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Published on: June 20, 2019
Factors influencing the formation of medicinal off-flavor from ascorbic acid and α,β-unsaturated aldehydes
Kensuke Sakamaki1, Susumu Ishizaki, Yasutaka Ohkubo
1Technical 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
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.
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