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
National Loaf National Loaf The National Loaf was a bread made from wholemeal flour with added calcium and vitamins, introduced in Britain during the Second World War. Introduced in 1942, the loaf (similar to today's brown bread) was made from wholemeal flour to combat wartime shortages of white flour. The loaf was abolished in October 1956. The National Loaf was grey, mushy and unappetising; only one person in seven preferred it to white bread, which became unavailable. The government insisted on it because it saved space in shipping food to Britain and allowed it to better utilize its existing stock of wheat.