Aflatoxins degradation and quality evaluation in naturally contaminated rice by dielectric barrier discharge cold plasma

Abstract

In this study, dielectric barrier discharge (DBD) cold plasma was explored for degrading aflatoxins in naturally contaminated rice. Rice samples were inoculated with strains of toxigenic Aspergillus and incubated to produce various levels of aflatoxins. Cold plasma showed degradation rates of aflatoxin B₁ (AFB₁) and total aflatoxins (AFs) that were related to moisture content, oxygen content, treatment time and voltage. Generally, the treatment reduced 1.08%–55.34% of AFB₁ and 4.23%–56.37% of AFs in rice under different conditions. Relative lower degradation rates can be due to low permeability of the plasma and interference from food matrix. In addition, no significant difference (P > 0.05) was found in moisture, protein, amylose and color of rice before and after treatment. However, cold plasma aggravated the fat oxidation of rice, and made its surface smoother and more porous. The results provided a theoretical basis for aflatoxins degradation from grain system using cold plasma.

Industry relevance

In this study, dielectric barrier discharge (DBD) cold plasma was applied in the degradation of aflatoxins in naturally contaminated rice, having obvious degradation effect and little quality impact. Cold plasma treatment, as a novel non-thermal processing technology, can reduce mycotoxins in food in order to fully ensure the product safety in various links, including production, storage and so on. Compared with other detoxification methods currently used in the industry, this technology can achieve similar or higher degradation effect in a shorter time. In addition, it is low-cost and will not pollute the environment or damage the sensory properties and nutritional value of products.