Water in Cooking

Water is the dominant molecule in nearly all foods — raw meat is ~75% water, fruits and vegetables up to 95%, human bodies ~60%. Its seemingly simple structure (two hydrogens, one oxygen) conceals unusual physical properties that govern almost every aspect of cooking: how food heats, how it freezes, why steam scalds, why salt preserves, and why oil and water won’t mix.

Hydrogen bonding: the master property

Oxygen pulls more strongly on shared electrons than hydrogen does, making water an electrically asymmetrical (polar) molecule — positive at the hydrogen end, negative at the oxygen end. This polarity creates hydrogen bonds: weak electrical attractions between the negative oxygen of one molecule and the positive hydrogen of another. In liquid water, each molecule participates in 1–4 hydrogen bonds at any moment, constantly forming and breaking.