http://beerandwinejournal.com/ipa-experiment-report/
Haven’t tried this myself but I agree with the results based on changes I’ve made over the last two years of brewing and adjusting RO water.
What I’d like to see is how absolute numbers effect the flavor or perceived bitterness. By this I mean make two or three IPA’s with the same ratio, like 3 to 1, but have different sulfate PPM levels for each, like 50, 150, and 300.
If you listen to the broadcast (http://traffic.libsyn.com/basicbrewing/bbr11-07-13ipaexp.mp3), I was involved in analyzing the results. I also have the beers here and will be tasting them and trying to rate them. It was an interesting idea, but a kinda failed experiment. They simply asked which was most “hoppy” without defining what “hoppy” meant. In addition, the results were all over the place. One person said there was a tremendous difference in the beers, the next said he could hardly tell any difference.
Martin has said that chloride should remain under 100 ppm. In that light, ratios become meaningless and absolute numbers become important. If by raising the sulfate you need to go over 100 ppm chloride, then you can just throw the ratio out the window.
The ratio is definitely out the window when chloride exceeds 100 ppm. But for those interested in testing the effect of sulfate/chloride ratio, keep the chloride down around 50 ppm and boost the sulfate as desired to alter the ratio. You can do this in the glass, but the amount of gypsum you would be adding is teeny in many cases. Its easier to do when the volume of beer is larger. Remember, gypsum is 100% soluble at the low concentrations we enjoy in beer.
I only skimmed the experimental description yesterday, and I have yet to listen to the podcast, but I did note that to make the experiment easier, they dosed glasses of beer rather than brew multiple batches with different sulfate ratios. I have a rather large blind spot for biochemistry; is this a fair way to do the experiment? Is the perceived “hoppiness” only dependent upon the sulfate/chloride ratio after the fact, like adding salt to a cooked meal, or does the ratio come into play during chemical reactions going on in the kettle or fermentor?
I was part of the tasters. James brought the samples to our club Learn to Home Brew day.
It has to do with the sulfate in the finished beer, which I assume means that there’s no reaction in the kettle. Martin wrote about dosing in the glass a few months back and I have done it a number of times.