The Problem With Cooling Food

Is There a Problem?

Improperly cooled food is a leading cause of foodborne illness. Why is that statement true? If food is cooled in a refrigerator and reheated thoroughly, shouldn't it be safe? The truth is cooked food may not be free of bacteria or can be recontaminated. If food cools too slowly, bacteria can grow to harmful levels. If the reheat process is not done correctly, these bacteria will cause illness. Some types of bacteria produce toxins which will not be destroyed even by proper reheating procedures. These toxins will also cause illness. People generally understand the importance of cooling food by placing it in the refrigerator, but the proper cooling of food can be a more difficult procedure than we think.

A Look at Cooking

To understand why cooling food can be difficult, let's first examine some cooking procedures. When food is cooked it is done with heat much greater than the final cooking temperature of the food. For example, to cook a lasagna to reach an internal temperature of 165°F an oven may be set at 350°F, a difference of 185°F. Stove tops and fryers are even hotter. When cooking food, processes such as stirring and flipping may occur which results in quicker cooking as heat is distributed throughout the food. Much attention is given to cooking food to make sure it is done right and not ruined.

Cooling Versus Cooking

The equipment used to cool food is not as effective as the tools for cooking. Compare the cooking processes to the cooling procedure. Cooling food to 41°F is usually done in a refrigerator that maintains a temperature of 41°F. or less. Even if an ice bath is used (32°F), the difference between the desired food temperature of 41°F and the cooling source is just a few degrees. Additionally, food that is cooling is usually placed into a refrigerator where it receives little attention until it is needed. Some may argue that their refrigerators cool food fast enough, but if the food is stored in deep containers or not sliced thin, food can take more than 1 day to cool to the proper temperature. Cooling food properly is the most crucial and difficult procedure to control.

What Can Be Done?

Food - ice bathUse of an ice bath and an ice wand.Current food code requires food to cool to 70°F within 2 hours, then from 70 to 41°F within 4 more hours. How can this be done? Quick-chill methods are the accepted practices for cooling food quickly. Ice bathing food, use of ice wands, or storing food in shallow layers are a few of the methods that will facilitate quicker cooling of food. Ice bathing is a process where a stock pot of hot food is placed into ice water. Ice wands are filled with water, frozen, then used to place into hot food. Combining these methods, ice bathing while stirring food with an ice wand, provides very effective cooling for soups and sauces. When cooling in the walk-in cooler, keep food containers shallow and uncovered in the coldest part of the cooler, where there is good air circulation. Use of metal pans is recommended to transfer cold to the food. Food should never be placed in a reach-in or preparation refrigerator to cool. This equipment is designed only to hold cold food cold, not to cool hot food. During the cooling process, stirring or rotating food also quickens food cooling. Contact your area sanitarian and schedule a meeting or an in-service to further explain these methods and evaluate your current procedures.

Out of Sight, Out of Mind - Not

Because cooling food is generally an out of sight, out of mind process, using a time/temperature log will help to keep employees and yourself aware that food is in the cooling process. Log forms are a useful tool and can be utilized for cooling foods as well as other food items (hot holding, cold holding, storage) and refrigerators. You can print out a log form by clicking on the link found at the bottom this page. These logs will allow you to chart the effectiveness of your cooling procedures and if needed to make changes to keep your food safe.

Temperature Log (pdf)

Temperature Log - Landscape Version (pdf)