Rock Doc

Eighty years ago my mother was in grade school where schoolroom paste was made by mixing a little flour and water together. Memories of that simple glue came back to her when she and I recently stood in my kitchen, mixing two small batches of flour and water. First I mixed regular “better for bread” flour with water in a little dish, then I did the same with special test flour made from soft durum wheat. The first mixture was a pasty, lightest-of-light-tan color, the second had a pale but clearly evident yellow hue.

The simple experiment was inspired by the hardness of different types of wheat...