Monday, August 29, 2011

Micro-IPA with Nelson Sauvin

First wort hops waiting for the boil.Don't get me wrong, I love big hop-saturated double IPAs, but is all of that alcohol a necessary part of a great hoppy beer?  There are some great session strength hop-bombs like Hill Farmstead Edward, but I'm talking even lower than its 5.2% ABV.  So light that you could drink half a gallon and still ingest less alcohol than there is in a single pint of the last DIPA I brewed.  Inspired by the description of Mikkeller's Drink'in the Sun, I set my sights below 2.5% ABV for this "Micro-IPA" (the least alcohol of any beer that I have brewed).

After draining the first runnings for my Riwaka hopped Hefeweizen, I reinfused the mash with 178 F sparge water, stirred, and let it sit for 45 minutes.  I suspect that this long/hot sparge-rest facilitated additional starch to sugar conversion favoring alpha amylase's production of unfermentable dextrins (a positive for a small beer).  Ideally a low gravity beer should be brewed as a no-sparge (with a hot saccharification rest) to maximize body and malt flavor, but I couldn't say "no" to free wort.  After the boil the original gravity measured a paltry 1.030 (after correcting for temperature).

OG reading 1.030, including the temperature adjustment.I hopped the low-gravity wort with a combination of Nelson Sauvin and Amarillo.  The only beer I'd brewed with Nelson before was restrained (.75 oz total in 3 gallons), but I enjoyed the white wine and pine aromatics that this New Zealand variety imparted.  Blending with Amarillo adds complementary citrus character while mellowing some of the aggressive notes.  The early boil addition provided moderate bitterness (going for the IBUs of a hoppy pale alem let alone DIPA, would detract from the drinkability).  With 6.75 oz of aroma hops I wasn't quite as aggressive as I have been with the late boil and dry hop additions, but I was still heavier handed than many recipes I see for IPAs.  In my experience the ratio of gravity to IBUs needs to be taken into account for balance, but I don't think the same is true for hop aroma.

After fermenting with American ale yeast the gravity only dropped to 1.014 (the same as my Pliny the Younger clone).  Alcohol is lighter than water, so the 1.028 residual extract of that 10.5% ABV behemoth was almost as high as the original gravity of this featherweight.  As a result of the lower residual extract this beer tastes much drier than a highly attenuated West Coast IPA, despite barely crossing 50% apparent attenuation.  This is an example of why final gravity and attenuation are not reliable indicators of how sweet a beer will be when evaluated in isolation. 

In addition to being able to enjoy two pints after work and still cook dinner, the other benefit of a low gravity IPA is that it has a quick turnaround (allowing you to enjoy the fresh/raw hop aroma).  Alcohol is responsible for extracting some of those great aromatic compounds from dry hops so I'm interested to see how well the keg hop addition works.  This beer is already being force carbonated, so I should be able to post a tasting this week or next.

Nelson Jr. Micro-IPA 

Recipe Specifics
Batch Size (Gal): 5.25
 Total Grain (Lbs): 15.75
Anticipated OG: 1.030
Anticipated SRM: 6.2
Anticipated IBU: 36.0
Brewhouse Efficiency: 26 % (74% including first runnings)
Wort Boil Time: 75 Minutes

63.5% - 10.00 lbs. German Wheat Malt
31.7% - 5.00 lbs. American Pale "2-row" Malt
4.8% - 0.75 lbs. CaraVienna

0.75 oz. Nelson Sauvin (Pellet, 10.30% AA) @ First Wort.
2.00 oz. Nelson Sauvin (Pellet, 10.30% AA) @ 0 min.
1.00 oz. Amarillo (Pellet, 10.00% AA) @ 0 min.
2.75 oz. Nelson Sauvin (Pellet, 10.30% AA) @ Keg Hop
1.00 oz. Amarillo (Pellet, 10.00% AA) @ Keg Hop

0.50 Whirlfloc @ 15 min.
0.50 tsp Yeast Nutrient @ 15 min.

WYeast 1056 American Ale/Chico

Water Profile
Profile: Washington DC

Mash Schedule
Sacch Rest - 45 min @ 154

Brewed 8/6/11

Infused the mash for the Riwaka Wheat Beer with 6 gallons of sparge water at 178 F (added 6 g of gypsum to the water to boost the sulfate, and cut it with 2 gallons of distilled) and let sit for 45 minutes before vorlaufing and draining.

Second runnings, 6.5 gallons of 1.024 Really low gravity, interested to see if the fact that it is second runnings leaves it too thin or not.

