Last Minute Extended Boil Decision, How does that affect your hops additions?

[Hawaiianbrewer]

Aloha,
I had a question on last minute boil changes. Say your approaching your last 15 minutes of your boil and you see that you haven't boiled off enough to reach your desired post boil level or maybe your target OG is slightly low so you'd like to continue boiling. How do you adjust your hop addition schedule to make up for say your 30 minute addition now potentially becoming a 60 minute addition?

Or what if you've added your 15 and 5 minute addition as well and you realize you want to keep boiling, would you rather keep your boil as is so you don't loose your aroma additions or continue the boil to hit your OG target and sacrifice your aroma additions.

Maybe Im missing something but I've occasionally wanted to continue boiling but felt like it would mess up my entire hop schedule so I ultimately ended up with more wort at less gravity than I hoped. Any suggestions on this? Thanks-

 

[unseenat17]

The big consideration is that your IBUs will increase and your aromatics will decrease. Your 5-15 minute additions will no longer give you that robust aromatic taste that comes with the hop. If you do extend boil add more finishing hops (when your actually finished) and just remember it will be a bit more bitter than you accounted for (since you will have more utilization from the 5-30 min additions that turned out to be more like 25 - 50 min additions).

If your boiling in the same environment everytime...do a few tests with jus plain water. Start with x gallons, boil for 1 hour, and measure your final volume and do some simple math to figure out a percentage of reduction. Most boils in regular circumstances reduce by 10 percent. Basically if you started out with 10 gallons and boiled for an hour, you would end up with 9 gallons in the end. Doing this test for you environment with plain water is a cheap way for your brew to end up exactly how you want it on brew day without having to improvise in the middle of your boil. GL!

 

[day_trippr]

All good up to using the word "percentage". Boil-off isn't actually a function of percent of wort, it's a fixed rate based on boil vigor and surface area of the vessel. Ie, if you boiled 6 gallons and lost a gallon per hour, it'll still be a gallon per hour if you start with 8 gallons...

Cheers!

 

[Hawaiianbrewer]

Thanks for the responses. I get a pretty consistent boil off of about a gallon an hr, there are just a few times when last minute changes are needed. I've just always wondered how other brewers would adjust to account for this. Thanks again

 

[unseenat17]

All good up to using the word "percentage". Boil-off isn't actually a function of percent of wort, it's a fixed rate based on boil vigor and surface area of the vessel. Ie, if you boiled 6 gallons and lost a gallon per hour, it'll still be a gallon per hour if you start with 8 gallons...

Cheers!

Oh..duh. Thanks for the correction!

 

[zacster]

Yea, I'd say the timings should be from the end of the boil, so your 5 minute addition should still be 5 minutes from the end, no matter how long your boil. In your situation though you already added them, if you have some extra add it at 5 minutes, if not, oh well. Just live with it.

You could I guess dry hop if you can still find hops nearby on the same day. If you have to order them though it may take too long.