If the food is earned through unrighteousness means, it will generate wicked feelings.

Satwik food must be less spicy, less salty and must have less amount of tamarind (sourness). Not merely that, it must not be made up of excess oil, must be fresh and must not be stale (food prepared in the morning should not be taken in the evening). This isSatwik food. Some people consider milk as Satwik. No doubt, milk, curds and fruits are Satwik in nature, but when consumed in excessive amounts, they become Tamasik and make one dull and sleepy. When we take curds in excess, we can become Tamasik. Hence reduce having milk or curds in large quantities. It is good to mix one part of water with one part of milk. The food you eat must have been earned and prepared through the right means and should be offered to God before partaking. Only then Satwikfeelings will emanate in man. If the food is earned through unrighteousness means, it will generate wicked feelings.

Bagavan Sri Sri Sri Sathya Sai Baba