Beginner Tips : Wort Aeration

Oxygen is the enemy. This is hammered into the brains of all homebrewers. We're told of the importance of not splashing beer too much during the mash, not splashing the beer at all when racking from the primary fermentor, leaving as little headspace as possible in secondary fermentors, blanketing the beer with CO2 when kegging, etc. Oxygenating beer at these stages can lead to stale, "cardboard-like" flavors, and can decrease the beer's shelf life after packaging.

Of course, there is one time when you WANT to oxygenate your beer: when the wort has been cooled, right before you pitch your yeast. While fermentation is anaerobic (meaning oxygen is not required), yeast DO require oxygen for reproduction. So, you want to have some oxygen available in the just-cooled wort for the yeast to use for producing the cell walls for their offspring. The idea is that, at the very beginning of fermentation, the yeast use up the oxygen, reproduce to higher numbers, and then actively ferment the sugars in the wort into alcohol and CO2, making beer.

If we don't add enough oxygen into the wort before fermentation begins, there are a lot of problems that can result. Common ones (and I've had my share of these) include:

• Under-attenuation and stuck fermentations
• Slower fermentation starts, and therefore a higher likelihood of infection
• Longer fermentation times
• Yeast stress and off-flavors
• Lower viability for re-used yeast generations

In the excellent book, "Yeast: The Practical Guide to Beer Fermentation", by Chris White (of White Labs) and Jamil Zainasheff, the authors conclude (from various studies) that 8-10 ppm is the ideal oxygen concentration to have in wort for optimal yeast growth. As homebrewers, there are basically three methods available to use to aerate our wort:

1) Shaking the fermentor - Every homebrewer has used this method at some point. And a lot of veteran homebrewers STILL oxygenate their wort by shaking. In fact, up until my Maine Beer Company Zoe clone a few weeks ago, this is how I've aerated every single past batch. How long you shake, and how much headspace you have in the fermentor will determine how much oxygen you get into the wort. With lots of both, "Yeast" reports that a maximum of 8 ppm of oxygen can be achieved. However, keep in mind that with a 6-6.5 gallon fermentor, and ~5.5 gallons of wort, you don't really have a lot of headspace to work with when you're relying on shaking.

2) Aquarium pump with sintered stone - I haven't used this method, but know some people that do. From what I've heard, it can take quite a while to fully oxygenate wort this way (up to 30 minutes). As with shaking, greater than 8 ppm of oxygen cannot be achieved no matter how long you run the pump.

3) Pure oxygen - The preferred (and most expensive) route, and the only way to get up to (and beyond) 10 ppm of oxygen. This is the method I used for the Zoe clone, through the "Oxygen Aeration System" through Williams Brewing. This involves a stainless steel aeration stone and wand, tubing, and a regulator for a standard small oxygen tank (that you can purchase at most hardware stores). Simply sanitize the stone and wand, drop it in your fermentor, turn on the oxygen till you see bubbling for 30-60 seconds, and the yeast is ready to be pitched.

Of course, there's few homebrewers out there who will spend the large sum of money to buy equipment to measure just how MUCH oxygen they're getting into their wort. Regardless of which aeration method you use, you're guessing at what you're putting in. Even though the Williams system has the regulator to control the oxygen flow, you don't know for sure where to turn the regular knob so that you're getting, say, 1 L of oxygen per minute.

Do you have to worry about getting too MUCH oxygen in your wort? Definitely not if you're shaking or using an aquarium pump. If you're using pure oxygen, it's still probably not a worry. However, "Yeast" does say that really high amounts of pure oxygen can result in "high levels of fusel alcohols, increased acetaldehyde, and other flavor problems". This would be difficult to do accidentally on a homebrew level, however; you'd have to have the oxygen turned on for a significantly longer time to get really high levels that would be detrimental to your beer.

