To reduce heat resistant spores, which can be vital in the pasteurized milk, a bacteria clarifier can be integrated. This is recommended for the production of low nitrate cheese.
Frequently, instead of full skimming, the adjustment of a defined fat content below the raw milk fat content is required. This is achieved by a partial returning of cream into the skim milk. Optionally manual standardizing equipment or the well-proven fully automatic GEA standomat are available.
In some cases a deaerator is required to deodorize the milk.
A high pressure homogenizer provides a size reduction and an even distribution of fat globules as well as added powder particles in order to prevent sedimentation or creaming during storage.
Depending on the customer’s production philosophy the bacteriological status of the pasteurized milk can be improved by increasing the pasteurization temperature. This is one of several measures to increase the shelf life of the final product.
Extended holding time
An additional effect of the same kind is obtained by extending the holding time. Also some products require this strong heating to achieve a modification of the chemical structures of the milk. Mostly this is used for the processing of yoghurt milk.
Differential pressure control
The European dairy legislation requires a safety feature against a possible contamination of pasteurized by unpasteurized milk in case of a plate crack in the heat exchanger. This can be ensured by maintaining a higher pressure on the pasteurized milk side by means of a booster pump and a constant pressure valve.
If the pasteurized milk is further processed by fermentation, an increased outlet temperature of 27 °C – 40 °C may be required. In this case, the ice water cooling section may alternatively be used for cooling or for heating. This option is suggested for the production of cheese, yoghurt, kefir or fresh cheese.
The semi automatic control included in the basic version can be upgraded to fully automatic control. In an automatic environment a signal exchange via digital I/Os or via Profibus is possible.
Cream is discharged from the separator at approx. 55 °C. For a longer storage it should be cooled down to 8 °C – 12 °C.
The cream discharged from the separator is not pasteurized and has to be considered as raw cream. Depending on the further processing it has to be pasteurized which is done usually at 95 °C for 15 s. The cream pasteurizer can be placed on one skid together with the milk pasteurizer.