Buffering capacity of dairy products
Résumé
The buffering capacity of milk products is an important physico-chemical characteristic that corresponds to the ability of the product to be acidified or alkalinized. The parameters of this value depend on several compositional factors including small constituents (inorganic phosphate, citrate, organic acids) and milk proteins (caseins and whey proteins). Natural and induced variations in the composition of milk affect this physico-chemical parameter. Thus, some technological treatments and physico-chemical changes, such as heat treatment, membrane separation technology, high-pressure treatment and salt addition, result in a buffering capacity specific to the transformed product (heated milk, retentate, fermented milk). In cheese manufacture, the preparation of cheese milk and the cheesemaking parameters have major influences on the buffering capacity of the curd at mould removal and during ripening. Cheese quality is therefore affected since ripening, via enzymatic activities and microbial growth, is modified.