Chilled to 65 F, pitched one fresh pack of yeast (no starter) and left to ferment at 63 F ambient.

Three days later raised the ambient temp to 65 F.

8/18/11 Fermentation appeared finished, so I racked to a keg with the dry hops and hooked up to CO2, and left in the kegerator to carbonate at 40 F.  Gravity only down to 1.014 (2.1% ABV, and not much more than 50% apparent attenuation, but that may not be a bad thing for this one).

9/1/11 Great hot-weather hop-bomb love those Nelson and the Amarillo was a great pairing.

Monday, August 22, 2011

Hoppy (Riwaka) Hefeweizen

Flameout Riwaka hop addition.I've always been a homebrewer who is inspired to try the next thing (ingredient, technique, combination etc...), the batch I'm most excited about is usually the one I'm about to brew.  As a result, I have tended to avoid rebrewing the same sorts of beers on a regular basis.  However as time goes by I'm starting to get the desire to dial in the recipes for a few of my favorite batches.  The Hoppy Hefeweizen I brewed last summer was so good (the combination of fruity/spicy yeast and citrusy American hops), that I had to brew something similar again this year.

Despite how much I enjoyed that original batch, I still made two major changes for the rebrew (I couldn't help myself).  I simplified the mash to a single infusion; for a regular hefeweizen I'm willing to go through the time/effort of a decoction mash, but with a load of aroma hops I don't think the subtle complexities are worth the additional time and effort (but we shall see).  I also switched the hopping to Columbus (from Perle) for bittering, and Riwaka (from Cascade and Amarillo) for aroma.  Riwaka is a relatively new variety from New Zealand that reportedly has a strong citrus character similar to Cascade (the "tastes like chicken" of the hop world).  Anything in that area should be a good addition to the banana-forward-fruitiness that the the Weihenstephan strain will contribute.

Strained out hops post-boil.At the moment I have two other beers fermenting/carbonating that feature Southern Hemisphere grown hop varieties as well (a 2.25% "IPA" with Nelson Sauvin, and a double IPA with Galaxy).  The Oceanian varieties are supposed to have a big fruit character including tropical, citrus, and white wine notes (missing the pine that American grown hops tend to contribute). It has been interesting to experiment with new hop varieties, especially with the current scarcity of similar American varieties until the fall harvest.  I ordered the hops from an Australian homebrew shop a couple months ago, with shipping it worked out to just under $4 an ounce.  If I'd waited a few weeks longer many of the same varieties began showing up at some American homebrew shops for half that price (although I got mostly whole hops and I've only seen pellets imported).

I've got high hopes for this beer as a refreshing late-summer drinker.

Riwaka HoppyWeizen

Recipe Specifics
Batch Size (Gal): 5.25   
Total Grain (Lbs): 15.63
Anticipated OG: 1.054 
Anticipated SRM: 6.0
Anticipated IBU: 47.1
Brewhouse Efficiency: 48 % (74% including second runnings)
Wort Boil Time: 75 Minutes

64.0% - 10.00 lbs. German Wheat Malt                
32.0% - 5.00 lbs. American Pale Malt (2-row)  
4.0% - 0.63 lbs. CaraVienna

1.00 oz. Columbus  (Pellet  12.00% AA) @ 60 min.
3.50 oz. Riwaka (Whole, 5.50% AA) @ 0 min.
3.50 oz. Riwaka  (Whole, 5.50% AA) @ Dry Hop

0.50 tsp Yeast Nutrient @ 15 min.

WYeast 3068 Weihenstephan Weizen

Water Profile
Profile: Washington DC

Mash Schedule
Sacch Rest - 60 min @ 154   
Mash Out - 15 min @ 168

Brewed 8/6/11

Cut filtered tap water with 2 gallons of distilled to lower carbonate, added 4 g of gypsum to boost sulfate.  

Crush didn't look great, but ended up with 6.5 gallons of 1.046 runnings (first runnings only).  Sparged to make a second runnings beer (Nelson Jr. IPA)

Chilled to 65 F and pitched an inflated pack of yeast (no starter), but it was less than a month from manufacture.  Left at 63 F ambient to ferment in a large bucket.  Three days later raised the temp to 65 F.

8/20/11 Racked to a purged keg, put into the fridge at 34 F for a week of cold conditioning before dry hopping.

8/28/11 Moved out of the fridge.

9/3/11 Dry hopped in a mesh bag weighted down with marbles.

