steeping & sparge water pH - tannins

I think I know the answers to this but thought I would post to see what others have experienced.

I've read that in all grain the pH of the mash should be around 5.6 to prevent the extraction of tannins. I've also read that high pH water - will extract more tannins from grains than low pH. I have used well water for my brews, and live in "limestone" country. So I know that the water is hard, is high in alkalinity and pH. I was going to buy a swimming pool test kit to test pH and alkalinity. I have a water softener, but have used well water in my brews, as I thought the yeast would like the additional minerals.

As an extract brewer that uses specialty grains, my beers have had an after taste, which I've identified as the "sucking on a tea bag" taste. I know that high steeping temperatures will extract tanning, but I know that is not the problem here.

So, my questions are:

1. Should the steeping and sparging water pH be in the range of 5.6, or so?
2 .Is the high pH of my water the cause of the "tea bag" taste?
3. Do other extract brewers make pH adjustments in the steeping and sparging water?

Thanks,
Bill

First off, a couple of quick notes -- generally pH is a much greater concern for all grain brewers because it plays a big role in the conversion of starches to sugars by enzymes in the mash, and ultimately influences the final flavour of AG brews. For extract brewers (even PM brewers) the influence of mash pH is less important, mostly because the specialty grains that tend to get steeped in a PM are not required to be mashed and they also tend to contribute some acidity, making tannin extraction relatively difficult. Also, I should mention that the pH of your water isn't nearly as important as the residual alkalinity of your water. It is the residual alkalinity that determines how your water will affect your grain.

Having said all of this, I am not sure why you have ruled out tannin extraction as the culprit for your astringent off-flavours. This can actually be a relatively common problem for extract brewers, particularly if they put their steeping grains in a grain bag and then over sparge or wring the bag out to try squeeze out the remaining sugars from the bag. Any chances you are doing either of these things?

Regardless, it would be a good idea to test the pH of your runnings both before and after sparge to see how high they are getting. Anything above a pH of 6 could be drawing some tannins out. If it is above 6.5 you should probably acidify your water.

I'll add that aquarium test kits may be cheaper than the pool test kit, and would include pH, alkalinity, general hardness tests. You might even find a local aquarium shop that'll test your water for all three for free, or a couple dollars (just don't tell them you don't own an aquarium)

I have pretty hard, high pH, high alkalinity water here, and no tannins in my AG beers. So I'm not going to be quick to blame the water either, not directly at least.

my tap water pH is a solid 7.8, and just under 200ppm for carbonate hardness. general hardness is a little higher than that.

Thanks.
I didn't know you could over sparge. After steeping at around 150 deg F I will sparge with water that is between 120 - 150 deg F and will sparge until the color coming out of the grain bag is pretty clear. On stouts and darker beers that never happens; but on lighter brews, it will be a gallon or so.

Also, I have not squeezed the bag, so I know that is not the source.

Malcore, that is interesting your experience with high pH, hardness, and alkalinity water on your AG. I will try taking in a water sample to a pet shop.

I just know that I have a Kolsch that has been at 48 def F for about 8 weeks and it is like sucking on a tea bag. Not only that, but a lot of my lighter beers have an astringent taste to them.