Submitted to: Journal of Food Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 5/20/2005
Publication Date: 8/19/2005
Citation: Fan, X. 2005. Impact of ionizing radiation and thermal treatments on furan levels in fruit juices. Journal of Food Science. 70(7):E409-E414. Interpretive Summary: Furan, a toxicant, is listed as ‘reasonably anticipated to be a human carcinogen’ by the U.S. Department of Health and Human Services. A recent survey by the Food and Drug Administration (FDA) revealed furan is present in a wide variety of foods that undergo heat treatment. This study was conducted to investigate possible formation of furan in fruit juices as a result of ionizing radiation, a non-thermal processing technology used for enhancement of food safety and extension of shelf-life. Our results showed that irradiation and thermal treatments induced furan in both apple and orange juices. The furan levels induced by irradiation at doses that are sufficient to inactivate 99.999% of common forborne pathogens were comparable to those found in the FDA survey. Our result will help federal regulatory agencies to make science-based decisions on the evaluation of petitions to allow irradiation of ready-to-eat foods.
Technical Abstract: The formation of furan in freshly-prepared apple and orange juices as affected by ionization radiation and thermal treatments was studied using a newly developed solid phase microextraction method coupled with GC-MS. Results show that furan levels increased linearly as radiation dose increased from 0 to 5 kGy. Irradiation induced more furan in apple juice than in orange juice. During post-irradiation storage at 4°C, furan levels increased in both apple and orange juices, particularly in the first three days. On the other hand, irradiation degraded deuterated furan (d4-furan) spiked in water and fruit juices. The rate of degradation as a function of radiation dose was the highest in water, and the lowest in orange juice. Submerging the juice samples in boiling water for 5 min induced higher amounts of furan in orange juice than in apple juice, but autoclaving (121°C, 25 min) resulted in more furan formation in apple juice than orange juice. Our results suggest that both ionizing radiation and thermal processing induced furan formation in fruit juices.