11/9/11 Turned out nicely, good balance of citrus hops and banana yeast. Took longer than expected to get here though, too yeasty initially.

Thursday, August 18, 2011

Blackberry Flemish Red - Final Tasting

I always have a hard time bringing myself to open the last bottle of any beer I've brewed, but this bottle of Blackberry Flemish Red was harder than most since it was the last of the first batch of sour beer I brewed.  Sure, technically I still have a bottle of the same beer without blackberries that I'll be opening soon (but the version with fruit has always been superior). It seemed appropriate to get a picture of this beer next to the circa 1895 ginger beer bottle I bought last weekend while looking for a radiator at Community Forklift.

2006 seems like forever ago, but it also feels like I've been brewing sour beers for much longer than five years.  Since that fateful first batch I've brewed close to 50 more and in the process found a hobby (and niche) that I love. In that time brewing has taught me a lot more than just how to brew, but that discussion will have to wait for its own post.

Blackberry Flemish Red next to a Pitt & Norrish Ltd bottle.Blackberry RodenTons

Appearance – The red/brown body has just a hint of the purple it had in its youth. It has a slight haze despite serving at cellar temp. The thin off-white head quickly dissipates to a ring circling the edge of the glass.

Smell – The aroma is still remarkably fresh with notes of citrus, cherry/berry, damp oak, and faint caramel malt. There is a low-level floral character that I associate with age, but no cardboard oxidation. It will be interesting to see if the part of the batch without blackberries fared as well (fruit contributes powerful anti-oxidants that delay staling).

Taste – It had been long enough since I opened a bottle of this that I couldn't remember exactly how it tasted; the first sip brought me back. The sourness is quick and sharp upfront (still seems predominantly citric/malic from the fruit rather than lactic from the bugs) followed by a touch of acetic on the swallow. The fruity/funky Brett adds a great deal of complexity. The blackberries mingle with the balsamic character of the sourness to provide a great deal of depth to the natural fruit character of the beer without overwhelming the other flavors. Good balance, with a slight sweetness still hanging on.  The finish has a slightly strange, although not unpleasant, vanilla-oak character that I don't remember.

Mouthfeel – Medium body with vibrant carbonation. A bit more sparkle than I usually aim for, but I'd say it is still under 3 volumes and has been remained stable.

Drinkability & Notes – Glad the beer in this bottle survived the heat of the last few summers down in DC with me. Sorry to see this batch gone, but I think it is better to open it now to enjoy rather than holding onto it until after it ages too much.

Monday, August 15, 2011

Sour Braggot (Red Wine Barrel)

You can really see how much yeast/trub was left in the barrel after bottling.Sour beer is by its very nature unpredictable.  To make one you must rely on multiple strains of wild yeast and bacteria that haven't had the benefit of several thousand years of domestication as brewer's yeast has.  After our first red-wine-barrel-aged-beer, a Flemish Red, took one year to ferment we expected a similar performance from the following beer into the barrel.  After the red was bottled we refilled the barrel with Belgian Single (a recipe cribbed from Russian River Redemption/Beatification) without washing or even completely draining it. That was 20 months ago.  We were hoping to bottle sooner, but it took longer than expected for adequate sourness to develop.  A good reminder that you can't put sour beer on your schedule, you have to be patient and wait until the flavor is right.

I'm surprised how much color the wood still had after holding beer for almost three years.As always, we used a high capacity postal scale to precisely measure each five gallon bucket of beer we pumped out of the barrel.  For our priming calculations we assume .4 volumes of residual carbonation at bottling (about half of what a non-barrel-aged-beer retains), which has given us good results on our previous batches.  In this case we wanted 2.6 volumes of carbon dioxide, which worked out to 5.9 ounces of corn sugar for each 5 gallon bucket (plus a small dose of rehydrated wine yeast).  One gallon of my share went onto two pounds of over-ripe white nectarines, which should be an interesting experiment.

Before refilling the barrel we gave it a quick rinse with cold water to remove the spent yeast and trub left from the first two beers.  I've heard several professional brewers suggest that a high temperature rinse is crucial for preventing acetic acid production in subsequent beers, but I think their issue is a result of the days or weeks that the barrels sit empty before refilling (Acetobacter thrives in unwashed air-filled barrels).  In our case the barrel sits empty for less than an hour, and as a result we have yet to experience a vinegary beer.  After rinsing our bourbon barrel before the most recent fill we have not noticed the sourness taking any longer than usual to develop (the microbes live far enough into the wood that it almost impossible to kill all of them even with scalding water).

