43. AVOIDING TEMPERATURE ABUSE
MODULE 4
AVOIDING
TEMPERATURE ABUSE
Time and temperature abuse is the most common food handling error that leads to foodborne illness. The objective of this module is to teach participants how to calibrate and use temperature measuring devices correctly. It also defines the important time and temperature combinations needed for safe cooking, cooling, reheating, and hot/cold holding of foods.

44. The “temperature danger zone”
The temperature danger zone is the range in which harmful (disease-causing) bacteria grow and may produce toxins.
The danger zone is officially between 41o oF.
Most bacteria grow best at human body temperature of 98.6oF This is why food handlers are a common source of foodborne disease organisms in food establishments.
While disease causing bacteria usually grow between 41o and 140o F, spoilage bacteria can grow over a wider temperature range. Spoilage microorganisms often grow at lower temperatures.

45. Three rules for temperature control
Keep potentially hazardous foods out of the temperature danger zone
Pass potentially hazardous foods through the danger zone as quickly as possible
Pass potentially hazardous foods through the danger zone as few times as possible
Rule one: Keep hot foods above 140o F and cold foods below 41o F
(Common phrase: keep it hot, keep it cold or don’t keep it!)
Rule two: Industry standards call for a 4-hour cooling period to bring food from 140o F to 41o F. The FDA Food Code proposes a 2 tier cooling curve whereby foods are cooled from 140o F to 70o F in less than 2 hours and from 70o F to 41o F in an additional 4 hours.
Rule three: Foods should only be reheated one time. If a food has not been served after it has been cooked, cooled and re-heated, it should be discarded.

46. Thawing In the refrigerator: less than 41o F
Under warm running water: less than 70o F (for less than 2 hours)
In the microwave oven: cook foods immediately after thawing
As part of the cooking process
NEVER thaw at room temperature!
There are four approved methods for thawing foods:
Thawing in the refrigerator (< 41o F) is best since food will not be exposed to the temperature danger zone. This method usually takes a long time to thaw food. Be sure to plan ahead.
Foods can also be thawed under warm (< 70o F) water usually recommended for less than 2 hours. This is a good method for thawing whole chickens or turkeys.
Some foods can be thawed in the microwave, but it is important to cook the food immediately after thawing.
Foods can also be thawed as part of the cooking process.
Foods should never be thawed at “room temperature” because this exposes foods to the temperature danger zone.
Proper thawing helps maintain food safety and food quality.

47. Cooking
Cook all potentially hazardous foods to minimum required temperatures
Measure the temperature at the thickest part of the food product (usually the center) with an accurate thermometer
Foods are cooked to make them more palatable to eat and to destroy harmful bacteria that may be present.
All potentially hazardous foods should be cooked to the appropriate safe temperature. Food temperature should be measured in the most central region of the food or its container.

48. Final cooking temperatures
Food Temperature Time
Beef Roast (rare) oF min.
Beef Roast (rare) oF min.
Eggs, Beef (other than oF sec.
Roasts), Fish
Ground Beef and oF sec.
Pork, Game Animals
Beef roast (medium), oF min.
Pork Roast, and Ham
Poultry, Stuffed Meats oF sec.
This slide lists safe cooking temperatures and times for various foods.
Poultry and stuffed meats require the highest cooking temperature and should be cooked to an internal temperature of at least 165o F for at least 15 seconds.
Ground beef and pork should be cooked to an internal temperature of at least 155o F for at least 15 seconds.
All other potentially hazardous foods (like fish) should be cooked to an internal temperature of at least 145o F for at least 15 seconds.

49. Microwave cooking
Heat foods at least 165o F because foods can heat unevenly
Rotate and stir during cooking
Cover food to retain moisture
Allow to stand covered for 2 minutes to evenly distribute the temperature
The distribution of heat is uneven in foods heated in the microwave oven. Some parts of the food are heated while others stay cold.
Because of uneven heating, ALL potentially hazardous foods if cooked in a microwave oven should be cooked to an internal temperature of 165o F or higher.
Heat can be evenly distributed in foods cooked in the microwave by rotating and stirring foods during cooking.

50. Cooling foods rapidly
Smaller portions: break larger food products down to smaller sizes
Shallow pans: no more than 2 inches deep for thick foods and no more than
3 inches deep for thinner foods
Ice bath: place containers of hot food into a sink or other container filled with ice
Improper holding of foods is the number one causative factor involved in foodborne illness. Improper cooling is a common mistake.
Reducing the size of the food item facilitates cooling.
Break down solid pieces of food (like beef roasts) to several smaller pieces. They will cool more rapidly.
Break down liquid foods into smaller containers or use shallow pans for cooling (product height should be less than 2 inches for viscous foods and less than 3 inches for less viscous foods).
Placing the food container in an ice bath will also facilitate cooling.

