Buttermilk and kefir

Buttermilk and kefir: Kefir is a cultured product. Milk for kefir is thickened in the process
of ultrafiltration thanks to which it is rich in proteins, especially in albumins and globulins.
Kefir enhances metabolism and the body's assimilation of milk components; it is also
a rich source of vitamins. Buttermilk is also a cultured beverage of high nutritional value.