On 10-09-14 11:26 AM, Constance Allen wrote: > I use powered citric acid that I bought from San Francisco Herb. I > wonder if it could be a substitute for "vinegar powder"' > > Cheers, > > Constance Allen Hi Constance....how ya doing? Nope, nothing like acetic acid. That constitutes hypo which is what Rich uses to fix his photos. Smells like vinegar, but is not quite the same! Citric acid is derived from citrus fruits amongst other things. Used to give a sour taste to foods and as a cleaning agent, or more specifically a substance in some cleaning agents. Cheers, old Doug in BC