Glucovanillin and vanillin contents of vanilla beans at different stages of the curing process. a, green vanilla beans; b, freshly blanched vanilla beans; c, sweating vanilla beans; d, drying vanilla beans; e, cured vanilla beans; CGP, content of glucovanillin in the placental area as the dry weight of the placental area; CGF, content of glucovanillin in the fleshy area as the dry weight of the fleshy area; CV, content of vanillin as the dry weight of the total vanilla bean.