Acids and bases in cooking
Intermediate Kitchen science
Acids like lemon, vinegar and tomato, and bases like baking soda, change food's color, texture, browning and flavor, not just its taste.
Written with AI help from the sources listed, and published by Cory. Spot a mistake? Tell us and we'll fix it.
How do you do it?
- Finish rich or flat dishes with a squeeze of lemon or a splash of vinegar to brighten them.
- Add tomatoes, wine or vinegar to beans after they soften; acid keeps beans firm and slows cooking.
- Dress green vegetables right before serving; acid turns bright green chlorophyll olive drab within minutes.
- A pinch of baking soda softens beans and speeds onion browning, but too much makes food mushy and soapy-tasting.
Why does it work?
Acidity is measured on the pH scale: low numbers are acidic, 7 is neutral, higher numbers are basic. Acids firm up pectin, the glue holding plant cell walls together, so vegetables and beans stay firm, while bases break pectin down and soften them. Acid also knocks the magnesium out of chlorophyll, which turns greens drab. Acid unfolds proteins, which is why marinades firm the surface of meat and fish, and why too long in one leaves it mushy or chalky. Bases speed the browning reactions, while acid slows them. On the tongue, sourness brightens flavor and cuts through fat and sweetness.
What are the common mistakes?
- Simmering beans in tomato sauce from the start — they can stay hard for hours.
- Adding lots of soda to keep greens green — mushy texture, soapy taste, fewer vitamins.
Still stuck? Watch someone do it on YouTube.
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