How to use blast chillers properly in your food business.

A blast chiller is a special unit designed for the rapid cooling of food from a high temperature to a low temperature suitable for the placement of these foods into a refrigerator or freezer.

Staff must follow the safety points above in order to achieve a consistent level of food safety.

Time and temperature

Foods should be placed into the blast chiller within 30 minutes of cooking, then chilled down in the unit within 90 minutes before placing into a refrigerator or freezer. Use the pre-built cooled food task inside Pilla to record a sample of foods cooled in the blast chiller. You can read more about cooling food procedures here.

The length of time the food takes to chill should be recorded including the start and finish time of cooling and the start and finish temperature of the food must also be recorded.

Staff should aim for final cooling temperatures of below 3°c if possible but below 5°c is acceptable when the 90-minute maximum cooling time is reached.

Staff should understand that long cooling periods can potentially allow spores to germinate resulting in vegetative bacteria growing and possibly forming toxins in the food.

Staff training

Blast chillers must only be operated by trained staff who must follow the manufacturer’s instructions for safe use.

Manufacturers recommendations

Blast chillers should be sited in accordance with manufacturers recommendations. They should be sited for ease of use and to facilitate cleaning or maintenance work.

Date labelling and covering food

Once cooked food has been cooled appropriately it must be covered appropriately and date labelled with a use by date of three days inclusive of the day of cooking and cooling.

E.g. cook and cool Tuesday, use by end of service on Thursday.

Maintenance

Blast chillers must be regularly checked and maintained paying particular attention to vents that may become blocked and will significantly affect the unit’s ability to cool foods quickly.

Contingency plans should be considered regarding how foods will be cooled in the event of blast chiller breakdown.

Cleaning

Blast chillers must be cleaned frequently as they come into regular contact with high risk foods. They will also come into contact with allergens, therefore frequent cleaning and disinfection should take place, in the case of the handling of allergens both before and after use. Any cleaning should be included on the cleaning schedule.

Considerations regarding food size and shape

Food items to be cooled should not exceed 2.5kg (6lb) in weight and 50mm (2 inches) in thickness or height.

Large poultry carcasses should be broken down into sections not exceeding these sizes and measurements.

It is also good practice to ensure that the depth of foods in containers does not exceed 50mm.

Inbuilt probe

For any unit that has an inbuilt probe, this must be cleaned and sanitised before every use.

Food volumes

It is advisable not to cook more than 10 litres of liquid and bulk volume foods, such as stews, gravy and pie fillings at any one time.

The capacity of the blast chiller should not be exceeded.

Ensure enough time has elapsed for cooling before beginning the next batch of food.

Corrective actions if things go wrong

• •Arrange alternative methods of cooling foods, in the event of a fault or breakdown of the blast chiller.
• •Call an engineer in the case of a fault or breakdown.
• •Food that has not been labelled correctly, consider discarding.
• •Discard food that has not been cooled correctly or safely.
• •Cook smaller portions or volumes to help in the quicker more efficient cooling of foods.
• •Prepare in advance and allow adequate time.
• •If staff do not follow the safety points retrain them and give extra supervision until competency is shown.