Hop Utilization (A Geeky Take)

One of the lessons it really took me a while to learn is how different hop additions truly affect the finished beer. I started to really get into craft beer (which at the time was still colloquially referred to as "microbrew") shortly before I started brewing. So by the time that I was really starting to experiment with recipes and deviate from kits, I'd developed a palate for hops. Furthermore, I was in a purely experimental mode and brewing without doing a ton of research and definitely without the aid of brewing software to help me calculate the effects of recipe changes or additions.

As I've researched more, started to use software and take measurements religiously, I've dialed in my understanding on a few parts of recipe formulation. This post is about hops and bitterness. All of the calculations herein are performed using the Rager formula. (Apparently this is less accurate for full-volume boils than Tinseth, but it's what I've been using and it's what the guys at the brewing network use. Since most homebrewers probably aren't using lab equipment to accurately measure IBU's, we're just looking for a consistent way to measure.)

The IBU scale ranges from 0-100. According to most sources, you really can't discern bitterness past 100, but you will pick up additional hop aromas from late boil additions or dry hops once you've hit 100 IBU.

There are five variables in the Rager formula which affect bitternes: wort volume, wort gravity, alpha acid %, hop mass and addition time. I held the wort volume and wort gravity constant and ran some numbers for both this post and my own curiosity. The results were interesting and pointed out a few things I hadn't fully realized before.

(The table I used to create the graph is here.)

The conclusion I'd already come to by using brewing software and digging in to styles is that it doesn't take much of a bittering addition to max out one's taste buds. A 1 oz charge of bittering hops is really all you need for an IPA or any other highly bitter beer. Much beyond that and you're just wasting hops.

One thing I didn't realize is that the utilization (according to Rager) for a 90 minute boil is almost exactly the same as a 60 minute boil. So don't bother extending your boil time for higher bitterness. (Use it for wort concentration on high gravity beers or DMS reduction, but those are two separate posts.)

The other thing which I dug into is the affect of a flame-out addition. Based on some other sources, the extraction of bitterness from hop additions happens at temperatures above 158F. As such, your flame-out or late additions may end up contributing more bitterness than aroma if you're not cooling your beer quickly. (I noticed a substantial difference in the level of hop aroma I got this summer when I incorporated a proper wort chiller into my process.)

Brewing and Engineering

My post from yesterday referenced the strong correlation I've noticed over time, but here are some more concrete examples of a very strong correlation between brewing and engineering. (I picked up Brewing Better Beer last week and started reading it in earnest today. Turns out Gordon Strong is a software engineer by training as well.)

Jamil Zainisheff (Software Engineering) : Author, Ninkasi Award Winner, Brewery Owner, Radio Host
John Palmer (Metallurgical Engineering) : Author, Radio Host
Gordon Strong (Software Engineering) : Author, 3x Ninkasi Award Winner, BJCP Grand Master Judge, BJCP President
Matt Brynildson (Chemistry) : The most award-winning brewmaster in America

I'm a software engineer by training, as is Jeremy and the other guy I brew with on a semi-regular basis. Anyone else out there happen to notice this or have other good examples from the commercial world?

*As an engineer I'm clearly obligated to acknowledge that this is far too small of a sample to be statistically significant. However, these are all guys who are at the absolute top of their game and all happen to have a math / science background.

DIY'ing Brewing

I think that there's a pretty strong correlation between being an engineer and enjoying homebrewing. Part of the fun (at least in my book) is getting to build your own gear. Some of the nicer commercially produced stuff out there is pretty expensive but not all of it is as nicely made as the Blichmann stuff... So since I'm kind of cheap, have a pretty substantial collection of tools, and love making stuff, I've built or modified a decent amount of stuff at this point which I use on a regular basis. There's something particularly satisfying about not only making beer but making beer with a brewery you've assembled partially by hand.

To date (in rough chronological order) I've DIY'd the following:

• Wort Chiller (Bad design, ultimately replaced with a commercially made immersion chiller which I have plans to Jamil-ify this winter)
• Kegerator (With disconnects for Corney and Sankey kegs)
• 10 Gallon Rubbermaid cooler mash tun
• 5 Gallon Rubbermaid cooler HLT / sparge tank
• Hose-friendly water filter
• A Keggle

Over the next couple of weeks I'll post more in-depth articles on some of the above. 

The Evolution of a Beer Lover's Palate

Over the summer, we opened a new restaurant at my day job. After years of pushing for a better beer list, I finally met with a measure of success at this location. We held a couple of staff tastings with a certified cicerone to educate our servers and bartenders on what they were selling to our customers.

One of the things which jumped out at me was that the beers I liked the most got the most confused reactions from our staff. However, the cicerone had a nice nugget of wisdom: an appreciation for bitterness is the last thing to develop for most beer drinkers. I think that this is true, with one addition. Appreciation for bitterness is second to last, with an appreciation for sour beers being the last.

I personally started with the heavily fruited (Lindeman's being the most widely available here in Chicago) lambics, but tried a true gueze at some point a few years ago and appreciated how different it was. I've slowly been drinking more and more sour beers as of late and really growing to appreciate the complexity of something you have to slow down and sip. The old-world Belgian examples have a lot to offer, but there are some american breweries doing excellent work in this Genre. (Jolly Pumpkin is a Michigan-based small brewery who does exclusively sour, barrel-aged beers and happens to probably be my favorite thus far.)

There's even five gallons of sour cherry brett-fermenting lambic slowly aging away in a dark corner of my basement right now...

I was inspired to post this after reading this article.

