One evening, Dogen instructed,

At a Zen monastery in China sometimes they sift the wheat and rice, etc, throwing away the bad grains and keeping the good ones to cook. A certain Zen master admonished in a verse, “Though you split my head into seven pieces, do not winnow the rice.” What he meant was that monks shouldn’t fuss about arranging fine meals, rather they should eat whatever is available. When it is fine they should eat it as it is, and when it is poor, they should eat it without dislike. Get rid of your hunger and support your life with the faithful donations from patrons or pure food from temple belongings alone and devote yourself to the practice of the Way. Do not choose good from bad on the basis of taste. Now each of you in my assembly should also have this attitude. (Shobogenzo Zuimonki, Book 2, Chapter 21)