Production of hoplike beverage bittering materials

Abstract

Abstract 2,4-DIACYL-5-ALKYL-4-HYDROXYCYCLOPENTANE-1,3-DIONES (TETRAHYDROISO-ALPHA ACIDS) (TETRAHYDROISOHUMULONES) R1, R2, and R3 are various alkyl groups which may or may not be identical, e.g., in the formulas above, if R2 R3 CH2CH2CH(CH3)2 isopentyl and R1 -CH2CH(CH3)2 isobutyl, the compound I becomes desoxytetrahydrohumulone 3'',5''-diisopentyl2'',4'',6''-trihydroxyisovalerophenone and III becomes tetrahydroisohumulone. Similarly, when R2 and R3 are isopentyl and R1 is -CH(CH3)CH2CH3 or -CH(CH3)2, the starting material (I) is respectively desoxytetrahydroadhumulone and desoxytetrahydrocohumulone, the intermediates II become tetrahydroadhumulone and tetrahydrocohumulone, and the end products III become tetrahydroisoadhumulone and tetrahydroisocohumulone. For clarity, it should be stated here that desoxytetrahydroalpha acids are herin designated by I and may also be designated a 3'',5''-dialkyl-2'',4'',6''-trihydroxyacylphenone, that the intermediate tetrahydrohumulone is herein designated by II and may also be designated a tetrahydro-alpha acid or a 6-acyl-2,4dialkyl-2-hydroxycyclohexane-1,3,5-trione, and that the ultimate end product, the tetrahydroisohumulone, is herein designated III and may sometimes be designated a tetrahydroiso-alpha acid or a 2,4-diacyl-5-alkyl-4-hydroxycyclopentane-1,3-dione. Moreover, sometimes the terms ''''alpha acids'''' and ''''iso-alpha acids'''' are employed herein without the ''''tetrahydro'''' prefix, without any intention, however, to define a different material when such abbreviation is employed. Such abbreviation, when employed, will be apparent to one skilled in the art. To conform with current nomenclature practice, lupulones are usually referred to herein as beta acids; tetrahydrohumulones (II) as tetrahydro-alpha acids; and tetrahydroisohumulones (III) as tetrahydroiso-alpha acids. It should be recognized, however, that the terms alpha acids, ''''beta acids,'''' and ''''iso-alpha acids'''' are used herein in a generic sense and are not meant to limit the various alkyl groups R1,R2, and R3 (Chart I) to groups found in naturallyoccurring substances, the present invention being equally applicable to synthetically derived materials. 6-ACYL-2,4-DIALKYL-2-HYDROXYCYCLOHEXANE-1,3,5-TRIONES (TETRAHYDROHUMULONES) (TETRAHYDRO-ALPHA ACIDS) 3'',5''-DIALKYL-2'',4'',6''-TRIHYDROXYACYLPHENONES (DESOXYTETRAHYDROALPHA ACIDS) Production of hoplike beverage bittering materials by the peracid oxidation of 3'',5''-dialkyl-2'',4'',6''trihydroxyacylphenones to 6-acyl-2,4-dialkyl-2hydroxycyclohexane-1,3,5-triones (tetrahydrohumulones or tetrahydro-alpha acids) and isomerization thereof to 2,4-diacyl5-alkyl-4-hydroxycyclopentane-1,3-diones (tetrahydroisohumulones or tetrahydroiso-alpha acids). CHART I: Conversion of beta acids into flavoring materials in the tetrahydro-alpha acids family

Inventors

• 👤 Leonard R Worden

Bibliographic Details