Sit in meditative pose and relax the whole body. Try to 'drink' air through the mouth and draw it into the stomach, not the lungs. Expand the stomach as much as possible, hold the air inside for a short period of time and then expel it by belching. Repeat the process.
This practice rejuvenates the oesophagus walls and the glands that secrete the digestive juices. It tones up the whole stomach and helps to eliminate disorders of the digestive system.