An interesting research that sought to explore the link between rituals and food found that joyful singing of 'Happy Birthday' before having a slice of cake, adds to the taste of the cake.
Singing the birthday wish and blowing out candles actually uplifts the flavor of the food.
This perhaps explains why certain rituals are performed before eating and then the food appears all the more tasty. In some experiments carried out for this study, performing a ritual and extending the wait for the food seemed to add to the flavor and taste of food. This perhaps explains why some rituals are performed before meal times.
In the world of medicine too, researchers feel they could explore the idea of performing rituals before a surgery and then evaluate pain as well as healing, post surgery. This would be an interesting experiment into how the mind actually tricks the body with a placebo effect.