Dairies process milk and make or supply a range of dairy products for households, retailers, caterers and food manufacturers. Their work may include collecting milk from farms, cooling and testing it, pasteurising or otherwise treating it, and bottling it for sale. Products can include whole, semi-skimmed and skimmed milk, cream, butter, yoghurt and other cultured dairy foods. Some businesses also arrange delivery of milk and related products to homes or commercial customers. Cheese makers turn milk into cheese through processes such as adding cultures and rennet, separating curds from whey, pressing, salting and, for some varieties, ageing the cheese under controlled conditions. They may produce fresh, soft, semi-hard or hard cheeses, including varieties made from cow's, goat's or sheep's milk. Services can include supplying cheese in retail or catering quantities, cutting and packing products, and making batches to particular specifications.