Abstract
Foods that contain pro and pre-biotic denominate symbiotic, these benefit the health maintaining the balance from the intestinal flora, reducing to the bad absorption of the lactose, increasing the protection against intestinal infections, among others. The probiotic and pre-biotic are functional products and nutraceutics, first they are defined as "alive micro organisms with capacity to improve the intestinal microbial balance producing beneficial effects for the health of the individual" and the pre-biotic are non digestible nutritional ingredients and that selectively favour the growth of beneficial bacteria. The nourishing ingredients that fulfil the requirements of pre biotic, until the moment, are the oligosaccharides ones. Pro biotic bacteria present/display sites of different action in the digestive system (Lactobacillus acts in the thin intestine, whereas bifid bacteria acts in the heavy intestine). The re-introduction of these microbial groups in the lodging is done by means of the administration of selected species, which will have to be in high and viable numbers at the moment of their consumption. Some technical aspects are common in the production of any type of milk or fermented drink, as they are: (i) type of organisms that constitute the culture to starter, (ii) temperature, oxygen presence and period of incubation, (iii) the proportion of inoculo, (IV) the production of starter, and, (v) the growth factors.