Designing/converting recipes for 'ultra-short' boils?

I recently converted the Amarillo Pale Ale recipe (Amarillo Pale Ale - Beer Recipe - American Homebrewers Association) to be a 30 minute boil all DME recipe using ideas from these two posts: https://www.homebrewersassociation.org/forum/index.php?topic=29885 & https://www.homebrewersassociation.org/forum/index.php?topic=29617.0 .  The results came out well for the 1st iteration. It was fun to see the color come out as described in the 1st topic.  So a ‘thank you’ to those who offered advice in those topics!  On to my question.

If you brew DME/LME with ‘ultra-short’ boils (15 minute ?, 5 minute?, heat just enough to pasteurize?), how do you adjust the hop rates when converting from a recipe with a more typical hop schedule?

Apr 2018 edit. two links for IBU calculations: IBU Calculator - Diversity Methodology (FWH, Boil and Whirlpool bitterness): https://www.homebrewersassociation.org/forum/index.php?topic=30046.0 ; An Analysis of Sub-Boiling Hop Utilization: An Analysis of Sub-Boiling Hop Utilization | alchemyoverlord

late Nov 2018 edit: see also Basic Brewing Radio, Nov 1, 2018

Math. Software and web based recipe platforms can do the work for you. Shorter boil = more hops.

For my 20 min. boil recipes I increase the bittering hops by 50%.

Look in how to brew. There you will find all the hop utilization equations.

What’s the motivation for the short boils?  Is the extra half an hour of time worth using double the hops?  There’s still all the time of getting it up to a boil, as well as chilling.  I use the boil time to sanitize my fermenter and clean up my other gear.

Because homebrewers in general boil off way to much (commercial systems average ~5%), and the TBI index is off the charts.  So a shorter boil evaporates less generally and most people notice better beer.  But in reality you could just lower your evaporation and achieve the same thing with 60.

Gotcha.  One big change I’m noticing with the Grainfather is the vastly reduced boiloff.  I’m still dialing the system in, but that was a surprise.  I usually brew outdoors over propane.  I wonder if there is a reduction in boiloff due to the increased humidity and ambient temperature when brewing indoors?  I’m guessing that’s a factor, but that’s hard to quantify.

I do AG batches with a 20 min. mash and 20 min. boil.  I up the bittering hops by 50% to compensate for the short boil.

And I thought I was daring by going down to 45 minutes.

Sure, man.  Brew what you like, however you like to brew it.  Sorry for questioning your motivations.  Peace out, homey.

Sorry if I contributed to thread drift.  I didn’t mean any disrespect with my question about your motivation to brew with shorter boils.  It’s just something I’ve never done in my 14 years of brewing, and I wondered what the motivation was.  I appreciate learning from the experience of others on this forum, and part of that is feeling free to ask questions.

I’m glad shorter boils are working for you, but did you consider this?  If you did longer boils, you would have more time to up your post count with the Song Titles thread.  Sweet.

Some help needed in England please. I have started doing 30 min mash and 30 min boil for my stove top BIAB and partial mash brews, purely for time saving, though I like the idea of more hops later, maybe I should do 20/20. It’s early days and I’m struggling with IBU accuracy, I don’t know how to calculate the effect of adding hops to the kettle after the mash, and 15-20 minutes before the boil is reached, and the period after the boil when the wort is above 80C/176F. I estimate this to be about 15 minutes - I cool in the kitchen sink. It’s like isomerisation gets the full 60 minutes or so. My first 30/30 brew was much more bitter than planned, as isomerisation was presumably taking place before and after the boil. A 60 minute boil takes out most of the acids so didn’t present this pre/post boil problem, to anything like the same extent.

I could add the first hops to the kettle at boiling point to solve that end of the equation. At the other end, should I time the period it takes me to get to 80C and add that time to the hop calculations? Because there is clearly still a fair amount of acid being converted. Thanks.

Thanks Kat - I’ll see what I can glean from those.

I mostly brew partial mash beers inside in the summer when its in the 90’s outside. I’m using a 30 minute mash and a 15 minute boil as it keeps steam production low and doesn’t heat up the house like long boils. Plus the beer still tastes great! Just need to use more hops.