Bitterness/Color Analysis

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dwarven_stout

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First off, let me say that this topic is obviously not for you if RDWHAHB is your brewing mantra.

That said, I've been talking with a buddy.

Would anyone be interested in a service for minor analysis of beer, say IBU rating, color, maybe plating for cells? How about analyzing the AA content of home-grown hops?
 
I'd say the basic package would include:

Alcohol content
Apparent extract
True Extract
Original Extract
ADF/RDF
Bitterness (IBU/EBU)
Color (SRM/Tristim/EBC)

The capital investment required to do even these is pretty steep (distillation apparatus or GC, densitometer/alcolyzer, UV/Vis spectrophotometer, shaker, centrifuge, pipets...) and a fair amount of labor is involved as well. Then there are expendables i.e. gasoline (spectrographic grade) which must be properly disposed of (if you are going to do hops acids then add spectrographic grade toluene and methanol to the list). Can (or rather would) you do this for a price homebrewers would accept?
 
Thanks for your input. I'm familiar with the requirements of a setup to do SRM and IBUs. Reagent iso-octane is no problem. An actual hop AA breakdown is out of reach, but total AA % is easily doable.

Laying hands on a chromatograph would be sweet, but pretty unlikely. Still, alcohol analysis could be done by distillation.
 
There is no problem obtaining iso-octane - it's the pain of paying for it. Note that reagent grade isn't good enough. It needs to be spectrographic grade. As you are familiar with the procedure you may have noted that triple distilled gasoline from the pump is acceptable but I'm not distilling any gasoline in my lab! I also wanted to call your attention to the fact that you can't just dump it down the drain when you are finished with it. You have to have a proper disposal arrangement in place which is more expense.

There is a procedure for alpha and beta acids which is similar (same gear - shaker, UV spec) to what you do for the IBU's except that the hops themselves are extracted with toluene, the extract is diluted with methanol and absorption measured at two UV wavelengths.

Distillation is fine but time consuming (that's why I asked about how you would value your labor). Then how do you measure the distillate? A hydrometer isn't going to cut it. You can do it with a pycnometer and balance but that is also very time consuming. With a pycnometer I'd estimate 6-8 hrs for an analysis. With a densitometer you can cut that in half but a densitometer is a pretty expensive piece of gear.

What I'm getting at overall is that you need to add up the cost of the pipets, the petrol, the hydrochloric acid, the centrifuge tubes, the cuvets (if you use disposables and they are great for the color measurement), the depreciation on all the equipment and what you want to pay yourself per hour in setting a price. I expect that price will be more than most homebrewers want to pay unless you are willing to work for less than minimum wage. I do know a guy who is doing this (and making a living at it) but his customers are craft, not home, brewers.
 
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