The aim of this work is to study the effect of High Pressure Processing (HPP) on the allergenicity of the main protein involved in peach allergy (Pru p 3). Results obtained showed that most pressure/time combinations slightly enhanced in vitro IgE-binding to Pm p 3 and peach extract. Moreover, additional tests were carried out by means of skin prick tests on peach allergic patients. Different from in vitro results, in vivo effects evidenced that HPP (600 MPa/5 min) can either reduce or increase Pm p 3 allergenicity, depending on the particular sensitisation of each patient. Notwithstanding this variability, it is highly remarkable that the skin response to pressurized peach extract was stronger in more than half of individuals. These results would suggest a higher risk of HPP-treated peach products to elicit an allergenic reaction. However, it has been also proved that matrix plays an important role in peach allergenicity modification. Consequently, further investigations are needed before extrapolating results to more complex products. Industrial relevance: Peach allergy is one of the most frequent allergies in Mediterranean countries among adult patients. However, up to date, there is no information about the effect of HPP on peach allergenicity. This study increases understanding about the impact of processing on an important fruit allergen in order to advance knowledge-based ways to managing allergens risks in industry, as well as it opens new opportunities of research in other technologies or strategies in the attempt to reduce peach allergenicity. (C) 2016 Elsevier Ltd. All rights reserved.