Meat

Meat is three tissues woven together: muscle fibers (the protein), connective tissue (the structural harness), and fat (the lubricant). Understanding how each responds to heat — they don’t agree — is the key to cooking any piece of meat well. Lean meat is ~75% water, ~20% protein, and ~3% fat. Everything that happens during cooking is a conversation between these components.

Muscle fibers

Individual fibers are hair-thin (0.01–0.1 mm diameter) and can extend the entire length of a muscle. They’re organized into bundles (fascicles) — the “grain” you see in cooked meat. Cutting across the grain severs fiber bundles short, making the meat easier to chew.