The invention relates to a process for the preparation of a freeze-dried fruit of Parkia, preferably Parkia speciosa comprising the steps of a) freezing a fruit, preferably beans from Parkia to -20°C or below to obtain a frozen fruit and b) subsequently freeze-drying the frozen fruit by reducing the pressure surrounding the said frozen fruit to allow water and volatiles to sublimate and/or evaporate from the frozen fruit to obtain the freeze- dried fruit of Parkia, wherein the temperature of the fruit during freeze-drying is at most 0°C, wherein the temperature of the fruit from the beginning of step a) until the end of step b) does not exceed 30°C, preferably does not exceed 25°C, preferably does not exceed 20°C, more preferably does not exceed 10°C, for example does not exceed 4°C, for example does not exceed 0°C. The invention also relates to the product obtained with said process, a pharmaceutical composition comprising said product, a nutraceutical composition comprising said product, said pharmaceutical composition for use as a medicament, preferably for use in the treatment, co-treatment and/or prevention of diabetes mellitus, to a method of treatment, co-treatment or prevention of diabetes mellitus in animals using said product or said composition and to use of said product or said composition for weight regulation.Linvention concerne un procédé de préparation dun fruit lyophilisé de Parkia, de préférence de Parkia speciosa comprenant les étapes qui consistent : a) à congeler un fruit, de préférence des haricots de Parkia à -20°C ou moins pour obtenir un fruit congelé, et b) à lyophiliser ensuite le fruit congelé par réduction de la pression autour ce dernier pour permettre la sublimation et/ou lévaporation de leau et/ou de substances volatiles dudit fruit congelé afin dobtenir un fruit lyophilisé de Parkia. La température du fruit pendant la lyophilisation est au plus de 0°C, et la température du fruit pendant la lyophilisation depuis le début de létape a)