When about aerating really high-gravity beers? It's simply stated in "Yeast" that with beers with OGs higher than 1.092, aeration methods other than pure oxygen simply won't do. In fact, the authors suggest that for all beers with an OG above 1.083, aerate TWICE. That is, before pitching the yeast, and then another dose of oxygen 12 to 18 hours after pitching (this allows the yeast one cell division). This second dose was shown in a study to help speed up fermentation speed and attenuation.

Generally speaking, if you're brewing a low-to-mid-gravity beer, you're probably ok to aerate by shaking, if you put a lot of effort and a good amount of time into it. But when you're brewing bigger beers, or lagers, and you really want to ensure you're getting the right amount of oxygen -> healthier, happier yeast -> better beer, you're better off using pure oxygen. I finally made the move to pure oxygen because I've had many batches (especially "bigger" beers) where I've had trouble hitting my target FG, and now that I've consumed over 60 types of my homebrew, I'm picking up on off-flavors that could be attributed to under-aeration. I felt this was a small investment to make for healthier yeast and (hopefully) better beer.

Tasting : Hicken (Hill Farmstead James clone)

This has to be a record for me, posting tasting notes for a beer less than 2 weeks after it's been bottled! Of course, this should always be the case when I'm reviewing a beer that has a big hop-component, but a) I sometimes get a bit lazy, with other things going on, and b) I'm hesitant to rush into it, until I'm sure how I feel about a beer. But with this, a clone recipe of the Black IPA, James, from Hill Farmstead that I brewed last month, I wanted to get this down immediately. I opened the first bottle only 5 days after it had been bottled, and it blew me away.

This beer was all I hoped it would be, and more. As I mentioned in the recipe post, it's been over two years since I tried James in Vermont, so I wasn't really sure what to expect - whether I successfully cloned it or not. I'm assuming that I HAVEN'T (based on the huge success of Hill Farmstead's beers), unless I completely fluked out. Whatever, this beer is delicious! Definitely one of the best beers I've brewed, and one of the best Black IPAs I've had, commercial or homebrew. The hop aroma is HUGE, flavor is fantastic, and it's creamy while still finishing fairly dry. The roast/chocolate character is JUST there, but the hops clearly dominate - exactly what, I think, a good Black IPA should have.

Of course, the first time I brew a batch smaller than 5 gallons (with all the hop sludge and such, I bottled just about 3 gallons), it would result in a great beer. I will definitely brew it again. There's a slim chance I'll be in Vermont in the fall, so maybe I'll be extra lucky and get to try some HF James again. In the meantime, if you're looking for a great Black IPA recipe, I recommend giving this one a try. Thanks again to Mitch Steele for writing the IPA book that provided the bulk of this recipe!

Appearance: Poured with a moderate-large, light tan creamy head that shows excellent retention; eventually fades to 1/2-finger. Sticky lacing left on the sides of the glass. Body appears black at first glance, but when held to the light you can see it’s more of a very dark brown. Opaque.

Aroma: Strong aroma of citrusy, dank hops. There’s a bit of chocolate in the background, but the hops stick out the most, with a hint of pine in there as well. As it warms, the alcohol comes through slightly.

Taste: There’s just a small bit of roast/chocolate that hits at first, but like the aroma it gives way to a big hop flavor. While you can definitely get the citrus in there, I’d say the dank aspect comes out ahead. Finishes with a firm, moderate-high bitterness. Creamy and easy-drinking.

Mouthfeel: Medium-bodied, with moderate, maybe even moderate-low carbonation.

Overall: Very delicious. I think the first bottle I had three days ago actually tasted and smelled fresher, however. Too early to really tell that, though, as I’m not 100% sure the beer is done conditioning. I’m ok with the carbonation where it is, however, and I think I prefer it this way. The more I drink this, the more impressed I am with it... certainly can’t remember if it’s even close to James, but I’m really happy with it overall.

