My BJCP Exam Results

... are in and I'm officially a certified BJCP judge! A year of studying the style guidelines, tasting many many hundreds of classic examples, and writing an ungodly number of practice scoresheets paid off. I scored in the eighties, which is good enough to take me up to a national judge but not quite what I'd need to hit the master level. I'm thrilled to have scored that well.

I owe a great debt of thanks to one James Lewis who organized and taught the class, as well as my classmates from CHAOS and Square Kegs for keeping it fun. (Sampling 5-10 beers every three weeks under the critical lens of the style guidelines gets a little harder than one might expect...)

Onward to the summer competition circuit and to the two competitions Square Kegs will be putting on this year: Überbrew and Winterbrew!

Being A Coffee Nerd Taught Me Something About Brewing

Usually it's the other way around. The silly amount of random brewing knowledge I've built up tends to inform a lot of the food science and chemistry stuff I think about.

But this week I was making the first starters of the season for a Scottish 80/- which Square Kegs (my homebrew club) is brewing this weekend for an awesome event called Beerfly Alleyfight put on by Haymarket Brewery. It's part of Chicago's Craft Beer Week and is a simply phenomenal event. But I digress.

We've been making pour-over coffee at my office in a Chemex for a while now. (If you haven't been bit by the coffee bug, you might not want to read on. It's the preferred brewing method of hipsters and snooty coffee snobs.) The standard Chemex rig consists of a burr grinder, the chemex and a scale on which to both weigh out your beans and then for weighing out the hot water.

The important part here is that the Chemex looks a lot like an Erlenmeyer flask and it sits on a gram scale throughout the whole brew process.

For some reason it never occurred to me to use the same scale I use to measure my DME for starters to measure the water. I'd just measure up to what looked like about the right volume based on the markings on the flask. But now that I'm in the habit of using the Chemex, I used the scale for measuring the water. I feel like a moron for never having done that before. (It's dead simple to convert between the two. 1mL = 1 gram of water.)

It just goes to show that you can always draw inspiration from other places in your life.

I Don't Believe In New Year's Resolutions

... but this year I'm making some brewing resolutions for the 2014 season. Jeremy and I are good brewers. We win medals in competition. We can generally turn out consistent beers from batch to batch. The number of hours I've devoted and the amount of educational material I've devoured keep mounting.

But we're still not great. We don't often take a category gold, and we've never won a best in show. Hop character is still hit or miss in our beers. The occasional batch is a clunker and I'll dump it or pawn it off on unsuspecting friends during one of our "family" dinners.

And so, I want to get better. So over the winter I've ruminated on and off about our process and what we can change for the positive. Here's the list:

1. Make our starters earlier and bigger. I tend to do most of the yeast management and sometimes those poor little critters only get 24-36 hours of time to warm up and get ready to chew through some sugars. We also only have two 2000mL flasks and one stir plate so they end up splitting time on it. We're going to buy a couple of 4 liter flasks and a second stir plate to really handle the pitches we need for lagers and higher gravity beers.
   
2. Make the same beers until we get them dialed. We've brewed our way through a good number of the recipes in Jamil's Brewing Classic Styles. This has been wonderfully informative on the ways different ingredients play in different styles. But the only beer we've ever scored in the 40's on was the ginger wheat recipe I've brewed over and over and over again through the years. Slowly tweaking the recipe every time has gotten it to the point that it's really balanced, drinkable and has a huge amount of flavor.
   So we're going to make beers we've made before, that we can drink ten gallons of over the course of the summer and not get sick of. And we're going to make them until we get it right.
   
3. Take (even better) notes. I'm a big fan of brewing software. (We use Beer Alchemy. I'm partial to it because it's a well built Mac UI and it's dead simple to use despite having almost all the complexity you could want.) We already take detailed notes and monitor fermentation. But I'm talking about taking it to the next level and having a brewer's log detailed enough to track mash thickness, sparge rates, actual pH vs target pH, mash efficiency, evaporation, target vs actual attenuation, etc.
   There are a lot of little variables which don't lend themselves to tracking easily in the software but can (or at least I think they should) tell us something about the beers that turn out great vs. the ones that don't. (The fact that I'm spending a fair amount of time talking quality assurance with my buddy Gary who is damn close to opening up Panic Brewing just might have something to do with this.

So we'll see if it's made any difference by the end of the summer... It definitely can't hurt.

Original Gravity vs. Plato / Brix

Oddly enough, the homebrew world and the professional brewing world use two totally different units to measure dissolved sugar content in our wort and our finished beer. Homebrewers use Specific Gravity and most pros use Plato. Why you may ask? I don't really know. Probably just 'cuz that's what I started with'.

Both give you a means to measure potential alcohol content and actual attenuation. Both are fairly straightforward to read and to use. So why should anyone care about the difference? Well, they mean different things and have different unit qualities.

Specific gravity (S.G.) is the ratio of the density of a sample liquid (wort) to the density of water. Because wort has dissolved sugars and a few other compounds in it, it's more dense than water. As our little microbial friends do their job and convert that sugar over to alcohol, which happens to be even less dense than water, the SG of the solution drops. There are some well-established formulas / calculators to help you with the exact math, but the scale provides a very simple approximation. Under most normal fermentation conditions, the part after the decimal point is pretty close to what your finished alcohol content will be.

So for a 1.050 SG beer, fermented to 1.012 FG (75% attenuation), you get 5% alcohol. (.05 = .05)

For a 1.080 SG beer, fermented to 1.019 FG (75% attenuation), you get 8.01% alcohol. (.08 ≈ .0801)

One usually measures SG with a hydrometer. It uses a specifically calibrated weight and a scale to measure the relative density of the liquid. Since the pre-fermentation solution has a higher density than plain water and alcohol has a lower density than water, it's straightforward to calculate the finished alcohol percentage. (Technically we lose some CO2 out of the airlock, but it's not enough to matter.)

