More tips on preventing soups from curdling:
- Temper the milk before adding it to the soup by gradually adding small amounts of the hot liquid, warming the milk slowly; then add it to the soup.
- Add a little heavy cream to the soup to help prevent curdling.
- In milk-based soups, add acidic ingredients, such as tomatoes and lemon juice, to the milk mixture. Do not add the milk to the acidic ingredients.
- Make a thin flour and water paste to mix into the milk before adding acidic ingredients. Thickening the soup with a flour mixture keeps the soup from curdling so easily.
- Avoid using low-fat and skim milk. The more fat the milk contains the less chance of curdling.
- Heat milk to 194 degrees F. before adding it to the soup. Do not boil.
- Heat all cream based soups slowly over low heat.
- Salt should be added just before the soup is ready to serve.