I believe milk has a pH of 6.5-6.7 which is ok, while drinking water is about 7. But maybe not the best for pre-mixes for many days at a time.
From this 1996 study:
"Brent C. Trela and Andrew L. Waterhouse*
Department of Viticulture and Enology, University of California, Davis, California 95616"
http://pubs.acs.org/....1021/jf9504576The conclusions state the following:
trans-Resveratrol should be handled with caution, but can be handled in the laboratory without stringent lighting precautions, whereas cis-resveratrol cannot.
Laboratory lighting conditions favor an equilibrium of about 91% cis-resveratrol.
Low pH causes cis-resveratrol isomerization to the trans isomer, a sterically more stable form. Some literature reports of cis-resveratrol are inaccurate and were addressed here.
It appears that at Ph of Pepsi (no, I personally prefer Pepsi over Coke.. sorry guys) has a Ph of about 3 or lower, and maybe good to "pre-mix" for those concerned with a very old batch of res that has turned into Cis-resveratrol... well, at least for those that don't mind the sugar high... :D
Another quote from the study:
cis-resveratrol degraded at pH 10.0 with a half-life of 63.7 h (Figure 7). cis-Resveratrol was stable at pH 7.0 (CV ) 0.7%), and less stable at pH 3.5 (CV ) 2.6%); however, at pH 1.0 isomerization to trans-resveratrol was efficient after 22.8 h (t1/2), 50% of the cis form had isomerized to the trans isomer nm).
and another...
Sample dry-down operations with rotary evaporation
were checked for resveratrol stability, and contrary to
Pezet et al. (1994) and McMurtrey et al. (1994), no
degradation of trans-resveratrol was observed after
evaporation of alcohol, confirmed by Jeandet even when
heated at 40 °C (unpublished results) or in buffers at
various pH values except for the pH 10.0 buffer.
of course, your gut has a Ph of about 1, so that may help as well.
Edited by Anthony_Loera, 24 July 2009 - 03:57 PM.