Some foods grow bacteria more easily and quickly than other foods. These foods are known as time/temperature control for safety (TCS) foods because they require certain time and temperature controls to prevent unsafe bacteria growth. These foods are sometimes called potentially hazardous foods (PHFs) because they become hazardous if their bacteria growth is not controlled.
Recognizing TCS foods and knowing how to properly handle them is an important factor of food safety. This article walks through all the basics of TCS foods to help you learn more about them and know how to keep your customers or guests safe.
What Qualifies as a TCS Food?
Some foods are more vulnerable to pathogen growth than others. TCS foods are foods that:
Have high carbohydrate and protein levels
Are neutral or slightly acidic
Most Common TCS Foods
The most common TCS foods include:
Fish and shellfish
Cream or custard
Cut leafy greens
Cut garlic in oil
Sliced melons and tomatoes
Why TCS Foods Can Be Dangerous
Bacteria need just three things to grow: food, moisture, and warmth. Small amounts of bacteria growth in TCS food are not a problem, but too much can cause foodborne illness. TCS foods have the nutrients and moisture bacteria need to grow. Add time and warmth to the mix, and these foods can become bacteria breeding grounds.
Time is an important part of bacteria growth. When bacteria have food, warmth, and moisture, their numbers can double every twenty minutes. After four hours, most TCS foods will have a high enough bacteria count that they become dangerous to eat.
The temperature of TCS foods can also encourage bacteria growth. The temperature range between 41° and 135° Fahrenheit creates conditions for rapid bacteria growth. This temperature range is so well suited for bacteria that it’s called the temperature danger zone. TCS foods in the temperature danger zone will grow bacteria quickly and can easily become hazardous.
How to Keep TCS Foods Safe
TCS foods can be kept safe by minimizing the time they spend in the temperature danger zone (41–135° F). When food is in the temperature danger zone, pathogens grow and multiply at a fast rate and can make food unsafe to eat.
In restaurant service, the two most common ways of controlling pathogen growth are time and temperature controls.
TCS foods that are ready-to-eat can be safely consumed in a four hour window. If they have not been temperature controlled, they should be discarded after four hours. Hot held and cold held foods can be served for four hours without temperature controls if they are discarded after the four-hour time limit.
Cold foods can be served for six hours as long as the food temperature stays below 70° Fahrenheit. Discard cold food that warm to over 70° Fahrenheit. If you do not regularly check the temperature of cold food that is not temperature controlled, you should throw it away after four hours.
To prevent dangerous growth, TCS foods are kept out of the temperature danger zone or moved through it quickly. Food temperatures are controlled with freezing, refrigeration, or holding. Food is refrigerated or frozen until it is prepared for service. If needed, cooked TCS foods can be safely cooled for later use by using the two-step cooling method. Ready-to-eat TCS dishes can be hot held above 135° or cold held below 41° Fahrenheit.
There are times when TCS foods will pass through the temperature danger zone, such as heating and cooling. In order to keep foods safe, do your best to minimize the time food spends in the temperature danger zone.
When cooling foods, the FDA Food Code recommends a two-stage cooling process. First, the food should be cooled from 135° to 70° degrees Fahrenheit in two hours or less. Second, the food should be cooled from 70° to 40° Fahrenheit in four hours or less. Total cooling should not exceed six hours.
Large batches of food, such as a large pot of stew, should not be cooled in one large container in a refrigerator. Doing so does not allow the food to cool fast enough and keeps the food in the temperature danger zone for too long and allows pathogens to grow to an unsafe level.
An inexpensive way to properly cool large batches of food is to divide it into smaller containers. Keep the containers uncovered while cooling to prevent extra moisture, but be sure to cover it when it has finished cooling.
When reheating foods that will be hot held, the food should be heated to 165° Fahrenheit or higher. Foods should reach 165° F in two hours or less. Because foods must be reheated in a quick manner, it is important to use appropriate cooking or rethermalizing equipment such as a microwave, stove, or oven. Do not attempt to reheat food for hot holding in warming trays or other hot-holding equipment because these devices will not warm up the food fast enough and will allow pathogens to grow.
These methods of time and temperature control effectively prevent bacteria growth. With good controls, bacteria growth can be limited and TCS foods kept safe.
Download Image: TCS Foods Poster
Editor’s note: This post was originally published in October, 2016 and has been updated for freshness, accuracy, and comprehensiveness.