The Brazilian Federal Inspection Service prohibits the CO 2 addition to milk to cheesemaking and other dairy products. The justification against the addition of CO 2 is that the antimicrobiological effects reported in the current literature may generate negligence with regard to good manufacturing practices for milk and dairy products manufacturing. However, the main beneficial effects for various dairy products such as cheeses, are in terms of technological and economic aspects. These benefits generated by the use of CO 2 are sufficient to justify its applicability and encourage future research. As repor ted by dairies that worked with milk acidified by CO 2 injection to the cheese-making, only the savings with the reduction of coagulant use would be sufficient to ensure the return of investment in the injection system in just two and a half months . Therefore, it is believed, however, that the legislation on the CO 2 use can progress, particularly if there is interest by the dairy industry. The technological effects in milk caused by the use of CO 2 suggest the need for modification of the manufacturing process of some products to improve the benefits. Successful modifications are required to provide stimulation for the dairy industry to make the decision regarding to the use of this technology. This paper presents a review of the properties and effects of using CO 2 in milk and dairy products attempting to understand and increase the contribution of scientific knowledge about this technology by researchers and dairy companies in the Brazilian.