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[DgNt]

I brewed my 6th beer yesterday and the biggest part of brewing I don't get is calculating IBUs, and more importantly, knowing how the hop bitterness will come through in the final beer. Calculators seem to be all over the map. For instance, the recipe I followed called for the following: .5oz Centennial 10%AA @ 60 min1.0oz Mt Hood 7%AA @ 30 min1.0oz Willamette 5% @ 15 minfor an estimated 43 IBUsWhen I brewed I used: .7oz Centennial 9.7%AA @ 60 min1.0oz Mt Hood 5.5%AA @ 30 min1.0oz Willamette 4.7% @ 15 minOG was 1.055, BG was 1.043ish; Pre-boil volume was about 7G with about a gallon boiled off and a half gallon or so of trub loss.Brew Pal calculated IBUs my actual brew at 44 IBUsBeer Calculus calculated my actual brew at 57.1 IBUsBrew 365 calculated my actual brew at 44.1 IBUsGranted those are theoretical as my system losses and boiling gravity curve probably vary a bit from the calculator's assumptions. The recipe is the Amber Ale recipe in Palmer's How to Brew and was followed exactly with the exception of the AA% and the amount of Centennial that I increased. My deviations from the recipe should have resulted in lower IBUs (the only increase was to the Centennial by .2oz which doesn't even offset the lower AA% of the hops I used).I guess I'm posting to get some level of comfort that a particular model will work well for me/my system. I'm still mostly following recipes but will start deviating from "proven" recipes and ultimately start making up my own completely... knowing how to calculate bitterness accurately would be helpful. Is there any way I can objectively measure my IBUs? Tasting is too subjective; especially as the malt and hops play off one another. For my next brew I'd like to try a Loose Cannon or 60min clone, so the hop schedule/profile will be a bit more complex (and important); I don't want to over or under shoot too much on the results. Also, can I expect to get lots of hop flavor and aroma homebrewing or will most of it boil/evaporate off? Both of those have wonder flavor and aroma in my opinion.Thanks!

[Malzig]

You're going to need to pick a single hop formula and stick with it. If you're doing full volume boils, I'd suggest Tinseth. Then, you're going to need to look at the beers you've made and see how the number compares to the taste. Try to get a handle of what 35 or 45 IBUs taste like in a 1.050 Pale Ale that finishes dry, or a Brown Ale that finishes higher. Maybe compare your beer to a similar commercial beer with a known IBU. Then, consider those comparisons when you design your recipe. I remember seeing a paper once that showed that a half dozen brewers following the same recipe ended up with actual measured IBUs of +/- 25% of the prediction (that would be a range of 30-50 for a 40 IBU beer), so eventually you need to get some degree of comfort with what the calculation means on your system.Also, be aware that you will often need to make a beer, taste it to determine that it would have been better if it was made differently, then make adjustments the next time you brew the beer.