Allergenic proteins in wine: an overview of results obtained from proficiency-tests

Abstract

Food allergy is a significant health problem, and food industry is obliged to provide accurate labelling by clearly indicating the presence of some allergens to protect consumers. This issue concerns also winemakers as the EU Commission Implementing Regulation No. 579/2012 of 29 June 2012 establishes that wines treated with allergenic additives or processing aids are subject to specific labelling if their presence can be detected in the final product. The request of analyses of allergens in wines has increased in recent years, and laboratories therefore have a key role to play in this process. The most performed method for detection and quantification of proteins in wine is the ELISA method, thanks to its performances, ease to use and relatively moderate costs of equipment. However, the analysis of allergens in wine remains a challenge for laboratories, which can choose from an increasing number of kits that differ in allergen extraction method and are likely to estimate diverse forms of the researched protein. To allow laboratories to compare their results and to obtain recognition of their analytical procedures by winemakers and accreditation bodies according to the ISO/IEC 17025 standard, regular proficiency-testing schemes (PTS) for the detection and quantification of allergenic proteins in wine have been proposed since June 2014. For each test, the statistical treatment of the laboratories’ results is performed according to ISO 13528. Results obtained in different tests for analyses of casein, ovalbumin and lysozyme on red, white and rosé wines show that these analyses are well managed by laboratories, even if some drawbacks are encountered especially for some matrices whose physico-chemical properties can interact with the searched allergen.