Detoxification of Aflatoxin B1 on Dried White Mulberry (Morus alba L.) Using Dielectric Barrier Discharge Plasma

Background: Aflatoxin B1 (AFB1) is an extremely toxic mycotoxin usually found in dried fruits, including mulberries, posing significant health risks. This study investigated the potential of cold plasma treatment to decrease AFB1 contamination in dried white mulberries (Morus alba L.) and its effects on product quality. Methods: A total of 5 kg of fresh white mulberries were harvested at full ripeness from Urmia, Iran, during June–July 2023. The fruits were sun-dried using traditional methods and artificially contaminated with AFB1 (2000 µg/kg). Samples (5 g per replicate, total n = 51) were treated using a cold plasma jet system positioned 1 cm above water-containing glass beakers with mulberries immersed in water. Treatments were applied at voltages of 5, 9, and 13 kV for 6, 12, and 18 min according to a Central Composite Design. AFB1 levels were quantified by High-Performance Liquid Chromatography coupled with immunoaffinity column cleanup. Quality parameters including pH, Total Phenolic Content (TPC), and color (L*) were measured. Statistical analysis was performed using Design-Expert software version 13 (Stat-Ease, Inc., Minneapolis, USA), employing analysis of Variance (ANOVA) and regression modeling. Results: Cold plasma treatment decreased AFB1 content by up to 62.6% at 13 kV and 18 min. pH decreased due to the combined effects of treatment time and voltage, whereas TPC decreased significantly with each factor individually, whereas color (L*) showed no significant change (p>0.05). Conclusion: Cold plasma effectively reduced AFB1 contamination in dried mulberries with minimal impact on color but caused decreases in pH (from 5.18 to 4.12) and TPC (by approximately 32%), indicating some quality degradation. Further studies should evaluate sensory attributes, microbial safety, and storage stability to confirm industrial applicability.