At a collection centre the milk of many producers ends up in one tank, which makes it the most critical point for both the cold chain and the records. According to FAO, the natural inhibitors in milk limit bacterial growth for the first three to four hours after milking, and milk cooled to 4 °C within that period keeps its quality.
| Stage | Milk temperature |
|---|---|
| After milking, collected daily | 8 °C at most |
| Not collected daily | 6 °C at most |
| On arrival at the processing plant | 10 °C at most |
| On receipt for dairy production | 6 °C or below |
The limits come from Articles 55 and 57 of the Turkish Regulation on Specific Hygiene Rules for Food of Animal Origin. If the tanker runs late, milk waits in the tank; once the tank is full, warm milk added to it warms the mixture and the tank starts cooling again. The more often that cycle repeats, the closer the milk arriving at the factory gets to the limit.
On the records side, each batch gets the producer, milking and centre arrival times, arrival temperature, tank ID and the time it entered the tank. At tanker filling, add tanker ID, seal, departure and factory handoff times, and temperature. Without this, a problem disappears into the shared tank and nobody can later tell which producer's milk went in when.
