Process for the production of allergen-containing extracts

Claim 1

In a process for preparing an allergen extract which includes pre-extracting an allergen-containing material having a plurality of allergens, a portion of which is more lipophilic in character than the remainder, with a lipophilic solvent consisting essentially of an aqueous solution of a neutral, water-soluble cyclic ether having a boiling point below 105° C. which is at least one member selected from the group consisting of tetrahydrofuran, tetrahydropyran and dioxane to extract said lipophilic portion; extracting resultant allergen-containing material with a hydrophilic aqueous or aqueous alcoholic allergen solvent; and recovering water-soluble allergens from said material; the improvement which comprises: (a) separating undissolved solids from said pre-extraction step and concentrating the separated liquid phase at a temperature not exceeding 40° C.; (b) extracting said separated undissolved solids with said hydrophilic aqueous or aqueous alcoholic allergen solvent; and (c) combining the resultant extracts to form an allergen extract containing both hydrophilic and lipophilic portions.