dairyforall.com says: Toned Milk Also called single toned milk, refers to milk obtained by the addition of water and skim milk powder to whole milk. In practice, w
…hole milk from buffalo is mixed with reconstituted spray dried skim milk for the production of toned milk. In India, as per PFA Rules (1976), the toned milk should contain a minimum of 3.0 per cent fat and 8.5 per cent solids not fat. Double Toned Milk Refers to milk obtained by the addition of water and skim milk powder to whole milk. Usually buffalo whole milk is mixed with reconstituted spray dried skim milk. In India, as per PFA Rules (1976), the double toned milk should contain a minimum of 1.5 per cent fat and 9.0 per cent solids not fat. Other sites say that dry low-fat skim milk is added to reduce the fat content but maintain the total milk solids. Ultra pasteurisation typically involves temps of 140C for 2 seconds but does not allow long shelf life without refrigeration, while the UHT described below could be even higher and for a longer period. The Amul Dairy site says: Amul Taaza is Long Life double toned milk. It is fresh and only fresh milk, which has been processed with a technology called UHT (Ultra High Temperature), hence also known as UHT milk. Notwithstanding popular misconception, UHT technology does not involve any use of preservatives. The UHT treatment ensures zero microbial activation, while preserving the maximum flavour, taste, and nutritional value. The aseptic packaging system protects the product from air and light and guarantees a long shelf life of 180 days without refrigeration. (MORE) 