I really had to push the limit of my system to make 10 gallons of wort.A couple of months ago, after determining that the Single was finally ready to bottle, the group decided that for the third beer into the barrel we wanted a recipe that would be a bit more unusual.  The winning idea was a golden braggot with honey malt and carapils.  I've already heard some grumblings on my Facebook and Twitter profiles that the ~25% honey we are adding isn't enough to qualify it as a braggot, but I haven't found a reliable set of guidelines that put a firm number on the amount of honey required for the "style."  My first honey sour beer had a similar percentage of its fermentables from honey and has plenty of waxy/floral honey character in the aroma.

With all of the beer racked into the barrel we still had a few gallons of head-space, but that was no real problem as we still had to add ten pounds of light honey (clover and wildflower) which will most likely be followed by another ten pounds.  In past batches we have had a member contribute fresh wort to the barrel to give the microbes a dose of simple sugars to work on, but in this case the honey filled that role.

Bottling assembly line in action.Wine Barrel Braggot

Recipe Specifics
Batch Size (Gal): 10.25
Total Grain (Lbs): 26.75
Anticipated OG: 1.071
Anticipated SRM: 4.6
Anticipated IBU: 24.4
Brewhouse Efficiency: 66 %
Wort Boil Time: 90 Minutes

78.5% - 21.00 lbs. German Pilsener
3.7% - 1.00 lbs. CaraPils
3.7% - 1.00 lbs. Honey Malt
14.0% - 3.75 lbs. Honey (added to barrel)

1.50 oz. Galena (Pellet, 8.50% AA) @ 90 min.

WYeast 1214 Belgian Ale

Water Profile
Profile: Washington DC

Mash Schedule
Sacch Rest - 60 min @ 158
Mash Out - 15 min @ 165

Brewed 7/10/11 by myself

Collected 9 gallons of 1.064 runnings.

Chilled to 70 F, pitched onto a yeast cake from Summer in Brussels. Added 2 gallons of chilled water. Shook to aerate. Left at 65 F to start fermenting. Solid fermentation within 18 hours.

7/24/11 Racked to two kegs, just about full on both of them. Topped off with CO2 and left to age until barrel day.

8/7/11 Racked into the red wine barrel. Rinsed out with cold water to remove yeast trub before refilling.

Thursday, August 11, 2011

Belgian Summer Ale Tasting

Belgium has gained a reputation for high alcohol beers, aggressive sours, and other weird, challenging, and complex creations.  However they also brew some great session ales: Wit, Belgian Pale, and Abbey Single.  These are the traditional everyday drinking beers of Belgium (or they were before the growth of pale lager brewing). This Belgian Single was just a quick batch meant to build up enough yeast for 10 gallons of braggot for out third wine barrel fill, but I still wanted to do something interesting with it.  Inspired by the first batch of Russian River's Redemption (apparently Vinnie's favorite bottling of any of his beers to date) I added a small amount of White Labs Brettanomyces bruxellensis to some of the bottles right before capping.

I wanted to do a tasting of this one young so I could find out how quickly the Brett is going to make a noticeably flavor impact.  To make sure my brain doesn't get in the way of my tongue I decided to do a blind triangle test to see if there was an appreciable difference between the two versions of the beer.  I'll be repeating this test every couple months to see how quickly the small amount of Brett I added at bottling impacts the flavor (and carbonation) of the beer.

From left to right samples: #1, #2, #3.
Summer in Brussels

Appearance – All three have a similar bright yellow body with thin white heads. #3 has slightly worse head retention than the other two, and #1 is hazier.

Smell – Yeast character dominates in all three aromas.  Sample #1 and #3 have similar fruit and spice aromas including some banana. #2 is more spice (clove) heavy with a reduced fruitiness. #3 has more honey aromatics than the other two, but it is slight.

Taste – All of the glasses have a similar crisp pilsner malt backbone and just a hint of herbal hops.  None of them taste overtly funky or Brett-like at this point. #1 has a bigger yeast character than the other two, I'd suspect it was the second pour off of one of them. #2 is slightly cleaner than the other two, less fruity, more balanced. 

Mouthfeel – Sample #2 is a bit thinner than the other two, with marginally higher carbonation. 

Drinkability & Notes – All three of the beers are enjoyable and refreshing, but at this point if forced to choose I would go with #2. I'll guess that #2 is the Brett spiked bottle, and the other two are both the clean one. There are slight differences at this point (more carbonation, less body, and less fruit make me think the Brett is starting to work), but nothing major.

