Breakfast has an internal structure.

Crack an egg into a clear bowl and pause before turning it into breakfast. The yolk sits in a pool of white, but it is not simply floating loose. Near it you may see two twisted, pale cords. These are the chalazae: strands of egg white that help hold the yolk near the centre. A familiar ingredient suddenly starts to look less like a blob and more like an assembly.

The shell is mainly calcium carbonate. Beneath it sit two membranes; within those is the albumen, or egg white, surrounding the yolk. After the egg is laid, its contents cool and contract, and an air cell forms between the membranes, usually at the broader end. A chicken egg is a biological container with different materials doing different jobs. Hardness, flexibility, water and suspension are arranged in the same compact object.

The names are useful because they separate things that a recipe often treats as one ingredient. You can notice the shape of the air space, the thickness of the white and the anchoring cords without becoming a specialist. This is a way of looking rather than a cooking technique or a freshness test. An egg's appearance alone cannot establish that it is safe to eat. The small exercise is simply to replace the word 'egg' with a more attentive description. Much of the kitchen rewards this shift: what seems ordinary becomes interesting when you ask which parts are doing the work.