Fuente: WIPO "milk" In the manufacture of cheese, butter or margarine, milk to be used for preparing a bulk starter is contacted with an ion-exchange material for substantially complete removal of the calcium content i.e. to less than 20 parts per million; the calcium-reduced milk is of value since it is bacteriophage-resistant. According to a comparative example, 10 gallons of calcium-reduced milk of calcium content 9 parts per million and a similar quantity of untreated milk were inoculated with 1 per cent. of a starter culture and both were immediately infected with sufficient bacteriophage to ensure lysis of the starter culture and cessation of acid development in the milk. After 16 hours at 75 DEG F. the milk starter had developed only to an acidity of 0,3 per cent. whereas Cheshire cheese was produced with the calcium-reduced milk, the time from rennetting to milling being 3 hours 50 minutes.ALSO:Milk is contacted with an ion-exchange material for substantially complete removal of the calcium content, i.e. to less than 20 parts per million. Milk may be contacted with a weakly-acidic cation-exchange resin of the carboxylic-acid type in which the major part has been converted from the acid form into the alkali form, so that the milk after contact has a pH of about 7. The calcium-reduced milk is of value since it is bacteriophage-resistant and may be used for preparing the bulk starter in the preparation of fermented milk products. Bacterial nutrients and a calcium sequestering agent may be added to the ion-exchange treated milk which may then be reduced to a powder for reconstituting with water when required. A composition consists of 92 per cent calcium-reduced milk solids containing 3 per cent butter fat and minor proportions of enzyme digest of casein, corn steep liquor, sodium acetate and a sequestering agent such as ethylene diamine tetraacetic acid disodium salt.