Beersmith

[madisonmasher]

What are people's thoughts on how beersmith calculates IBU? Is it often too high? Low? I know it doesn't think you are adding IBUs when you add during whirlpool and dry, but what about 60 and 20 minute additions? Thanks for the help!

 

[BobBailey]

The method Beersmith uses to calculate IBUs can be selected by the user. Tinseth, Garetz and Rager are all options. You may select one by going to, Tools/Options/Bitterness, where you'll find a drop down. I'm not aware of any software that uses any other models. The accuracy of any of these models is questionable, but any of them may be put to good use.

Both later versions of BS2 and BS3 do calculate bittering from steep/whirlpool additions and also allow a selectable option to estimate IBU adjustments for kettle additions that remain in the kettle while other additions are steeping/whirlpooling. Studies on calculating IBUs from dry hopping are still in the early stages. I'm sure you'll see them appear in brewing software, including Beersmith, once reliable ways of estimating levels are achieved.

Beersmith allows you to make adjustments to the overall utilization % in your equipment profile. In addition, Beersmith 3 will adjust overall utilization based on your altitude when you enter it in the appropriate box, also in your equipment profile.

If you look at, Tools/Options/Bitterness, you will find other more specific adjustments you can make including those for: First Wort Hoping, Mash Hopping and also for Leaf, Pellet and plug hops. These options allow you to dial in your hop use in the same manner that Beersmith allows you to customize almost every other aspect to suit your taste.

Personally, I use Tinseth and have adjusted for altitude, 10% for bagging my kettle hops and an additional 5% so that my perception of bitterness puts my beers in line with similar craft brews.

 

[SoCal-Doug]

It's a starting point. In most cases its calculations are "safe". Not only will software be a bit off sometimes, but a brewers processes and practices can cause IBU's to be different than expected.

Brew, taste, enjoy, and adjust as needed.

 

[ScrewyBrewer]

"Utilization numbers are really an approximation. Each brew is unique; the variables for individual conditions, i.e. vigor of the boil, wort chemistry, or for losses during fermentation, are just too hard to get a handle on from the meager amount of published data available. Then why do we bother, you ask? Because if we are all working from the same model and using roughly the same numbers, then we will all be in the same ballpark and can compare our beers without too much error. Plus, when the actual IBUs are measured in the lab, these models are shown to be pretty close." ~John Palmer (How To Brew)

 

[Oginme]

It's a starting point. In most cases its calculations are "safe". Not only will software be a bit off sometimes, but a brewers processes and practices can cause IBU's to be different than expected.

Brew, taste, enjoy, and adjust as needed.

"Utilization numbers are really an approximation. Each brew is unique; the variables for individual conditions, i.e. vigor of the boil, wort chemistry, or for losses during fermentation, are just too hard to get a handle on from the meager amount of published data available. Then why do we bother, you ask? Because if we are all working from the same model and using roughly the same numbers, then we will all be in the same ballpark and can compare our beers without too much error. Plus, when the actual IBUs are measured in the lab, these models are shown to be pretty close." ~John Palmer (How To Brew)

I recommend checking on Experimental Brewing's report and podcast about "The IBU is a Lie -- kind of". They can be found at: https://www.experimentalbrew.com/experiments/writeups/ibu-lie-kind and https://www.experimentalbrew.com/podcast/episode-32-ibu-lie.

The IBU calculation provides the brewer with a reference point which may be more or less accurate depending upon each brewer's process and water chemistry. While I do not quote the numbers as being and accurate representation of what an actual test result may be, they do give me a relative value which I can relate to my perception of bitterness after sampling commercial beers with tested and "known" IBU values.

Both quotes above are the best way to approach the calculation of IBU in your beer. First as an approximation and second as a reference to adjust the hop additions to meet your sensory perception and expectations.