Tasting : Rising Tide Daymark clone vs. Daymark

It's been a long time since I've done a tasting of an attempted clone beer of mine and been able to actually compare it to the commercial beer. To make things even better, the "Born on" date of the Daymark bottle was March 6, 2013... and my clone was bottled March 13th, so they're pretty close in age. Obviously, doing a taste test of two American Pale Ales that are 2 months old isn't ideal, and I'm totally to blame for that. I've had the Daymark on hand for at least a month now; I just completely dragged my feet about opening both beers at the same time, taking notes, etc. Anyway, on to the comparison!

Appearance: Pretty darn close. Both beers are quite pale, maybe a light gold color, with moderate-large, white sticky heads with great retention. I'd say my clone is a touch lighter in color, with slightly better clarity.

Aroma: Both beers have a pleasant fruity, citrus aroma. My clone is stronger in the hop department, while the Daymark has more of a malty sweet background, and more rye presence as well. Don't get me wrong, the Daymark is still hoppy... I'd say it's better balanced. The clone beer's aroma also has a bit more "dank" character that I expect from Columbus hops now.

Taste: In general, like the aroma, the clone is hoppier... the citrus slaps you in the face a bit more, even at two months old. The Daymark is maltier, and the rye definitely sticks out more. I'd say the Daymark also has a SLIGHTLY higher bitterness in the finish.

Mouthfeel: Very similar... my beer has just a touch more carbonation.

Overall: I'm going to go with 85-90% cloned here. If I brewed it again, I would back off on the dry hop some... maybe cut it down to 1 oz each of Centennial and CTZ. I'd also increase the rye malt to 15%; since Nathan said they use various local sources of rye malt, it could also simply be a manner of taste differences between their rye malt and mine. Not sure. A tasty beer, but not quite up to the caliber of the real thing!

Brewing a Maine Beer Company Zoe clone (No. 3 in the Maine Beer Clone series)

 

When deciding on the third clone for this, my "Maine Beer Clone series" (previous entries were Oxbow's Freestyle #5 and Rising Tide's Daymark), I continued to have a lot of options. Sorry to beat a dead horse by saying that Maine has a lot of awesome breweries, but it's the truth. Despite all this, however, picking what was next was actually very easy... in fact, I would have done this beer even earlier, but I wanted to wait until I thought I had enough info to take a real shot at it. The brewery is Maine Beer Company, and the beer is Zoe, an American Amber Ale in the U.S. West Coast sense - bigger and hoppier than your "typical" Amber.

When I took my first beer-trip to Portland, ME in June of 2009, Maine Beer Company had basically just started as a professional brewery. Started by brothers Daniel and David Kleban, they only had one beer at the time, an American Pale Ale called Spring Peeper. This was actually the first Maine beer I had on this trip, and I was blown away by it. It was, and still is, one of the best APAs I've ever had... super-hoppy in a very citrusy way, bitter but not overly-so, with a supporting malt background. This beer is still available; the name has just been shortened to "Peeper". Since then, every beer that they have released has been awesome, in my opinion... and a lot of other beer drinkers would agree with me. MBC has grown quite a bit since 2009, and they just moved to larger headquarters in Freeport.

The second beer that MBC released was their self-described, "Happy, Hoppy Amber", named Zoe after the daughter of one of the Klebans. At 7.2%, the beer pours a dark red color, has a really nice caramel malt background (with a touch of chocolate), and a pretty large hop presence, citrusy and piney. A delicious beer. I've had a lot of the "bigger" Ambers over the past few years, and Zoe is still probably my favorite of them all. Like I said, I love all of the MBC beers I've tried, and would be happy trying to clone any of them... but I haven't brewed an Amber in a while, and Zoe is the perfect one to try.

I had actually emailed MBC a couple of years ago about help with a Zoe clone, but the only reply I received directed me to the info on their website. The site DOES actually say what the starting gravity is, and what malts and hops they use... enough to start with, but I wanted a bit more, if possible. About 6 months ago, however, I stumbled upon a clone recipe for Peeper on one of the homebrew forums online. Obtained from Dan Kleban, it was very detailed. It was noted that the recipe was given to the homebrewer back when MBC was just getting started, and that it was more difficult to get this much info out of the brewers now. So, I sent a direct message to the person who had posted it, and he sent along the email address that Dan had replied from.

