Autoclaving treatments applied to peanuts to reduce final immunoreactivity

Scope Peanut allergy is one of the most frequent allergies especially affecting developed countries. In order to reduce the risk of eliciting undesired reactions, a number of technological approaches have been devised to inhibit/remove allergens in order to deliver a hypoallergenic food. In the present work we investigated alternative strategies based on thermal treatments like autoclaving to decrease peanut immunogenicity. Methods Raw and autoclaved peanuts were extracted, separated on SDS-PAGE and further submitted to immunblot analysis using sera of allergic patients. Each individual extract was further analysed by ELISA in order to estimate the residual immunoreactivity of the processed peanuts. The most resistant allergenic proteins displayed in the gel were finally identified by LC-HRMS analyses. Results A progressive reduction in the intensity of the major allergenic bands was highlighted in autoclaved samples; such behaviour was even more evidenced with a total disappearance of the major allergenic proteins when samples were preliminary exposed to hydration. These data also confirmed results obtained by ELISA analysis. Raw and treated peanut material were finally submitted to Western blot analysis in order to assess the residual immunogenicity of the treated peanuts. Conclusion Hydrating peanut seeds prior to autoclaving increased the efficacy of the thermal treatment contributing to the disappearance of the main allergenic proteins and reducing significantly the final immunoreactivity, as assessed by ELISA tests and immunoblot analysis.