Thursday, 1 November 2012

Why use temperature probes?


When Temperatures Rise

The importance of food temperature probes, using them correctly, and how to test your probe to ensure it’s working correctly.

It’s a crisp autumnal evening with clear skies and you’re attending a fireworks event...the smells of bonfires and burgers fill the air. You discover the display is going to be a random pile of fireworks that will have a torch thrown upon them at any given moment, would you stay to watch or would you get out of the danger zone?

This risk could be likened to not using a food temperature probe in your food business; you would be giving your customers the same unpredictable and possibly lethal experience. The only difference being that your hazard is made from lamb or beef, not gunpowder. Failure to use a probe correctly and consistently has to be one of the most common failure points within a food business when it comes to hygiene inspections.  It’s estimated that 70% of businesses don’t use or test their probes correctly, and 55% don’t even possess a working food temperature probe!

5 tasks you cannot do without a probe
1.       Checking temperature of frozen and chilled deliveries as they arrive
2.       Checking your fridges and freezers are working  independent of their gauges
3.       Individually probing every cooked dish to ensure 100% confidence
4.       Probing items in ovens to check they have reached 75 degrees or above
5.       Checking the core temperature of food in your hot-hold area

Storing, freezing, thawing, cooking and serving food all have different temperature requirements, knowing these correct temperatures is essential for reducing risk of any bacterial contamination within any food handling processes.

The Danger Zone is the term used for the temperature range in which bacteria can grow in food. This is between 5 – 63°C so it essential to monitor food temperatures from delivery to storage right through preparation, cooking, serving or freezing. It’s worth stating that frozen goods should be stored at -18 to -25°C, including delivery right into your premises from any supplier. 

Ways to keep high-risk foods out of the danger zone:
  • Check temperatures as food is delivered to your workplace (use a probe thermometer)
  • Refrigerate raw, highly perishable & high risk foods immediately after delivery
  • Keep food refrigerated until it is needed for preparation or serving.
  • Cook food for at least 2 minutes at 75°c right through to the centre or the thickest part of the food (82°c for 2 minutes in Scotland)*
  • Serve hot food at 63°C or hotter
  • Cool food rapidly, so that food spends as little time as possible in the Danger Zone.
  • Thaw frozen food in a refrigerator so that the outside temperature of the food cannot reach Danger Zone temperatures whilst the inside is still frozen.
  • Re-heat food adequately to 82°c to kill most bacteria.
  • Serve within 20 minutes once the food has been prepared or cooked
Cooking at high temperatures kills most bacteria, provided that the food is cooked for long enough. Always remember do not keep food in the Danger Zone any longer than necessary. Keep hot food really hot and cold food really cold and only reheat cooked food once.

Our quick guide to correct use of food probes including testing their accuracy:

Correct probe use
1.       Clean the probe thoroughly and disinfect it before and after use in order to prevent cross-contamination.
2.       Insert the probe and wait for the display to stabilise before taking a reading.
3.       Keep the probe part of your thermometer clean, otherwise it could cross-contaminate food.
4.       Anti-bacterial wipes are an easy to use method of cleaning the probe.
5.       Make sure you throw away the wipe after each use.
6.       Do not leave a digital thermometer inside your fridge or freezer, or on hot surfaces.
7.       If the battery is low, replace it immediately.
8.       You should check your thermometer is working correctly every month

How to check your Probe
To carry out a low temperature check, place tip of thermometer probe into crushed ice and cold water - leave for 5 minutes and then measure reading.  It should be should be between -1°C and +1°C.  To carry out a high temperature check, carefully place tip of thermometer probe into the steam from a boiling kettle of water and record the reading.  It should read between 99°C and 101°C.

 “[In June 2012] The Food Standards Agency has brought a successful prosecution against an Essex slaughterhouse for deliveries of over-temperature meat.... Seven of the offences concerned the delivery of meat from Elmkirk Limited to meat wholesalers based at Smithfield Market in London. Elmkirk Limited had previously had its approval to transport warm (more than 7°C) meat to premises in Smithfield withdrawn, but continued to do so...The other offence concerned a delivery of over-temperature meat from Elmkirk Limited to premises in Leeds. This was a journey in excess of two hours and the meat should have been chilled and kept chilled before and during transportation.”
As the case above suggests; there is simply no guarantee at any point of the process that rules are being followed. A probe removes the guesswork and helps protect your business and customer health, your Environmental Health Officer will expect to see evidence of this. Food probes are inexpensive (as little as £20) and there’s no excuse for not having one, using it properly, and documenting its use.