Back to the Basics : The Extract Experiments (pt 1.)

So, after a summer of intense brewing I'm going to test a hypothesis this winter. Since I'm in Chicago and it gets way too damn cold and snowy to brew outside, I'm going back to extract with steeped grains. This might seem a bit odd, even given the environmental constraints of the midwest, but there's a purpose. Jamil often talks on The Brewing Network about how important good fermentation is to the end result of a beer. I want to put this to the test and see if we can brew some amazing extract beers this winter using a stovetop, a ten gallon megapot, a wort chiller (which I need to add a garden hose fitting somewhere indoors for), and proper fermentation technique.

The hot side process will be dramatically less complex than what we've been doing all summer, but the fermentation side will stay exactly where it's at now. (Yeast starters with proper pitching rates, oxygenation, temperature control, finished up with cold-crashing and 1-2 weeks of lagering depending on the beer.)

We're starting off with an Imperial IPA and a Mexican Hot-Chocolate infused stout. (Foreign Extra.) Results on these beers and a few more will follow soon...

Citra IPA (Zombie Dust Inspired) Wrap Up and Tasting Notes

This beer was in the fermentor for twelve days (five or six very visibly active days, after which I raised the temp on my controller by four degrees to help the yeast do their cleanup work), cold crashed and on the yeast for another week, and then transferred to a keg and lagered for another week.

After a lot of reading this summer and fall (particularly Jamil Zainisheff and Chris White's Yeast book), I've switched to a process that relies more on temperature than on racking to achieve clarity in my beers. It seems to be working pretty well...

So on to the fun part - drinking the beer! 

Appearance: Straw colored, leaning ever so slightly towards copperish. (Thank you melanoidin malt.) Bright white head which sticks around and leaves a defined lacing down the side of the glass.

Aroma: I love Citra. Seriously. The nose on this one is resiny, overlaid with the tropical fruit you pretty much only get from Citra. Negligible malt on the nose.

Taste: Starts out with the same pine and resin and note you get on the nose, after which you move to the residual malt sweetness and some slight bread / toast notes and then finishes out with that tropical fruit funky bitterness. The first couple pours had some distinct sulfury yeast flavor from the Wyeast 1056 which I've picked up on other batches, but that's disappeared either on account of cold and time or just being pulled out in the early pours.

Mouthfeel: Light body and lively carbonation. 

Drinkability: Win. For a beer that came in at 7.5%, there is almost no aggressive alcohol character or other hints that it's a big beer. The low finishing gravity and the dry finish make this a dangerously session-able beer.

I'll post pictures shortly and do a side by side of the Wyeast and White Labs batches soon!

Epic Blow-off

Last weekend I brewed two five gallon batches of Russian Imperial Stout with Jeremy. Both recipes were monster beers (more on that in a future post) with target original gravities over 1.100. The brew day was largely uneventful - no boil overs, no stuck mashes / sparges.

We wrapped up brewing around 5pm, filled up the second better bottle with roughly 5.5 gallons of the bigger of the two beers, oxygenated for 45 seconds off of a disposable tank, and pitched a starter of WLP004 (Irish Ale.)

I mistakenly put the temperature control probe on the other beer, which was slightly lower in starting gravity and pitched with WLP001 (Cal Ale.) The typical blow-off rig I've been using at this point is a drilled universal bung with 5' of 1/2" OD tubing into a growler half-filled with Star San.

It probably should've been cause for alarm when I checked on the batch three or four hours later and the big batch was already showing signs of active fermentation. Alas, I was just excited to see it bubbling away.

This is what I found the next morning when I went to check on it... I don't have the fancy vinyl sticky numbers on the side of the better bottles, but I'm guessing we lost about a gallon of beer out through the blowoff hose. That black pool of liquid the carboys are sitting in is potentially delicious monster stout I had to drain out onto my basement floor. The temperature on the smaller beer was stable at the controlled 68F, but the big one had risen to 72F.

Needless to say, after spending a half an hour cleaning this mess up, I moved the growlers out into buckets outside of the freezer and proceeded to witness still more blow-off.

I've never used the foam control products in a fermentation, but does anyone out there have any suggestions for how to avoid this scenario? My thoughts were to use a bigger diameter blow-off hose, add fermcap, or leave a lot more headspace on a big beer like this one...

WLP001 v Wyeast 1056 Results

The citra IPA Jeremy and I recently brewed was the first batch I've actually oxygenated vs simply aerated. After reading Yeast by Jamil Zainasheff and Chris White, I decided to invest the few bucks in a mostly proper oxygenation setup in order to get my fermentation that much more optimal. We brewed for a ten gallon yield, split the batch in half and pitched starters of WLP001 and Wyeast 1056 into two separate fermentors. Each 5 gallon better bottle got a 30 second shot of pure oxygen through a 5 micron stone. Both 2 liter starters were treated identically with yeast nutrient and splitting time on the stir plate.

Fermentation took off pretty quickly for both (an expected outcome) but over the course of fermentation, I experienced a level of attention from WLP001 which was a completely unexpected outcome.

OG on this beer was 1.065 and the target finishing gravity should have been around 1.016. On this batch the WLP001 made it all of the way down to 1.008. This puts the attenuation rate at 85% instead of the typical 75%. The Wyeast ended up right around 1.016. Jeremy got the WLP batch, so I haven't had the opportunity to do a side by side of carbonated, conditioned beer, but my preliminary tasting indicated that the WLP version was more neutral and thinner than the Wyeast version. The latter had some of the faint sulfury character I've picked up on the last few batches we've fermented with Wyeast 1056.