Beersmith2- Boil volume- easy question

[paparker21]

Okay, so i just had one of those "awww duh!" moments as I was responding to someone elses thread....

My beersmith is configured for a boil volume of 3 gallons

I usually steep my grains and top up to 3 gallons.... and then promptly add like 6 lbs of DME which brings my wort level up to about 4 gallons in the BK, pre-boil...


I need to correct this to have my hop utilization be more accurate I suppose...so what's going to be my best approach-- increase boil volume to 4 gallons in beersmith or add my DME prior to topping off so i only top off to 3 gallons?

I can see how the first would likely be easier-- but running 4 gallons I have a heck of a time with boilovers in my 20qt pot. I'd much rather do a 3 gallon boil for simplicity though

Or, am i wrong about there even being an issue? Is that DME supposed to be included in my pre-boil volume or does beersmith think i've got 3 gallons then add the dme and account for its extra volume?

/i'm so confused now.

 

[Schnitzengiggle]

Well the higher concentration of sugars in your wort is going to reduce your hop utilization, so if you are boiling 4 gallons, and all of your DME is included in your boil, then you aren't going to be getting full hops utilization anyhow.

I am assuming you are making a 5 gallon batch by topping up with water. If that is correct, then I would shoot for a boil gravity of 1.040-1.050, then add the rest of your DME at 5-10 minutes left in the boil. This will increase your hops utilization, and allow you to leave your boil volume alone, if you are more comfortable with boiling the 3 gallons.

As for BS knowing whetherthe DME is included in your pre-boil depends on whether you enter a time for late-extract, or add after boil. So when you are entering your DME amount right underneath the amount box there is a late addition box, and a checkbox for after boil. Those will let BS know when you are adding your DME, if you do not enter anything into them, then BS will assume that all of your extract is included in your boil volume.

By altering the amount of extract you include in your boil you will increase your hops utilization due to the lower SG, adding the rest of your DME late in the boil or at flame out will bring your SG to where it needs to be for your OG.

Remember that extracts have already been boiled, thats how it is produced, therefore you don't really need to have a "hot-break" when using extract, all you really need is the IBU contributions from the hops, and that lower SG wort will allow you to achieve the higher utilization you seek. Using the late-addition, and after boil features will help make an improvement to your beers, and BS should recalculate your IBU's when doing so.

 

[paparker21]

Excellent, good info there schnitz. I am aware of the effect boil gravity has on hops utilizaiton and had thought about starting to mess around with using a far lower amount of the DME upfront but had already ordered all my ingredients last time and was mid boil when i thought about it.

I'll definitely try and reduce boil gravity to the 40-50 pt range as that should help save me a little bit of expense in how much hops i need (through increasing utilization). Keeping the lower boil volume is just icing on the cake i think.

Thanks!

 

[House12]

The effect of boil gravity on hop utilization is really not very clear. What was assumed to be diminished IBUs due to boil gravity is more likely lost bitterness from alpha acid clinging to hot break. Since DME has considerably less hot break than all grain boils, adjusting for gravity probably isn't worthwhile. That said, late extract addition is still a good idea due to melanoidin reactions. Hop utilization is such an imprecise science, all that really matters is the HBU calculation of your recipe. If you're lucky, IBUs might calculate within 20% of real bitterness levels.