Thursday, 24 July 2014

Brewing a Hefeweizen

I don't know about most of you homebrewers out there, but I (usually) keep very-detailed records of my exploits in this hobby of ours. Aside from using brewing software (Beersmith) to come up with my recipes and enter brewing data, I have a binder filled with notes, details and tasting notes on every beer I've brewed since my first brew in November, 2009. I also have my planned brewing schedule, inventory, future brew ideas, etc. stored there. I even keep this binder with me at work, for when I have free time and want to go back to check things. Maybe a bit overboard, yes, but hey, it helps sometimes!

A couple of months ago, I was looking over previous beers I've brewed, and was struck by the fact that I haven't brewed a Hefeweizen (aka Weissbier) in 3 years. I was honestly shocked; a German wheat beer, Hefeweizen has to be one of the perfect summer-beer styles. Spicy and fruity, refreshing and light-drinking, the best ones have a perfect balance of banana and clove aromas and flavors, backed up by the presence of wheat, with high carbonation. Sounds great for this hot weather, doesn't it? A lot of commercial breweries brew a Hefeweizen of their own this time of year, and there's many German examples that are widely available... if you haven't already, get out there and give some of them a try. You'd be surprised how much they can differ. For my money, you really can't get much better than Weihenstephaner's Hefe Weissbier.

I brewed a Hefeweizen my first two summers of being a homebrewer; in fact, my second beer was an all-extract Hefeweizen that somehow won a gold medal in the German Wheat and Rye Beer category in the ALES competition in 2010. The past two years, however, I concentrated on another great summer style, Witbier (like this one from last year, hopped with Belma). As much as I love a good Witbier, I thought it was definitely time to revisit the Hefeweizen style. 

Hefeweizen is a beer style that has a deceptively-simple recipe, yet can be difficult to brew a great example. If you look at the majority of recipes out there, you're going to find a grist of at least 50% Wheat malt (German law actually states that a beer labeled as Hefeweizen must have 50% or more Wheat malt) and 50% Pilsner malt. And that's usually it. You don't want Crystal malt in there, or anything else, really. Sure, some people probably throw in some flaked oats or torrified wheat or something similar, to increase the body/creaminess of the beer, but you don't want it to be heavy-bodied (medium-light to medium is what you should aim for) or sweet, so keep it simple. I've had great results with the 50/50 ratio of Wheat malt and Pilsner, so I chose to stick with it again this time, with a small addition of Acid malt for mash pH purposes. If you're feeling ambitious and nostalgic for the old ways, you can do a decoction mash; for me, I only have so much time to brew, and I've had good luck with a single infusion mash as usual, so that's what I'll be doing here.

For hops, I'm aiming for a classic Hefeweizen, which means basically no hop aroma or flavor. So, a simple light addition of a noble variety (e.g. Hallertauer, Tettnanger) early on in the boil to add a bit of bitterness, and that's all.

What really makes or breaks a good Hefeweizen is the fermentation of the beer; while a Belgian Witbier relies on the addition of coriander and citrus peel to provide at least some of its spice and fruit character, Hefeweizen gets all of the banana and clove components from yeast. Yeast strain, yeast health, and fermentation temperature are extremely important. Yes, they're ALWAYS important in any beer style, but given that the overall recipe is usually so simple for Hefeweizen, they're even more important than usual. Let's dissect each component...
  1. Yeast strain - There are several commercial strains available for brewing Hefeweizen, but I've always used the same one - Wyeast 3068 Weihenstephan Weizen. It's readily available at my LHBS, but more importantly, it really is a great yeast. Supposedly the same strain (basically) as what the Weihenstephaner brewery uses for their beers, it does a fantastic job of providing both the banana esters and clove phenols necessary for a great Hefeweizen. The balance between the two is generally pretty good, however, you CAN steer it in either direction... whether you mean to or not. Which brings us to the next two points...
  2. Pitching rate - Like in almost 100% of cases, you should make a yeast starter when brewing a Hefeweizen. However, overpitching yeast can actually result in LESS esters being produced, which means the banana character will be diminished, and the clove character (the phenols) will be more apparent. If you like more clove than banana in your Hefeweizen, this is one way to achieve that result. Conversely, underpitching will produce more esters/banana character. I won't get into the exact science, but the harder yeast have to work, the more esters that will be produced as a result. A well-balanced Hefe is preferred by most, so use a yeast pitching calculator like the one at Mr. Malty, and aim for what it recommends. How much is too much? I don't have the experience to tell you, which is why I recommend sticking with a calculator, at least as a starting point. After that, you can start tweaking your process to find what makes the best Hefeweizen for you.
  3. Fermentation temperature - Generally, the thought is that the warmer the fermentation temperature, the more banana esters that are produced, and the less clove character you get as a result. Conversely, the lower you ferment, the less banana you get. However, in Jamil's Brewing Classic Styles, he highly recommends fermenting in the low-60s F, saying that these temps will give you the best-balanced Hefeweizen. I followed this suggestion with my first attempt, and fermented my second Hefeweizen at about 68 F. Both came out pretty well, I thought, with both seeming quite balanced to me. If you have excellent fermentation control, go ahead and try the low-60s; however, for this time of year, if you don't have rigid control over your fermentation temperature, try to aim for 67-68 F and not go too much over, or the banana character may be a bit overwhelming.

