Buttermilk is primarily due to lactic acid produced by lactic acid bacteria while fermenting lactose, the primary sugar in milk. As the bacteria produce lactic acid, the pH of the milk decreases and casein, the primary milk protein, precipitates, causing the curdling or clabbering of milk. This process makes buttermilk thicker than plain milk. While both traditional and cultured buttermilk contain lactic acid, traditional buttermilk tends to be less viscous, whereas cultured buttermilk is more viscous. Buttermilk can be drunk straight, and it can also be used in cooking. Soda bread is a bread in which the acid in buttermilk reacts
Crempog The mixture is meant to stand for a few hours. A second mixture is made using sugar, bicarbonate of soda, vinegar and beaten eggs. The mixtures are then combined to make a smooth, dense batter. The batter is poured onto a hot bakestone or griddle, over a moderate heat. The "crempog" is cooked until golden on both sides and served in a stack with butter spread on each pancake. In Anglesey and Caernarfonshire "crempogau" were prepared as "crempog furum", a pancake made with yeast, or "crempug wen" where the normally coarse flour was replaced with refined flour. These pancakes were