After checking I was correct that #1 and #3 were from the same bottle, but I was wrong on which one. Surprisingly the non-Brett-spiked beer was more carbonated, lighter, and fruitier. It will be interesting to see how this changes in the next few months.

Friday, August 5, 2011

The Great Souring Experiment

So many carboys of sour beer...The first Friday of every month marks “The Session” when participating beer bloggers all post their take on single topic.  Getting bloggers to write about the same thing is a great way to promote discussion and the exchange of ideas. I’ve never joined in before (I tend to be anti-blogger-social), but with August’s sour beer topic it seemed like a good time to give it a shot. This blog delves into brewing sour beers more than occasionally, so I was torn on exactly what to write about.  An overview of brewing sours didn't seem interesting or specific enough (not to mention that I've already posted one).  While homebrew bloggers participate in The Session, it is predominantly bloggers who focus on craft beer, so I wanted to do something that even people who don't brew would find interesting.

While stripping labels from a few cases of bottles, I started thinking about how much beer I have to bottle over the next few weeks and what I’ll be brewing to fill all of those emptied carboys.  While working on my book I've researched all of the different techniques that brewers have come up with to turn beers acidic, but I've had a hard time comparing the results because each brewery sticks to just one (or at most two) methods.  Comparing results between breweries has its own problems because of the large variation in microbe selection, aging temperature, grist, aging vessel etc...  So I dreamed up:

The Great Souring Experiment!

Produce a series of sour beers using different methods, while controlling for as many variables as possible by using the same ingredients, microbes, and equipment to isolate the character that each method imparts. 

1. Inspired by Russian River (Temptation): single infusion mash, ferment with a Belgian ale strain, fine and crash cool to remove the yeast, pitch Brettanomyces, followed a few weeks later by Lactobacillus and Pediococcus.

2. My standard: same wort as #1, but pitching all of the yeast and bacteria into the wort at the same time.

3. Inspired by The Bruery (Marrón Acidifié): same wort as #1, but with 100% Brett/Lacto/Pedio fermentation (no brewer's yeast).

4. Inspired by Ithaca (Brute): replace ~14% of the malt with acid malt, ferment with an English ale strain, followed by secondary with Brett.

5. Inspired by Pizza Port (Mo' Betta Bretta): Sour the wort pre-boil with Lactobacillus, followed by fermentation with 100% Brett.

6. Inspired by Cambridge Brewing (Cerise Cassée): Sour mash in a carbon dioxide flushed mash tun, primary fermentation with an ale strain, and finally secondary with all of the microbes.

Almost all American breweries that publicly discuss their method use some variation on one of these six. Trying all of these methods would provide new tools for making sour beers, as well as insight into how the same microbes behave under a variety of conditions.

I'd suggest using a pale base beer to let the microbes' character shine. The recipe could be as simple as 80% pilsner, 20% flaked wheat to 1.050 with ~15 IBUs of noble hops added near the start of the 90 minute boil.  To avoid variations due to microbe selection/viability use the same pure cultured microbes for each batch (avoiding the variability of bottle dregs).  I'm thinking of using Wyeast Lactobacillus and Pediococcus for sourness and their Brett bruxellensis and Brett lambicus for funk.  All of the batches should be aged at the same temperature and in the same type of fermenter.  At packaging they should each receive the same amount of carbonation.

Final Thoughts:
I'd be interested to hear if anyone has other methods to suggest for comparison.  I did not include spontaneous fermentation (even though it is gaining in popularity, and my first American Lambic tastes great after just four months) since it wouldn't be the same microbes.  Including a duplicate of one of the first three methods, switching the single infusion to a turbid mash to show what it actually adds to the final character.  Using one gallon jugs for fermentation would allow for splitting the wort from one mash in several ways to reduce the amount of brewing required.

Ideally, brew all of the batches in quick succession so they have similar ages for the more accurate comparison. After 12-18 months bottle some of the beer straight and use the rest to find how the characters meld and mesh. I'm not sure whether I'll have the time or effort to pull this off, and even if I do it will be a few months before I can fit them into my schedule.  Interested to hear if other people think it would be worth the effort, or if anyone has tried something similar.

