HACCP aims to prevent the problem within the process instead of looking for it in the finished product. It has seven principles: identify the hazards (biological, chemical, physical), choose the critical control points (CCPs), set a critical limit for each, define the monitoring method, write down the corrective action to be taken when the limit is exceeded, verify that the system works and keep records of it all. Its source is the international Codex Alimentarius principles; certification standards such as ISO 22000, BRCGS and IFS are built on it. In Turkey, food hygiene legislation requires food businesses other than primary production to have a system based on HACCP principles.
Refrigeration is right at the centre of this plan. Typical critical limits are along these lines: fresh meat and chicken store +4 °C at most, frozen store −18 °C at most, meat cutting room +12 °C at most; the exact values are set by the business’s own plan and the relevant product legislation. Monitoring is continuous, with a temperature recorder; if the limit is exceeded for longer than a set time, an alarm is raised. The corrective action is written down in advance: the product is moved to another room, its temperature is measured, it is set aside if necessary and service is called. Who will measure and who will decide are also named in the plan.
For those who install and operate the refrigeration system, this translates into concrete terms as follows: a calibrated recording probe, preferably independent of the controller; comparison of the probes with a reference thermometer once a year; door-open, high-temperature and defrost-not-terminated alarms; a recorder that keeps its data during a power cut as well. Remote monitoring delivers the alarm to the responsible person’s phone at night and at weekends too. The brief rise in air temperature during defrost shows up in the records; for this reason the limit should be defined in terms of product temperature and time, not air temperature.
Hygienic design is also part of the plan: washable panels with food-grade surfaces, rounded corner profiles, a sloping floor and trapped drain, drainage that does not drip water into the room, a ceiling that does not form condensation, and lighting protected against breakage. The evaporator fins and tray are cleaned during periodic maintenance, because cold-loving bacteria such as Listeria can harbour on cold, wet surfaces. The first document asked for at an inspection is the temperature records; if there is no record, the action is deemed not to have been taken. For the temperature limits of products the food storage conditions guide is the starting point.