Monday, June 10, 2013

Acid Malt Sour and Nectarine Tasting

It is easy to settle into a rut when it comes to brewing sour beers. These beers can take so much time, and are inherently so risky that many brewers (including me) latch onto the first technique that produces enjoyable beer. My standard technique is to pitch all of the microbes (including a healthy dose of brewer’s yeast) into primary, and rack to secondary a few weeks later for long term aging.

When I heard that Ithaca adds (added?) a large percentage of acid malt to Brute to sour it, I was suspicious. Given the logarithmic nature of pH, I found it hard to believe a beer as sour as Brute could be fermented with nothing but ale yeast and Brett (in the absence of lactic acid bacteria). So a couple years ago I decided to give a similar process a try. The wort on brew day didn’t taste particularly sour, but I was surprised by the end result.

I aged half the batch on white nectarines, a fruit that I’ve used before with great results, and one I’m sure will find its way to work into a few barrels of sour beer at Modern Times!

Acid Malt Sour, in a Ikea wine glass.Acid Malt Sour

Appearance – Crystal clear burnt golden colored body supports a small white head. Decent retention for a sour beer, especially considering some of my other recent efforts.

Smell – The aroma is fruity (apples and pears) and lactic, like a soured version of Duvel. There is some toastiness in the aroma, which I wouldn’t have expected from the grist (Pils, acid, and wheat malt), possibly from the Brett. The right notes are there, but the volume could be turned up. As it warms some floral tones appear and it starts to show its strength (although it doesn't taste the 8.2% ABV that the hydrometer suggests).

Taste – Snappy, tangy lactic acidity. The fruitiness from the nose remains, but here it is layered with clay. A hint of the spice from the saison strain primary remains as well. Still tastes very fresh, the Brett did its job nicely in that department.

Mouthfeel – Medium body, fuller than most sour beers (a trait it shares with Brute). Mildly prickly carbonation, about right.

Drinkability & Notes – A very solid, if subtle, golden sour. The acid malt did its job providing enough lactic acidity, and the Brett finished things out as expected. This method doesn’t save much (any?) time over a classic mixed fermentation, but it might be fun to try with 100% Brett!

Acid Malt Sour infused with Nectarines.W/ White Nectarines

Appearance – Nearly identical appearance, although not quite as clear. Not sure if the fruit caused the haze or if that is a result of the shorter time in the bottle.

Smell – Huge fresh nectarine aromatics. On first whiff you might be fooled into thinking you are opening a can of peaches in heavy syrup, but as it opens up the aroma gets fresher and more nuanced (pear, tropical etc.). I also get hints of the underlying Brett complexity, but this is really a showcase for the fruit.

Taste – The flavor is very juicy, with nectarines specifically (more clearly than the aroma) lasting into the finish. Very fresh and vibrant tasting. Similar level of acidity to the straight version, which is an indication that there weren’t a lot of lactic acid bacteria at work when all that simple sugar from the fruit was added.

Mouthfeel – Feels lighter than the plain version. The added water from the fruit seems to have thinned out the body more to where I usually expect my sours to be. Carbonation is similar to the fruit-less portion, but on this one I wouldn’t mind slightly more bubbly.

Drinkability & Notes – Terrific fruit character and a base beer that stays out of the way. I’m not quite as enthusiastic about it as the nectarine-aged wine barrel single, but it is pretty damn good. I think we can agree there are enough sours aged on cherries and raspberries; go to your local farmer’s market, try some samples of the “other” fruit, and buy a few pounds of your favorite to toss into a sour!


Anonymous said...

I'm thinking of using this high acid malt content idea to add a bit of character to a bier de table. My plan for a recipe is:

4 lbs pilsner
1 lb pale wheat
1 lb acid malt
1/2 lb C40
1 oz Simcoe @ 10 minutes
1 oz Cascade @ flameout
zest from an orange or two added at flameout

Might be a disaster, but maybe it'll be good and interesting

The Mad Fermentationist (Mike) said...

Sounds like an interesting plan! As I did, it is probably a good idea to wait until after conversion to add the acid malt so it doesn’t disrupt the enzymes in the mash. Without Brett you won’t have anything to finish off the fermentation if conversion is poor.

Let me know how it goes!

Dylan Bargteil said...

(I made the comment with the recipe, but OpenID isn't accepting my credentials to comment.)

I've been drinking the recipe I posted for a couple weeks now. I changed the pilsner to 2-row and bumped it up to 4.5 lbs, and took the acid malt down to 12 oz (11%). I also dry hopped with 2 oz of Simcoe for a week. I think it came out great, big citrus aroma, very crisp on the palate, and at just the right level of bitterness. It's a little thin, which becomes more noticeable with warming.

Next time I'm going to replace the 2-row with Vienna and bump the acid malt up to 1 lb 2 oz (17%).

Dylan Bargteil said...

Also, I did follow your advice about the mash -- it attenuated to 1.009 with S-04, which was about 72% AA, so it seems I encountered no trouble there.

The Mad Fermentationist (Mike) said...

Glad to hear it turned out well!

FaintYoungSun said...

Will try! Might I ask, what glasses those may be? Thanks for the amazing blog! ^_^

The Mad Fermentationist (Mike) said...

I get the most questions about those. They were from Ikea (Ivrig White Wine Glass), but last time I was in there they'd gone through a redesign - not quite as angular.