Is it possible to identify the source of a protein hydrolysate I have a powder which only declares to be "Protein Hydrolysate"
Meaning that the all the protein has been broken down.

We've tried to identify the source of the powder with DNA research. But no usable DNA (parts) where found.

Is there a way to identify the source of this powder? (ie. chicken, pork, cow, shark, dolphins or unicorns)

For clarification, we failed to find any DNA in the powder. so we're looking for alternative ways to analyse it.
DNA is not a protein, as @MARamezani states. See http://www.answers.com/Q/Is_DNA_a_protein.
There is a prevalence (or lack) of some amino acids in certain sources. For example, maize ("corn" in America) is deficient in tryptophan and lysine, so if your sample is short on those two, it is more likely that it is from corn. A list of some foods and amino acid content is at http://www.ljhs.sandi.net/faculty/aquesnell/Biology%20Notes/Chapter%204/4.8-4.13/Essential%20Amino%20Acids.pdf [there appear to be some errors, though]. According to that source, yeast may be deficient in phenylalanine, so that is another indicator.


You would need an analysis of the relative abundance of each amino acid, some reference showing their abundance in various sources, and additional analysis to calculate relative abundances in a mixture, e.g. corn supplemented with yeast hydrolyzate.