A method for the production of a purified extract of natural allergens comprising the steps ofa) extracting a natural source of allergens comprising allergenic proteins to form an extract,b) purifying of said extract to remove non-protein components to form a purified extractc) denaturating said purified extract to form a purified denaturated extract, said purified denaturated extract comprising proteins, wherein the most abundant (w/w) proteins, forming together at least 60% (w/w) of all proteins, are at least two proteins, and all proteins represent at least 60% (w/w) of the dry weight of the purified denaturated extractanda method for the production of a purified extract of natural allergens comprising the steps ofa) hydrolysing a denaturated allergen to form an allergen hydrolysate,b) purifying said allergen hydrolysate to remove peptides with a molecular weight above 10,000 Da and below 1,000 Da in order to obtain a purified hydrolysate where 70%, more preferably 80% of the peptides are between 10,000 Da and 1,000 Da.