Knowing that emailing a brewer and just saying, "Give me the recipe for your beer, please" is not the way to go about it, I emailed Dan and told him what I was thinking for the recipe. Here's what I originally came up with:

"~42% each 2-row and Marris Otter, 5% each Victory and Munich, 2.5% each Crystal 40 and 80, and maybe 1-2% Chocolate malt. Mash 152 F. Columbus for bittering, Centennial and Simcoe @10 min, lots in the whirlpool, and a good dry-hop of each as well. Maybe 65 IBUs? Ferment with a neutral American Ale yeast at about 68 F."

Now, as I mentioned, I had the list of ingredients from the MBC website. I based the amounts on the Peeper description and the corresponding clone recipe online... basically, they seem to list their grains in decreasing amounts. I knew that Zoe has a touch of chocolate flavor, but nothing severe, so I figured the Chocolate malt was more just to darken the color of the beer a bit. I guessed on the hop combinations and "amounts", but knew (again, from the Peeper recipe) that Dan does large flameout additions; Zoe may not be as hoppy as Peeper, but it can be pretty darn close. Also, Zoe is bitter but not super-bitter, so I thought ~65 IBUs was a fair guess.

I waited for awhile and never heard back. I sent the email a second time, about a month later, just in case, but still never got a reply. Then, about a month ago, I sent a message to MBC through their Facebook site, and they gave me Dan's email... which was different from the one I had been using! Whoopsie. I emailed the new address, and Dan replied almost right away:

"You are remarkably close. Mash a little cooler, 150. Simcoe bittering. Keep Columbus in the late hop additions and DH."

Ok, maybe not as much info as the Peeper recipe, but hey, I had something to work with now!

So, I basically had the grist decided, since Dan didn't suggest any changes there. When developing the hopping schedule, I kept it fairly simple. I went with a bittering charge at 60 minutes of Simcoe (despite my reservations, using a valuable hop like Simcoe for bittering!) to ~36 IBUs... the rest of the bitterness would be from late additions. Originally I had planned on one flavor addition, and a whirlpool addition for a hop steep, but I decided to go with 1/2 oz each of Simcoe, Centennial and Columbus at both 10 and 5 minutes. I really have no idea if MBC uses equal amounts of these hops for flavor and aroma, but I know that they DO use equal amounts of late-addition hops for Peeper, so I chose to follow this lead. Two large flameout additions of all three (one AT flameout for a 10-minute hop steep, the other when I turned on the chiller), and a decent-sized dry-hop to finish off.

Not much left to deal with, here. I DID make a couple of water adjustments. I have no idea what the Portland, ME water analysis looks like, and I didn't bother trying to figure it out, since I would have to find out exactly what MBC does to their water (if anything) when brewing. However, Mike Tonsmeire of The Mad Fermentationist provided a water profile he calls "San Diego - Hoppy" on his blog, from when he was helping Modern Times develop recipes for their year-round beers. A hoppy Amber was one of the beers that Mike helped develop, and I really liked the look of the water profile, so I adjusted my water to meet those targets (basically, increasing calcium, chloride, sodium, and sulfate to moderate levels).

In terms of yeast, "neutral American Ale yeast" means, for us homebrewers, anyway, either Wyeast 1056 American Ale, White Labs WLP001, or US-05 for dry yeast. I suspect that MBC uses a strain with better attenuation than any of these yeast strains, mainly because of the numbers listed on their website. For example:

Peeper: OG 1.047, ABV 5.5%... so, the FG would have to be ~1.005, which is 90% apparent attenuation
Zoe: OG 1.064, ABV 7.2%... FG must be ~1.009; 86% average attenuation

Their other hoppy beers follow along these lines. However, Wyeast 1056 lists an attenuation as between 73 and 77%, which is a lot lower than upper 80s. I personally would have preferred to use 1056 here, but the pack my LHBS had was over two months old and would have required a two-step starter to get the yeast numbers I needed, so I ended up using about 1.5 packs of US-05, rehydrated. I've never had attenuation with US-05 approach 86%, so I really doubt I'll get this beer down to 1.009. We'll see.

