|MadSci Network: Agricultural Sciences|
This was referred to me as a microbiology question, which it is not. Although souring of milk is caused by bacteria, the lactic acid could as well have been added to the milk from some other source. In any case, calcium as lactate appears to be as nutritious as calcium in other forms -- calcium lactate is listed as one of the most biologically available forms of calcium. I have not found anything to suggest, in the way of specific methods of analysis. In the U.S., the most respected reference to this kind of information is: Official Methods of Analysis of the AOAC (Association of Official Analytical Chemists) International, 16th ed., Arlington, VA, 1995. If you can find a copy, it should offer more than one method that is current.
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