Starting and Keeping a Sourdough Starter

Mix 50 g of wholemeal rye or wheat flour with 50 g of lukewarm water in a jar, cover it loosely, and leave it at room temperature. Every 24 hours, throw out all but 50 g and feed it 50 g flour and 50 g water. Around day four it may go quiet after a burst of bubbles; keep feeding. By day seven to ten it should double within six to eight hours of a feed and smell pleasantly sour. That's when it can raise bread. Between bakes, keep it in the fridge and feed it once a week.