Use of Pulsed Ultraviolet Light to Reduce the Allergenic Potency of Soybean Extracts

Abstract

Pulsed ultraviolet light (PUV), a non-thermal food processing technology, is reported to be able to inactivate enzymes and reduce allergen levels from peanut extracts. The objective of this study was to determine if PUV would reduce the allergen levels and allergenic potency of soy extracts. Soy extracts were treated with PUV at various times (2, 4 and 6 min), centrifuged, and analyzed by SDS-PAGE and an indirect ELISA for IgE binding or allergenic potency. Results showed that PUV treatment led to an increase in sample temperature/weight loss but a decrease in the levels of soy allergens (i.e., glycinin and ?-conglycinin) as shown in SDS-PAGE. Allergens were reduced probably through aggregation which increased with treatment time. IgE binding was reduced as well in the following order: 20%, 44% and 50% reductions in absorbance values at 2, 4, 6 min, respectively (the latter two were not significantly different (p < 0.05%) from each other). It was concluded that PUV was capable of reducing the allergenic potency of soy extracts, and that the optimal PUV treatment time was 4 min. Clinical data is still needed before PUV can find an application in the development of less allergenic soybean beverages and products.

Soybean Allergens: Presence, Detection and Methods for Mitigation

“…The continuous system can also be used for batch treatment by setting the conveyor speed to zero. The PUV treatment is a process of photophysical, photothermal and photochemical effects (Chung et al, 2008;Krishnamurthy et al, 2009;Yang et al, 2010;Shriver and Yang, 2011). Normally, PUV is regarded as nonthermal as long as the duration of exposure is short (e.g., seconds), as the temperature rise is insignificant; however, a prolonged PUV exposure (e.g., minutes) can incur significant temperature rise and moisture loss of the sample, where both the nonthermal (mostly due to the UV spectrum) and photothermal (mostly from the infrared spectrum) effects co-exist ).…”

“…However, there may be other covalent modification involved in the process of PUV treatments. It is believed that PUV's photothermal, photophysical and photochemical effects could alter allergen conformation (Krishnamurthy et al, 2007) or cause protein aggregation (Chung et al 2008;Yang et al, 2010), resulting in the loss or modification of conformational epitopes. Furthermore, radicals may be induced during PUV treatment due to molecular ionization under its high-energy burst of lights.…”

“…In the study by Chung et al (2008), the solubility of Ara h 2 (18-20 kDa), the most potent allergenic peanut protein (Chu et al, 2008;Dodo et al, 2005) was unaffected, but in a separate study by Yang et al (2011) where raw peanut extracts, roasted peanut extracts and peanut butter slurry were treated with PUV under different conditions, Ara h 2 was significantly inactivated. Specifically on soybean, Yang et al (2010) noticed a pronounced reduction in soybean allergens (glycinin, 14-34 kDa and -conglycinin, 50 kDa), when PUV was applied to soybean protein extracts for a duration up to 6 min with 3 pulses per second. SDS-PAGE (Fig.…”

Quinoa (Chenopodium quinoa Willd.) versus soja (Glycine max [L.] Merr.) en la nutrición humana: revisión sobre las características agroecológicas, de composición y tecnológicas

“…La industria alimentaria también podría recurrir a procesamientos que no impliquen efectos térmicos a través de procesos con alta presión hidrostática, incidencia de luz UV o caída de presión controlada. Se han detectado reducciones de hasta un 44% en la capacidad enlazante de IgG y IgE en extractos de soja descascarillados y desengrasados 112,113 .…”

Gamma Rays’ Effect on Food Allergen Protein

“…Therefore, it is an attractive option to cause the breakdown of the possible allergenic structures naturally present in various foods [32][33][34][35].…”