An ancient Chinese manual states that if the cook offers a meal without a harmony of the six flavors and the three qualities, it cannot be said that he serves the community.
Zen Master Dogen tells us that when washing rice, we should remove any sand that we find, and in so doing, we should not lose even one grain of rice. "When you look at the rice, see the sand at the same time. When you look at the sand, see also the rice. Examine both carefully. Then, a meal containing the six flavors and three qualities will come together naturally."