This brew marked the first time in a while that I have purchased new equipment. I finally broke down and made a move into wort aeration that doesn't simply involve shaking the carboy. Williams Brewing, an online home oxygen aeration system for sale that's pretty cool - it's simply a stainless steel aeration stone, some tubing, and an oxygen regulator that you hook up to one of those small oxygen tanks that you can buy at hardware stores. However, it's a sure-fire way to get the required amount of oxygen into your wort... shaking can only add so much, and this becomes more of an issue with higher-gravity beers. I plan on posting about wort aeration in the near future, so more on that later.

With a trip to Portland planned (hopefully) for next month, it should be pretty easy for me to find another bottle of Zoe to take back to compare to my beer; this is great, considering the beers I've been trying to clone lately that aren't available nearby at all. I really like this style of beer, so I'm hoping to make tweaks to the recipe over time until it's close to the real thing.

Thanks to Dan Kleban for his help with formulating the recipe!

Recipe targets: (6 gallons, 72% efficiency) OG 1.064, FG ~1.009, IBU 66, SRM 15, ABV ~7.2%

Grains:
2.77 kg (41.75%) Canadian 2-row
2.77 kg (41.75%) Maris Otter
372 g (5%) Munich
372 g (5%) Victory
168 g (2.5%) Crystal 40 L
168 g (2.5%) Crystal 80 L
100 g (1.5%) Chocolate malt

Hops:
Simcoe - 28 g (12.9% AA) @ 60 min
Simcoe - 14 g @ 10 min
Centennial - 14 g (9.9% AA) @ 10 min
Columbus -14 g (14.5% AA) @ 10 min
Simcoe, Centennial, Columbus - 14 g each @ 5 min
Simcoe, Centennial, Columbus - 21 g each @ flameout, 10-minute whirlpool
Simcoe, Centennial, Columbus - 21 g each when started chiller
Simcoe, Centennial, Columbus - 28 g each dry-hop for 7 days

Misc.: 1/2 tab Irish moss @ 5 min

Yeast: US-05, 1&1/2 packages, re-hydrated

Water: Fredericton city water, carbon-filtered; 3 g Epsom Salt, 4 g table salt, 6 g Gypsum divided between the mash and sparge water

- Brewed on May 5th, 2013, by myself. 60-minute mash with 20.5 L of strike water, mashed in a bit high at  151 F. Sparged with ~4.75 gallons of 168 F water for final volume of ~7.25 gallons in the kettle.

- SG a touch low at 1.051 (target 1.052). 60-minute boil. Chilled to 65 F in about 20 minutes with immersion chiller. Poured ~5 gallons into Better Bottle. OG 1.063. Aerated wort with 60 seconds of pure O2. Pitched yeast and set BB in laundry room sink, ambient temp about 68 F.

6/5/13 - In AM, airlock bubbling q 2 seconds or so, temp 64 F. By PM, temp had increased to 68 F, and airlock was bubbling every second.

7/5/13 - In AM, activity has increased, airlock bubbling probably twice per second; temp had increased to 72 F. By PM, starting to slow down at every second, temp still at 72 F.

8/5/13 - Steadily slowing throughout the day, bubbling every 5 seconds by the evening, temp dropped a bit to 70 F.

23/5/13 - Added dry hops into primary.

30/5/13 - FG 1.013. Bottled with 120 g table sugar, aiming for 2.5 vol CO2 with a max temp of 72 F reached.

25/6/13 - Tasting notes from a week ago, compared to the real Zoe... came out really great, very similar to Zoe.