This comparative study is designed to compare the gastric layering and rates of emptying and by inference rates of digestion of two food emulsions. Two types of dairy based foods will be used, one which will sediment in the stomach and one that will not. On each of two study days, a total of 9 post drink MRI scans will be taken to assess gastric layering and emptying. Cannulation will allow blood samples to be taken periodically for subsequent analysis for the presence of specific digestion related hormones. A total volume of 36 ml of blood will be removed and volunteers will also be asked to complete a questionnaire at predetermined times to assess feelings of satiation.