Improving the safety of apple juice by UV irradiation

The higher incidence of patulin in apple juice has caused wide concern in the world. UV irradiation at 254 nm and 3.8 mW/cm2 of intensity was used to degrade patulin in apple juice, and the quality changes and safety of apple juice before and after UV detoxification were explored. The results showed that UV irradiation significantly decreased patulin in apple juice from 99.42 µg/L for the control sample to 16.98 µg/L after UV exposure for 5 min at UV intensity of 3.8 mW/cm2, and resulted in 82.92% reduction of patulin in apple juice, which is far below the limit level in apple juice (50 µg/L) set by BSDA and WHO. UV irradiation had no obvious effects on the soluble solids content and total phenol, and minor changes on reducing sugar, pH, total acids, and transmittance rate, while significant effects on color value and ascorbic acid of apple juice. UV irradiation for 15 min reduced significantly the toxicity of patulin in apple juice. All the results suggest that UV irradiation is a better choice to detoxify patulin in apple juice in fruit and vegetable juice processing industry.