Brix or Plato is the percentage of dissolved sucrose by weight in a solution. As I mentioned above, technically this is an approximation in wort because not all of the sugars all sucrose and not all of the dissolved solids are fermentable. Regardless, it's a pretty damn good estimate. (Brix and Plato are technically very slightly different scales, but for all practical purposes they can be used interchangeably.)

1 degree brix equals 1 gram of sugar dissolved in 100 grams of water. Also pretty simple, right? So for those same beers we talked about, a 1.050 OG is equivalent to 12.5 plato (or 12.5% dissolved sugar) and a 1.080 OG beer is equivalent to 19.3 plato (or 19.3% dissolved sugar.)

Typically you'd use a refractometer to measure Brix. It uses a known change in the refractive index to measured the percentage of dissolved sugar. However, alcohol's different refractive index makes it basically impossible to use a refractometer to measure finished gravity. It's just not the right tool for that job.

A Brief Summary of Hop Chemistry

It seems that the whole craft beer community is obsessed with hops. Consumers go batshit crazy over beers hopped and dry-hopped with the latest and greatest proprietary poster children of breeding programs. (Three Floyds Zombie Dust blew the doors of for Citra, and as of late Mosaic is the darling of the brewing world.) Hop Contracts are the de facto norm for any and all "in-demand" hops and for most anything that's commonly used in the states. Good luck getting your hands on Amarillo, Citra, Mosaic or Simcoe in quantities of a pound or more.

Most everyone reading this blog knows that hops impart bitterness, aroma and flavor into beer. But the commonly accepted knowledge amongst homebrewers about how this actually works can be summed up in a couple of sentences: Adding hops with high alpha acid content at the beginning of the boil contributes to bitterness. Adding hops toward the end of the boil and through dry hopping enhances aroma and flavor. 

Thankfully, the greater brewing community (largely commercial brewers and academics the like of Dr. Charlie Bamforth, with a substantial contribution from Stan Heironymus and the Brewers Association) is starting to peel the layers back on the actual chemistry at work here and share that knowledge.

Let's talk about bitterness first: Alpha acids are indeed the compounds which contribute to bitterness in finished beer, but they don't do it directly. During the boil (in the presence of heat and kinetic energies) they change their structure slightly through a process called isomerization, which simply means that the atoms in the molecule re-arrange themselves and exhibit different chemical properties.

Adhumulone, cohumulone, and humulone are the three distinct compounds which comprise the majority of the alpha acid content in a hop.

Adhumulone generally represents a minority of the alpha acid content and its contribution to bitterness is not deeply understood.

Cohumulone and humulone make up the majority of alpha content. Noble hops tend to have a higher ratio of humulone to cohumulone and as such cohumulone was considered less desirable and to impart a "harsher" bitterness. As such, it's common to see a humulone / cohumulone ratio or percentage cohumulone content published in hop data. However, newer high-alpha hops have been developed which have higher cohumulone content without any "harshness".

Interestingly, the isomerized alpha acids contribute to both foam stability and provide anti-bacterial properties on top of contributing bitterness to the finished beer.

On to aroma and flavor: Hops also contain a small percentage (by weight) of essential oils which are almost entirely responsible for their flavor and aroma contributions. There are numerous oil fractions present in hops, but four in particular make up the majority : caryophyllene, farnesene, humulene and myrcene. Each of the oil fractions has different aroma and flavor profiles and volatilize at different temperatures, although they'll all volatilize off during an extended boil. As such, late kettle, flame-out / whirlpool and dry-hopping all emphasize the aroma and flavor contribution by allowing these essential oils to stick around. 

Caryophyllene adds a spicy, herbal and/ or woody character similar to humulene when boiled. Its effect on flavor when fresh is not well understood. Interestingly, it is one of the chemical compounds identified as contributing to the spicy character of black pepper and is also found in substantial quantities in Basil, Canabis, Cloves, and Oregano. Caryophyllene oxidizes quickly and as such its aroma / flavor contributions will drop off quickly in finished beer.

Farnese is is typically only found in significant quantities in noble hops. Its fragrance has green, woody, vegetative notes with hints of lavender. Flavor-wise, it adds the essence of herbs and organic wood-like offsets. Oxidation degrades its essence rapidly, and storing in air tight refrigerated packaging increases its storability.

Humulene  is thought to lend the distinctive "noble" character to noble hops; most varieties traditionally considered noble are high in humulene, while many bittering hop varieties have very low levels. It contributes woody, earthy, and herbal aromas and flavors. The noble character is strongest when the hops are used in dry hopping or late hop additions; if boiled for longer periods, humulene lends the finished beer an herbal or spicy character. Oxidation degrades its essence rapidly, and storing in air tight refrigerated packaging increases its storability. Humulene does have a higher boiling point relative to the other oil fractions and will contribute more aroma and flavor if used earlier in the boil.

Myrcene contributes a green, herbaceous, citrusy, resinous aroma often associated with "American" or "fresh" hop character. It is highly volatile and loses much of its aroma when boiled. It is also found in Cannabis, Lemongrass, Mangoes, Thyme, and Verbena. Myrcene is highly volatile / unstable and as such will provide maximum flavor contribution when used as a late / dry hop and in beer consumed when fresh.

There's a lot of chemistry at work here. (Frankly, far more than I grok at this point.) But it's safe to say that there's a lot more to adding bitterness and flavor to our beer than just grabbing a couple packages of pellets at the homebrew shop and adding them at the beginning and end of the boil. 

If I had to guess, one could dive in to the oil profiles of individual hops and start to determine what flavors and aromas they'd contribute when used at different points in the process. (More to come soon on that...)