The Cold Hard Facts about Cooling Food
Teaching Activities for the Classroom Setting or Onsite Inspection
Background
According to the Centers for Disease Control,
improper cooling is
one of the major
causes of foodborne
illness. Leaving
food in the
temperature danger
zone of 41°F to 140°F is a dangerous practice.
However, bacteria can grow and multiply every
10 minutes in the “super danger zone” between
70°F to 130°F making cooling food quickly an
important ingredient in preventing a foodborne
illness.
Discussion Items
Classroom or Onsite Inspection
Ask: What is the room temperature of this
room? Is this temperature within the danger
zone? Have you seen food cooled at room
temperature?
Onsite Activity
Have an employee check some food
temperatures that are cooling or were cooled
and are now in the cooler. Decide if any are in
the danger zone. Discuss proper cooling
methods.
Classroom Activity
Show a variety of thermometers available.
Explain that you
may need a variety
of types depending
on its use, i.e.
immersion probes
for deep pots of soup or chili, meat
thermometers, instant read, surface
thermometer, etc.
Classroom or Onsite Discussion
Discuss the 4 hour rule:
! It takes bacteria four hours to adapt to its
environment.
• Explain that the accumulated time cannot
exceed four hours. Discuss how time
accumulates when food is temperature
abused during the flow of food from
receiving through cooking. Once food has
been cooked, time will accumulate again
during holding, cooling, and reheating.
Review Procedures for Cooling Food
Classroom or Onsite Discussion
Why is cooling foods quickly a challenge? The
equipment we use to cool food is not as
efficient as the equipment we use for cooking.
Food is usually cooked with much greater heat
than the final internal temperature. For
example, to cook lasagna to reach an internal
temperature of 165°F, the oven temperature is
set at 350°F, a difference of 185°F. Fryers are
even hotter.
When we cool food, the difference of the ice
bath at 32°F and the desired food temperature
of 41°F are just a few degrees. If you cool food
in the walk-in cooler, the difference is
narrowed. That’s why it’s so critical to monitor
food during the cool-down process.
Onsite Discussion
" Ask for food items that are
routinely cooled in their
establishments.
" Ask how each food is cooled down
to meet the cooling temperature
requirements.
Teaching Activities for the Classroom Setting or Onsite Inspection
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" Ask to see their Standard Operating
Procedures (SOPs) or instructions for
cooling food. Remediate as necessary.
Classroom Activity
Divide participants in groups of 3 or 4. Have
them count off 1-3 or 1-4 so participants are
from a variety of establishments/settings. Ask
each person to write down a food that is
routinely cooled in their work place. Have
each person discuss the way the food is
cooled. Allow 5 minutes.
Bring the group back together. Have a few
folks share how foods are cooled.
Reinforce best practices in cooling food such
as:
" Factors that hinder the cooling process.
Foods high in fats and starches tend to cool
slowly. A dense film forms at the wall or
the containers and the surface of food
creates a barrier—that’s why it’s important
to stir the food.
" Discuss pan size, shape,
material it’s made from,
etc. Food cools faster
in thin-walled metal
containers than through
thick-walled glass or
plastic materials which
acts like an insulator and holds in heat.
" The smaller the surface of the container, the
faster the cooling process. Place foods in
shallow pans. The pan should be no more
than 6 inches high and the food depth no
more than 2-3 inches deep. During the cooldown phase, keep food uncovered or
loosely covered to allow heat to escape.
" Place uncovered food
on the top shelf of a
refrigerator to cool
quickly. Then cover
when cooled to 41°F.
Cooling time will be
increased by 10% if food is covered.
(Cover loosely if top shelf isn’t available to
avoid contaminating the product.)
" Reduce food mass—the smaller the
portions, the quicker the cool down time.
Cut solid foods like ham, roasts, turkey into
5 pounds or less.
" Remind them to use a
thermometer to monitor
the cooling process.
" Discuss the cooling
time/temperature
requirements—from
140°F or hot to 70°F with
2 hours; then from 70°F to
41°F with 4 more hours.
