The crisp weather of fall, along with end of season garden produce, can result in a delicious large kettle of homemade soup. Reheated, soup makes a convenient lunch or evening meal. It is easy and economical to make healthy soups by controlling the fat and sodium content.
Preparing a large batch of soup can present a food-safety challenge – cooling. One of the leading causes of foodborne illness is the failure to properly cool foods.
The food danger zone is that place between 41 degrees and 140 degrees F, where bacteria grow most quickly. The USDA states that it would take an 8-inch stock pot of hot chicken soup 24 hours to cool to a safe temperature in your refrigerator. Soup must cool from 140 degrees to 70 degrees F in two hours and from 70 degrees to 40 degrees F in no more than four hours.
To rapidly cool soup safely, follow these guidelines:
Use an ice water bath. An ice water bath helps decrease the soup temperature quickly and safely. Begin with filling a large container or clean sink with ice and a small amount of water. Place the kettle of soup into the ice bath and stir the soup to release heat and aid cooling.
Use shallow pans. The smaller the portions, the quicker the cool down. Divide a large batch of soup into small containers, no deeper than three inches. Stir occasionally to aid cooling. Select stainless pans which transfer heat away from food faster than plastic.
Use ice in the recipe. You can reduce cooling time by adapting your soup recipe. Prepare a thicker soup reducing the original amount of water or liquid called for in the recipe, then add ice to the soup at the final preparation step.
Use cooling paddles. These are more commonly used in a commercial kitchen. The plastic paddle is filled with ice or water and then frozen. Soups stirred with these paddles will cool quickly.
A large container of hot soup should not go directly into the refrigerator. It may take too long to cool and can raise the internal temperature of your refrigerator.
When making a large batch of soup, plan ahead for the cooling method you plan to use. Begin your plan by having an accurate food thermometer to keep tabs on the temperature during the cooling process.