Aging is a rest period to which almost all slaughtered animals and birds must be subjected in order to let their tissues soften. In fact, after slaughtering, the animals' muscles undergo a series of transformations which makes their meat hard, hence they have to acquire softness through this maturation process. Beef meat should hang for at least a couple of weeks in a dry environment and at a temperature not exceeding 3°C; for game the time can vary from 3 to 8 days. Domestic birds require much shorter times like 24-48 hours.