" Salads made at room temperature need to
be cooled to 41°F within 4 hours.
" Ask: How do you know if the food you are
cooling has met these requirements?
Answer: Check temperature with a
thermometer. Have SOPs for cooling food
that have been tested and are monitored.
" Ask: How could you reduce the chance of
human error during the cool-down process?
Answers may include:
" Do you have a closing checklist? Is “Cool
Hot Foods” on the top of the closing-to-dolist?
" Adjust shelves in your walk-in to no more
than six inches apart so it’s impossible to
put a stock pot full of hot food in to cool.
This also prevents employees from stacking
several pans of hot food on top of each
other.
" Train and monitor employees.
" Review your menu. What
foods are cooked in advance
and require cooling? Can
some of these foods be
cooked and served the same
day, so you avoid the chance
of human error during the
critical cool down process?
" Write a SOP for cooling each food item.
Include cooling in the recipe. Include the
corrective action of improperly cooled
food—if not cooled to 70°F within 2 hours,
it must be re-heated to 165°F for 15
Teaching Activities for the Classroom Setting or Onsite Inspection
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o If they use the boiling water method,
check to see if they adjust for altitude.
Water boils 1 degree lower for every
550 feet above sea level. 2000 feet is
the highest point in Minnesota where
water boils at 208 degrees.
seconds within two hours and then attempt
to cool it properly OR throw away the food.
" Schedule the cooling process so that
someone is on hand to take the internal
temperature of the food.
How to Use a Thermometer to Check
Food Temperatures and Calibrating
Thermometers
Onsite Activity
# Ask employee/manager to get their
thermometer and have them demonstrate
how they use it to test a food temperature.
Remediate any errors you notice.
# Ask about procedure of taking food
temperatures.
# Ask the employee/manager to show you
how to calibrate a thermometer. Remind as
necessary.
# Notes/reminders about
calibrating
thermometers:
o Turn nut clockwise
to make warmer.
Counter clockwise to make cooler.
o If they use the boiling water method,
check to see if they adjust for altitude.
Water boils 1 degree lower for every 550
feet above sea level. 2000 feet is the
highest point in Minnesota where water
boils at 208 degrees.
Classroom Activity
Demonstrate how to
use a thermometer
correctly and how to
calibrate using an
ice/water method or ask
for a volunteer to show the class how to use a
thermometer and another volunteer to calibrate
it. Remediate as necessary.
# Notes/reminders about calibrating
thermometers:
o Turn nut clockwise to make warmer.
Counter clockwise to make cooler.
References
1. University of Idaho Cooperative Extension
System, The Cold Facts about Safe Food
Poster. 1994.
2. Food Safety Illustrated. Fellow Operators
Pass along their Best Food Safety Ideas
and Product Finds. Spring 2003, p. 15.
3. Health Service Agency—County of Santa
Cruz, Cooling Foods Properly, Santa Cruz,
CA.
4. Minnesota Food Code, Cooling Hot Foods.
5. University of Florida, Cooling Depending
on Food Type and Containers. 1998.
6. Florida Department of Business and
Professional Regulation Division of Hotels
and Restaurants. Improper Cooling is the
Major Cause of Foodborne Illness.
University of Florida, DBPR Form HR
5030-061. 2001.
7. DuPage County Health Department.
DuPage Safe Food: The Problem with
Cooling Food.
www.dupagehealth.org/safefood/industry/q
a/cooling3.asp
8. International Food Safety Council. The
Right Way to Chill Foods. ServSafe
Instructor Guide, p. 7-15.
9. Ministry of Health Malaysia. Guidelines
Cook Chill Catering. Food Quality Control
Division MOH Malaysia.
Developed by Suzanne Driessen, Regional Extension Educator,
University of Minnesota Extension Service, [email protected], and
Joe Jurusik, Registered Sanitarian, Hennepin County Health
Department, [email protected], February 2004; Revised
September 2004.
Teaching Activities for the Classroom Setting or Onsite Inspection
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