ServSafe Chapter 5
A thermometer used to measure the temperature of food must be accurate to what temperature?
+ or - 2 degrees
What is the temperature danger zone?
41-135; pathogens grow well within this range
What temperature range do pathogens grow especially fast in?
70-125
At what temperatures do most foodborne pathogens grow most quickly?
between 70 and 125
What are the 3 types of thermometers used in foodservice operations?
bimetallic stemmed thermometers, thermocouples, thermistors
While getting ready to check the temperature of a roast chicken, a chef dropped a bimetallic stemmed thermometer onto a prep table. What should the chef do next?
calibrate the thermometer
What are the general thermometer guidelines?
cleaning and sanitizing, calibration, accuracy, glass thermometers, checking temperatures
Maximum registering thermometer
indicates the highest temperature reached during use (dishwashing machines)
Which thermometer is limited to measuring surface temperature?
infrared thermometer
What is the flow of food?
the path of food as it moves from purchasing, receiving, storing, prepping, cooking, holding, cooling, reheating, and serving
Bimetallic stemmed thermometer
Checks temperatures from 0 to 220 degrees Fahrenheit; for checking hot and cold foods during receiving; useful during the flow of food; sensing area from tip to dimple
If purchasing a bimetallic stemmed thermometer for your operation, make sure they have what features?
calibration nut, easy to read markings, dimple
Food is being time-temperature abused whenever it is?
cooked to the wrong minimum internal temperature; held at wrong temperature; cooled or reheated incorrectly
What guidelines should be followed for infrared thermometers?
distance, barriers, manufacturers directions
What are the two methods of calibration?
ice point method and boiling point method
Boiling Point Method
involves adjusting the thermometer to the temperature at which water boils (212 degrees)
Ice Point Method
involves adjusting the thermometer to the temperature at which water freezes (32 degrees)
A food handler has finished trimming raw chicken on a cutting board and needs the cutting board to prep vegetables. What must be done to the cutting board?
it must be washed, rinsed, and sanitized
Thermocouples and termistors
measure temperatures through a metal probe; temperatures are displayed digitally; sensing area in tip; good for checking temperatures of both thick and thin food
Infrared (Laser) Thermometers
measure the temperature of food and equipment surfaces; quick and easy; do not need to touch a surface; less chance of cross contamination and damage to food; cannot measure air temperature or the internal temperature of food
Time Temperature Indicator (TTI)
monitor both time and temperature; color change appears in the window when time temperature has been abused during shipment or storage
How can you avoid time temperature abuse?
monitoring, tools, recording, time and temperature control, corrective actions
What probe should be used to check the temperature of a chicken breast?
penetration probe
What device can be used to record time temperature abuse during the delivery of food?
time temperature indicator (TTI)
How far must a bimetallic stemmed thermometer be inserted into food to give an accurate reading?
up to the dimple of the thermometer
What are the guidelines for preventing cross contamination between food?
use separate equipment for raw and ready to eat food; clean and sanitize before and after tasks; prep raw and ready to eat food at different times; buy prepared food
Penetration probes
use these to check the internal temperature of food, especially thin food (hamburger patties and fish fillets)
Air probes
use these to check the temperature inside coolers and ovens
Surface probes
use these to check the temperature of flat cooking equipment (griddles)
Immersion probes
use these to check the temperature of liquids (soups, sauces, frying oil)