and 24 h post-treatment storage. A 71.3 % AFB₁ reduction was achieved with a treatment of 2 min and 80 % RH without post-treatment. The reduction of AFB₁ toxin also significantly increased with increasing treatment time, higher RH and post-treatment storage (p < 0.05). HVACP is a promising technology to effectively inactivate A. flavus and reduce AFB₁ on raw peanut kernels without adversely affected peanut quality.

Industrial relevance

To improve the food safety and quality, it is crucial to develop an effective microbial decontamination approach while having minimal impact on the organoleptic characteristics and nutritional value of treated foods. Peanuts are an excellent source of plant-based protein, but they are highly susceptible to contamination with Aspergillus spp. mold, which may lead food safety issues. Cold plasma as an emerging non-thermal technology with short treatment time, low energy consumption, and no chemical residue on the food proves to be a promising tool to effectively inactivate A. flavus and reduce AFB₁ on raw peanut kernels without adversely affected peanut quality.