Generally speaking, food in dream usually refers to food for thoughts, ideas, new beliefs, etc. They are ideas you take in and digest mentally.
To see grains of rice in your dream, symbolizes success, prosperity, luck, fertility and warm friendships.
To dream that you are eating rice, denotes happiness and tranquility in the home.
To dream that you are cooking rice, signifies that new responsibilities will bring you much joy.
To see rice mixed with dirt in your dream, signifies illness and separation from friends.
courtesy of Dreammoods.com