The pantry in our place on Willow Creek has an eight-foot shelf devoted to nothing but flours: bread flour, whole wheat, soft white biscuit flour, semolina for pasta, you name it. My capable wife has a wonderful way with dough, and I myself can turn out a pretty good stack of sourdough pancakes. Wheat holds pride of place in our culinary life, as on our family farm, and it seems not just bountiful but also wholly beneficent. Or so I thought, until I worked up the chapter on wheat for the Oxford