Tuesday, August 2, 2011

Upcoming Class: Homebrewing Locally

The last hop on the vine is always the king of the bine.I'll be teaching a class about brewing with local ingredients at Mountain View Farm in Purcellville, VA on Sunday August 14th from 2-5 PM .  The class will cover making beer with ingredients you'd be more likely to find at a farmers market than a homebrewing store.  During the session I'll be demonstrating several techniques while brewing a beer that includes locally grown grain, fruit, and hops. The recipe (even the style) are still to be determined because the farm has not told me exactly what ingredients they will provide.

During the lulls in brewing I'll be discussing how to cereal mash, make herbal teas/tinctures, use wet hops, capture wild yeast, and prep fruit.  There should also be plenty of time to answer questions and tailor the topics to what people are most interested in.  I'll be providing a few samples from my cellar to illustrate the results as well.

It is a perfect time for this class since many brewing ingredients are starting to come back into season here in the Mid-Atlantic.  Over the last few weeks I have picked the first of my hops, and bought sour cherries, blackberries, white nectarines, and methley plums to add to various batches.  It would really be great though if I could find a reliable source for local malt (off topic, but has anyone had a chance to try brewing with anything from Valley Malt? I had a solid beer from Wormtown Brewing that used their malt and had an interesting grainy character). 

If you are interested in attending the class, it is $25/person or $40/couple.  To reserve a spot contact Shawna  at [email protected].  If you either aren't in the area or can't make it then I'll be posting a full report on the recipe and how the class went in a couple weeks.  I may be running an intro to homebrewing class at the same farm sometime this fall, but more details on that will have to wait a couple months.

8/4 There are only seven (of twenty) spots left, if you are interested in coming please sign up soon.

8/11 The class is now sold out. I also found out I'll be using some wheat and local peaches, should be a good combo with the homegrown hops.  Looking forward to seeing everyone there.

Here is a post with some information about what was covered in the class, and the recipe for the beer we brewed.

Monday, August 1, 2011

Who Makes the Best Lambic?

My cellar is short on Lambics at the moment, but still had a Drie Fonteinen and a Boon.Cantillon - 58%
Drie Fonteinen - 13%
Lindemans - 5%
Girardin - 5%
Hanssens - 5%
Boon - 4%
Oud Beersel - 2%
De Cam - 1%
Mort Subite - 1%
Belle Vue - 0%
St. Louis - 0%
Tilquin - 0%
Timmermans - 0%
(321 Votes)

After last month's poll on which American brewer makes the best sour beers, it seemed only logical to follow-up with a poll about Belgian Lambic producers.  Much like Russian River Brewing in the previous poll, Brasserie Cantillon beat all comers handily in this one.  I think a big part of their dominance is their great beers (obviously), but their reputation for being both purists and innovators as well as their wide distribution area doesn't hurt.  While I love both Cantillon's Gueuzes and fruit Lambics, they are only my second favorite producer. 

Overall I don't think Cantillon has quite the depth and balance of the Lambics from 3 (Drie) Fonteinen.  Armand is probably the most consistent blenders, I'm hard pressed to remember an off bottle of Drie Fonteinen (on the other hand I've had a couple less than stellar Cantillons).  It is hard to compare these two, Cantillon is a brewery that produces all of their own wort while Drie Fonteinen is a blender that (primarily) ferments wort that other breweries sell them.  It is an advantage to outsource wort production to several great brewers because it allows you to get a range of characters that is difficult to obtain from only one brewery (especially when you rely on a single production method).

I think what really sets these two apart from the rest of the brewers and blenders is their willingness to experiment and market.  Some of the other straight Gueuzes are at least as good as Cantillon Classic Gueuze or Drie Fonteninen Oude Gueuze, but in some cases that is all that gets exported.  I won't say that I have enjoyed every one of the experimental batches and special releases that I've been lucky enough to taste from Drie Fonteinen or Cantillon, but many of them have been great (like the ones at the Lambic Summit), and even those that haven't been perfect are enlightening. 

The rest of the producers make some great Lambics (amazingly all of them received at least one vote).  Some of my favorites include Girardin Gueuze 1882 (Black Label), De Cam Oude Gueuze, Hanssens Oude Kriek, Boon Mariage Parfait (especially the 2004 bottles that you can still find randomly), and Oud Beersel Oude Gueuze.  I even like Lindemanns Cuvee Rene and St. Louis Gueuze Fond Tradition if I can't get my hands on anything else (especially since they are less expensive).

In a lot of ways it seems like people are all too happy to shell out $15 for the new sour from some random American brewery, that they forget just how good even the mediocre Lambic producers can be.  If you haven't picked up a random bottle of Gueuze in the last few months then grab one up the next time you hit a well stocked beer store.