Expert: Dr. Henry Boyter, Jr. - 5/2/2005

Question
Thank you for your quick reply!

Is there a procedure reference for this?  We are not attempting to make it, only find out the materials used to synthesize this item.  This information will be supplied to a Rabbi to ensure our process is kosher.  Thanks again for your help.

Mark  

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Followup To
Question -
I was wondering how Bromocresol Purple, a pH Indicator Dye, was synthesized.  Mainly, I was wondering what the individual componets were?  We were going to use this dye to culture lactobacteria, which will then be used in the fermentation process of a food.

Any help would be appreciated.
Answer -
If you mean bromcresol purple, it is made by treating o-cresol red with bromine in glacial acetic acid. That is a reaction only a very experienced chemist should ever try.

Answer
The reference indicated the procedure was in a 1926 chemistry journal, JACS Vol48, p2216 (or reference in that journal).  Unless you find the synthesis on the web through a google search, you are probably out of luck.  You might also try contacting a chemcial company in Israel for their help.