title: Factors influencing the formation of medicinal off-flavor from ascorbic acid and α,β-unsaturated aldehydes.
abstract: In a previous study, the formation and formation pathway of 6-propylbenzofuran-7-ol as an off-flavor compound formed from ascorbic acid and (E)-hex-2-enal in a test apple beverage were investigated. In the present study, elucidating the pH, temperature, and (E)-hex-2-enal and ascorbic acid concentrations that lead to the generation of 6-propylbenzofuran-7-ol in various model solutions was performed. The quantities of 6-propylbenzofuran-7-ol generated in model solutions increased when the initial concentrations of (E)-hex-2-enal and ascorbic acid increased, and linear correlations between the quantities and concentrations were observed. The quantity of 6-propylbenzofuran-7-ol steadily rose in step with pH from pH 2.24, peaked at pH 3.73, and steadily decreased in step with pH to pH 4.24. The quantity of 6-propylbenzofuran-7-ol increased sharply as the storage temperature rose. Meanwhile, no 6-propylbenzofuran-7-ol was produced when short-duration heating processes such as heat sterilization were applied. These results will allow to us prevent the occurrence of off-flavor by regulating the initial pH, storage temperature, and (E)-hex-2-enal and ascorbic acid concentrations. Reactions with ascorbic acid and other α,β-unsaturated aldehydes were also investigated, and it was confirmed that corresponding 6-alkylbenzofuran-7-ols were formed.
authors.affiliation: Technical Research Institute R&D Center, T. Hasegawa Co., Ltd., 29-7, Kariyado, Nakahara-ku, Kawasaki-shi, 211-0022, Japan. kensuke_sakamaki@t-hasegawa.co.jp
authors.forename: Kensuke
authors.initials: K
authors.lastname: Sakamaki
authors.forename: Susumu
authors.initials: S
authors.lastname: Ishizaki
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Ohkubo
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Fujimoto
authors.forename: Akira
authors.initials: A
authors.lastname: Fujita
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D001205:Ascorbic Acid / Q000737:chemistry*; D001572:Benzofurans / Q000032:analysis / Q000737:chemistry*; D001628:Beverages / Q000032:analysis; D005511:Food Handling / Q000379:methods; D005638:Fruit; D006801:Humans; D006863:Hydrogen-Ion Concentration; D027845:Malus; D009812:Odorants / Q000032:analysis; D012996:Solutions; D013649:Taste; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: D000447:Aldehydes; D001572:Benzofurans; D012996:Solutions; D014867:Water; D001205:Ascorbic Acid