ARS | Publication request: Effects of pulsed UV-light on peanut allergens in extracts and liquid peanut butter.

Submitted to: Journal of Food Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 26, 2008
Publication Date: June 12, 2008
Citation: Chung, S., Yang, W., Krishnamurthy, K. 2008. Effects of pulsed UV-light on peanut allergens in extracts and liquid peanut butter. Journal of Food Science. 73(5):C400-C404.

Interpretive Summary: Pulsed ultraviolet (PUV) light is a non-thermal high-peak power technology, that consists of intense flashes of broad-spectrum white light. Because of its high-peak power, PUV-light has been successfully used as a sterilization tool to kill bacteria and fungi in foods and fruits. However, very little is done or known about the effect of PUV-light on proteins, in particular, the peanut allergens that cause peanut allergy. In this study, we hypothesized that PUV-light may lower the allergenic potency of peanut extracts and liquid peanut butter, based on the rationale that it transforms peanut allergens into insoluble aggregates, or polymers that may be resistant to digestion and absorption by human guts. Results from treatment of both peanut extracts and liquid peanut butter with PUV-light, indicated that two major peanut allergens (Ara h 1 and Ara h 3) were affected by PUV-light. Another major allergen, Ara h 2, was unaffected. In-vitro studies (i.e., in test tubes) using a pooled serum from peanut-allergic individuals indicated that the allergenic potency of the PUV-treated peanut samples was 7-fold lower than that of the untreated. It was concluded that PUV-light was effective in reducing the allergenic potency of peanut extracts and liquid peanut butter. The research may find an application in the development of a hypo-allergenic peanut-based product or a health related beverage.

Technical Abstract: Pulsed ultraviolet (PUV)-light, a non-thermal technology, was used to treat both peanut extracts and liquid peanut butter. The objective was to determine if such treatment would lead to a reduction in the allergenic potency of the peanut extract and butter. Peanut samples were PUV treated, using a Xenon RS-3000C, under the following conditions: 3 pulses per sec, 14.6 cm from the central axis of the lamp, 4 min. (extract) or 3 min. (liquid peanut butter). After treatment, the peanut samples were centrifuged and the supernatants analyzed by SDS-PAGE and ciELISA. For comparison, boiling treatments were also performed. SDS-PAGE showed that while boiling treatment had little effect on the peanut allergens, PUV-light-treated samples displayed a reduced level of two major peanut allergens, Ara h 1 and Ara h 3. Another allergen, Ara h 2, was unaffected. Insoluble aggregates formed were responsible for the reduced level of allergens in PUV-light but not in boiling treatment. ciELISA showed that PUV-treated samples exhibited an IgE binding, or allergenic potency 7-fold lower than that of the control. It was concluded that PUV-light was effective in reducing the allergenic potency of peanut extracts and liquid peanut butter. The research may find an application in the development of a hypoallergenic peanut-based product or a health related beverage.