Application of light based, non-thermal techniques to determine physico-chemical characteristics, pungency and aflatoxin levels of dried red chilli pods (Capsicumannuum)

Abstract

Aflatoxin contamination is a significant barrier in the international trade of major spices like chilli, aniseed, and pepper. Hence, it is crucial to develop effective aflatoxin decontamination management strategies to enhance the export potential of Indian spices. However, traditional methods employed for aflatoxin reduction significantly impact the characteristics of chilli. Thus, an investigation was conducted to determine the effectiveness of non-thermal, light-based techniques such as UV-C, blue LED and atmospheric plasma in reducing the aflatoxin concentration in dried chilli. The LED treatment at 3.4 V significantly increased the β-carotene content of chilli. Similarly, the atmospheric plasma treatment reductant increased the volatile oil and carotenoid content by 75% and 39%, respectively. In addition, the LED treatment significantly increased the pungency characteristic of chilli by 163% when compared to the control sample. Further, the chromatographic analysis confirmed the increase in capsaicin content of red chilli by 20% and 41% after UV-C and plasma treatment, respectively. UV- C radiation for 90 min at 60W, blue LED light (25000 mcd radiant power) at 470 nm for 45 min and atmospheric plasma at 45 kV for 15 min resulted in the reduction of aflatoxin B1 content in chilli by 15%, 38% and 67%, respectively. Atmospheric plasma significantly reduced the aflatoxin content below the permitted limit according to FAO WHO standards (of 30 ppb) within a limited time.