The present invention relates to a device, in particular a portable device, which may contain a liquid and a dehydrated substance, for example an edible substance, which can be mixed at a certain moment for rehydration. The device also includes means for using the rehydrated substance. The method consists in the device operation steps, so as to mix the substance and the liquid and at the same time prepare the means of use of the rehydrated liquid substance. The device and method are especially adapted for use during daily trips.