Something else you need to remember when brewing this style of beer - there's no need to use any fining agents at all. If you look back at most of my recipes, you'll see I always add a half-tablet of Irish Moss (aka Whirlfloc) near the end of the boil, which helps the clarify a beer. Hefeweizen is one of the few styles where you actually WANT a cloudy beer; in fact, when pouring one, you want to rouse the yeast in the bottle and pour that in your glass as well. So, no Irish Moss, Whirlfloc, gelatin, etc. when brewing this style.

Also, just a warning if you use the Wyeast 3068. I can't speak for the other Hefeweizen yeasts out there, but 3068 is pretty active. Leave yourself a good amount of headspace in your fermentor (Wyeast goes as far to recommend 33% of your fermentor), or at least use a blow-off tube. There will likely be a huge krausen on this beer; I hadn't had any problems in the past, but for this brew day, fermentation started quickly and got a bit violent, and I lost a bit of beer to overflow. Luckily, no explosions with beer on the walls and ceiling, but still, losing beer is not a good thing, ever!
I was very slow in getting this post out, seeing that the beer was brewed a month ago, so look for the tasting notes relatively soon. Remember with this style, it is meant to be consumed fresh!

Recipe targets: (5.5 gallons, 75% efficiency) OG 1.049, FG ~1.011, IBU 11, SRM 3.7, ABV ~4.9%

2.1 kg (49%) Pilsner malt
2.1 kg (49%) Wheat malt
80 g (~2%) Acid malt

Tettnang - 20 g (4% AA) @ 60 min

Misc.: 68 g rice hulls, added to the mash

Yeast: Wyeast 3068 Weihenstephaner Weizen (PD May 9/14, with a 1.4 L starter)

Water: Fredericton city water, carbon-filtered; 3 g calcium chloride added to the mash

Before the near-explosion

 - Brewed on June 24th, 2014, by myself. 50-minute mash with 13 L of strike water, mashed in at target temp of 152 F. Mashed-out for 10 minutes with 6.25 L of boiling water. Sparged with ~4.5 gallons of 168 F water for final volume of ~7.25 gallons.

- SG a bit high at 1.038 (target 1.037). 90-minute boil. Began chilling at flameout, brought temp down to 64 F after 20-25 minutes. Final volume ~5.5 gallons. OG on target at 1.049. Aerated with 75 seconds of pure O2, pitched decanted yeast starter. Placed BB in laundry sink with cold water.

- Despite the fairly-low pitching temperature, airlock activity began about 12 hours after pitching. By the next morning, the temp had climbed to 70 F and the airlock was full of krausen and about to blow, Replaced it with sanitized foil; was able to replace the airlock by that evening. The next day the temp had dropped back to 66 F, and everything had settled after 4 days from pitching.

- 16/7/14 - FG 1.012. Bottled with 190 g table sugar, aiming for 3.5 vol CO2 for 5 gallons, max temp 70 F.

- 28/8/14 - A little late, but posted the tasting notes. This came out just how I wanted to, basically; refreshing, nicely balanced... the perfect summer beer.