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
Pan loaf top and bottom. Pan loaf A pan loaf is a style of bread loaf baked in a pan or tin. It is the most common style available in the United Kingdom, though the term itself is predominantly Scottish and Northern Irish so as to differentiate it from the plain loaf. It was once more expensive than the then more common plain loaf. Hence, to speak with a "pan loafy" voice is to speak in a posh or affected manner. The pan loaf has a soft pale brown crust all round the bread, in contrast to a plain loaf's darker crust