51. Cooling foods rapidly Stir food frequently to accelerate cooling
Remove lids of containers in coolers or on ice ONLY during cooling
Circulate cool water in steam kettles to rapidly remove heat from foods
Foods cool faster if they are stirred . This helps to remove heat from all areas of the food.
Foods and containers should be left uncovered during the cooling process. If a food is covered, the heat cannot easily escape.
Cold water can be circulated through steam-jacketed kettles to rapidly cool foods.
Combining cooling strategies expedites cooling. (i.e. stir soup while it is held in an ice bath).

52. Cooling times FDA Food Code recommendations:
A 2-tired cooling cycle (6 hours total time)
From F in less than 2 hours
From F in less than an additional hours
Industry standards:
From F in less than 4 hours
There are two recommendations for cooling of foods.
The FDA Food Code allows for a total of 6 hours during cooling in a 2-tiered cooling cycle. They recommend that foods be cooled from F (“super danger zone”) in less than 2 hours and then from 70–41F in less than 4 hours. Science has shown that this 2-tiered method keeps food safe and is sometimes more manageable for retail food establishments.
The Industry standard suggests cooling from F in less than 4 hours. This standard is usually more conservative and is often easier to remember.

53. Cooling rates for chili: ice bath vs. walk-in cooler
This graph illustrates the differences in cooling rates for two different cooling methods.
Note that the ice bath cools the chili almost twice as fast as simply placing the chili in a walk-in cooler. The chili is passed through the temperature danger zone in under two hours when cooled on ice. Even after eight hours, the chili cooled in the walk-in is still in the temperature danger zone.

54. Proper methods for reheating foods
Potentially hazardous foods must be re-heated to 165o F in 2 hours or less
Conventional stoves, ovens, steamers, and microwave ovens are approved for re-heating use
Crockpots and steam tables are NOT approved because they do not rapidly heat foods.
All potentially hazardous foods (that have been properly cooked, cooled, etc.) need to be reheated to at least 165o F in 2 hours or less.
The safe reheating temperature of 165o F applies to all foods that are reheated in an oven or steamer.
Generally, crockpots and other slow-cooking devices are not approved for reheating foods. They cannot rapidly heat foods.

55. Temperature measurement
Thermometers: digital or dial type with metal stem
Thermocouple: separate probe handle
Infrared thermometer
Liquid-filled thermometers (alcohol
or mercury) are NOT to be used
There are many different types of temperature measuring devices that can be used in food establishments.
The bi-metallic metal-stemmed thermometers are most common. Some will have a dial face and others may have an LCD digital display.
The sensing portion of a metal-stemmed thermometer is about one inch above the point on the stem.
A thermocouple can also be used. The sensing portion of a thermocouple is usually on the point of the stem.
Another type of thermometer is an infrared thermometer. They have a “trigger” that is used to measure surface temperatures of foods and packages. They are NOT accurate for measuring internal product temperatures.
Some thermometers cannot be used in food establishments (such as mercury or alcohol filled). Check to see that a temperature measuring device is approved for use before using it with foods.

56. Thermometer accuracy and calibration
All thermometers that are used to check food temperatures must be calibrated regularly to ensure accuracy
Only thermometers that are accurate and can be calibrated should be used
Thermometers should be properly calibrated to assure accuracy.
Thermometers can be calibrated by using an ice-water bath (calibrate to 32o F) or boiling water (calibrate to 212o F).
Thermometers should be periodically calibrated. (i.e. before first use, after being dropped, stored a long time without use, etc.).

57. Proper use of thermometers
The sensing portion of the thermometer must be clean and sanitized
The sensing portion of the thermometer must be positioned in the center-most region of the food product or container
Make certain the thermometer temperature has stabilized before taking a reading
When using a thermometer to measure temperature of a food, be sure that the thermometer stem is clean and sanitary. This will help prevent cross contamination.
The sensing portion of the thermometer should be positioned in the part of the food that heats up last. This is usually the geometrical center or thickest part of the food.
Metal-stemmed thermometers can take 10 to 15 seconds to accurately measure temperature. Thermocouples usually only take a few seconds.
Be sure that the thermometer temperature has time to stabilize before taking a reading.

58. Preventing cross-contamination
Clean the probe of the thermometer with a single-service towel or alcohol swab, or rinse in a sanitizing solution when transferring to different foods
Thermometers can also be sanitized by submerging in hot water (>180o F)
Clean and sanitize the probe when moving from raw to cooked or ready-to-eat foods
Don’t wipe probes on a soiled cloth or apron!
Just like any other utensil, a food thermometer can serve as a vehicle for cross-contamination.
When measuring food temperatures, be sure that the thermometer has been cleaned and sanitized before use.
Thermometers can be sanitized with an alcohol swab, a cleaning/sanitizing solution, or by dipping in hot water (>180o F).
DO THE TEMPERATURE ABUSE DEMONSTRATION ON THE NEXT SLIDE.

59. Thermometer calibration demonstration
This demonstration is intended to show food handlers how to calibrate and use temperature measuring devices. By showing the participants many different types of temperature measuring devices, they better understand the calibration and use can be different depending on the type of temperature measuring device used.
CONTINUE THE BACTERIAL GROWTH DEMONSTRATION