I used a barrier cream (zinc based) for about 6 months before things got better.  I find that if I eat blueberries or too much tomato the burn is much much worse.  I also found a cream (Dimethicone) worked brilliantly and wasn't as sticky or pasty as zinc.  Calmoseptine, which some people think is brilliant didn't work well for me as the menthol in it was too hot for my delicate nether regions.

Flavored coffee from starbucks probably has a lot of sugar, and people complain of sugar causing pouchitis, but I don't know that it causes the burn, but it may cause extra excretion due to the diuretic effect. (A coffee & cigarette first thing in the morning used to be a sure path to a BM back when I had a colon.) I like the calmoseptine because of the menthol cooling action.  Zinc/calamine also protects and helps heal the tender tissue. I have also used non-menthol zinc pastes on my bum like Penaten cream.  Someone suggested Desitin early on but that didn't work for me, partially because I don't like the smell of it.

My doctor put me on tincture of opium to slow down the guts.  I would not recommend that-it didn't help at all with the burn, and made me feel emotionally unstable.  I would recommend a small amount of fine ground, organic psyllium powder before a meal mixed with water.  I wish my doc had recommended that when I got my pouch.. I went for years with the poop rushing through!  Now I take about a teaspoon before a meal with about 6-8oz water.  I would experiment with what works for you and start with a small amount. This helps decrease the frequency and also coats the intestinal membranes with a mucous like substance and protects them somewhat. Put it in a small jar and shake it and drink it down quickly so that it doesn't thicken before you get it down.  Then put more water in the jar, shake, and do it again to get the rest out and to get the recommended amount of water. 

Good luck and I hope you discover the method for a happier bum ASAP!