BeerSmith and 0min vs Steep/Whirlpool

[hollywoodbrew]

Why is it that beersmith gives me 0 IBU for a 0min addition, but a substantial IBU for a 30 min whirlpool? This doesn't make sense to me.

If I'm putting in an addition at flame out, then waiting for temp to drop to 180 F to add my whirlpool addition, shouldn't the 0min register more IBUs than the whirlpool addition?

Am I doing this wrong?

 

[dyqik]

Beersmith calculates IBU contributions to the recipe on a per-ingredient basis. It has to assume that you don't whirlpool the boil additions (after all, you might not whirlpool), and when calculating flame out additions, it can't know how long it takes you to cool the wort, so it has to assume zero time (pretty accurate if you have a good CFC or plate chiller and start running off wort immediately through it into the fermentor).

The whirlpool calculation is a recent addition that calculates the IBU from each whirlpool/hopstand addition. Since the calculation is done on a per-ingredient basis, it doesn't include hops previously added to the wort in the calculation. Obviously, hops that are boiled for any length of time before being whirlpooled can't be calculated as a simple whirlpool addition (because they've already given up a lot of their bitterness), but whirlpooling them will increase the IBUs extracted.

So you've got a couple of options if you want your process to more accurately follow the Beersmith model in order to hit the IBU numbers: Remove your boil hops at flameout, and/or move your flameout hops to the whirlpool (and/or calculate them as such). Remember though, IBU calculations are somewhat inaccurate generally (particularly for late additions?), and there's a couple of different formulae you can choose between.

 

[joshesmusica]

Reason is that it doesn't assume that you will drop the temp for the whirlpool addition. So drop the temp, but then type in 0 for the length of the whirlpool addition and you'll get a better approximation of the ibus.
Also the reason why the 0 min addition doesn't change when you add a whirlpool addition, yet the whirlpool addition is more ibus, is because it's adding all of the extra ibus from all of your additions that get some extra isomerization into the line for the whirlpool addition. So you're not actually getting the extra ibus from the hops in that addition, but because of that addition you'll get those extra ibus.
So like I said type in 0 and you'll be more accurate. Unless of course it takes you 15-20 mins to cool down to below 180, in which case your 0 addition will add more ibus than it's saying it is.
I personally don't understand the point of differentiating between a 0 min addition and a whirlpool addition unless you're allowing the 0 to sit at high temps before cooling it down for the whirlpool addition. But then if you're doing that, you need to type it in as a whirlpool addition in order for bs to add on the extra ibus.

 

[hollywoodbrew]

So, say I toss in the hops at flameout, and start chilling. It takes about 30 minutes to get to 90F. How would I represent that in my beer smith recipe? Whirlpool addition for 15 min?

 

[joshesmusica]

You could do that. Or you could just time how long it takes to get below 180, then type that amount in. In the end, the difference won't be that much, and it's very unlikely you'll be able to perceive a difference between a couple of ibu points if you were to try them side by side.

 

[hollywoodbrew]

Thanks. I guess the takeaway is that, it's really hard to estimate IBUs accurately for late additions, but if you're consistent, you will get repeatable results.

 

[joshesmusica]

Yeah pretty much.