Determine the fat and protein content of milk accurately and daily.
Measure milk volume or weight accurately and keep accurate records.
If powder is being added, use only high quality, low temperature, antibiotic free powder of known protein content. Low temperature powder is required to ensure that excessive denaturation of whey proteins in the powder will not impair milk coagulation and/or cause texture defects in the cheese. To ensure low temperature powder, ask your supplier to certify a whey protein nitrogen index (WPI) greater than 6.0.
Weigh accurately the weight of powder or skim milk added or the weight of cream to be removed.
Determine the composition of the standardized cheese and if necessary adjust the proportions of fat and protein in the cheese milk on succeeding days.
If bulk starter is being added reduce the amount of protein added by the amount of protein in the culture.
The maximum recommended level of skim milk solids in cheese milk is 11%. Normal milk contains about 9% skim solids so the maximum level of additional skim solids is 2%. If standardization requires more it is recommended to standardize by removing fat or adding skim milk rather than by adding skim milk powder. Another alternative is to add some powder and then complete standardization by removing cream or adding skim milk.
Without sophisticated metering equipment it is difficult to obtain exact standardization. Provided you have a milk analyser, you can do a final check of milk composition after the milk is in the vat and then 'fine tune' the P/F ratio by adding skim solids or cream as required.
It is not possible to predict the exact composition of the finished cheese. However, when manufacturing conditions and milk composition are the same from day to day, it is possible to predict the composition of cheese with greater accuracy and the proportions of fat and protein in the cheese milk can then be 'fine-tuned' accordingly. It is, therefore, important to keep accurate records.
Be careful to use the correct units when calculating and weighing and metering.