Wednesday, 11 January 2017

The Power of Staged Fermentation - Sour Grapes

Progression of the beer from: Day of grape addition (left) to 4 months later in the glass (right)
I am a bit of an experimentalist at heart, and one area in which I do a lot of "experimental" brews is using the staged addition of pure cultures of wild or commercial yeasts & bugs, pitched at varying times, to produce unique sour beers that cannot be produced through conventional brewing techniques. I've made beers with similar complexity to classical sour beers using staged-addition of bugs, but that's not what this post is about. Rather, this post is about using these methods to make good beer from difficult ingredients. In this case, wild grapes.

Wild grapes are pretty common place across North America, and they come in two "flavours" - European wine grapes that have escaped the vineyard and native species of grapes. Wild European grapes are pretty similar to the grapes you buy in the grocery store, and can be used as would any other wine grape in sour beer brewing. Truly wild grapes are another beast. In fact, my first attempt to brew with these turned a rather lacklustre 2-year old golden sour into an unpalatable mess. Thankfully I only added grapes to one gallon of that beer, and rescued the rest with a more classical cherry addition! There have been attempts since, and none (until now) were worth writing about.

There are nearly 70 species of wild grapes native to North America, so I'm not sure how true the following statements will be for brewers in other regions of N. America (or elsewhere), but for people in Ontario and the north-eastern US, this should be relatively accurate. The three species of wild grape native to my area (Vitis riparia, V. aestivalis and V. labrusca) are quite different from their European cousins. These grapes are much more intense than their European cousins; while the juice of European varieties are generally used to make wine undiluted, our local wild grapes need to have their juice diluted between 1:2 and 1:5 to produce a wine with a tolerable taste. The grapes themselves are quite small (0.5 cm diameter or smaller), have a very thick and tannic skin, have a much higher malic acid content, and have a much larger seed portion (relative to the amount of fruit) compared to their European cousins. And it is those characteristics that make them hard to incorporate into sour beer - essentially, enough grapes to give a nice grape flavour also imparts a lot of tannins, malic acid and grape-seed character.

Tannins are astringent and drying, and while nice in small amounts, they can quickly become overwhelming and unpleasant. Indeed, tannins are often made by plants for the purpose of deterring animals from eating the plant - the term "tannin" comes from their ability to tan leather, so you can imagine how excess amounts make your mouth feel. Malic acid is also quite harsh - almost as harsh as acetic acid - and like tannins can be pleasant in small amounts but becomes harsh and overwhelming quite easily. The seeds of grapes are also problematic - they contain some earthy and woody flavours that are pleasant, but the high seed content of wild grapes means these characters can be somewhat strong, and in my experience, clash with brett phenolics.

My attempts at using these grapes in conventional sours failed because of these characteristics - the malic acid would make an already acidic beer far too acidic and harsh, the seed character would amp up the funk, which in turn clashed with the high levels of tannins. Even pressing the grapes for juice doesn't solve these issues (aside from the grape seed flavour) to any meaningful extent. But where traditional sour brewing methods failed, "experimental" methods succeeded.

More Below the Fold

Thursday, 5 January 2017

Fact of Fiction - Can Pathogens Survive in Beer? The RDWHAHB Edition

Its time for the third instalment of my pseudo-series Can Pathogens Survive in Beer (Part 1 - of course they can, Part 2 - Moulds). To summarise parts I and II, yes there are a number of pathogens that survive in beer, and yes, moulds can release poisonous mycotoxins into beer, but generally speaking proper sanitation and controlling your brewing environment can eliminate these risks.

Today's edition is a little different; my previous posts get "cited" a lot by people who seem to have been scared by my posts away from testing new organisms as potential brewing bugs. As one example, a few months ago at Milk the Funk a discussion on the potential use of Lachancea fermentati (a lactic-acid producing yeast) to make a "single organism" sour-beer. The interest readily split into two groups after a case report was found of a patient in Texas who suffered fungemia (blood infection) with Lachancea fermentati. This led many people who at first were anxious to try brewing with this yeast to become fearful about even letting it near their brewery. Yet I, and a few others, made beers with this yeast...and we're all still here and no one got sick. So what is going on? Why would I (a microbiologist by trade) risk making a beer with a known pathogen?

The answer, as always, is below the fold...

Monday, 2 January 2017

Beer on the Brain - Your Lyin' Hydometer

I'm excited to announce the next video in my Beer on the Brain series...Your Lyin' Hydrometer. In this video I quickly discuss how hydrometer readings can lead you astray when brewing high gravity beers.


Sunday, 1 January 2017

2016 In Review

Last night, somewhere around midnight, 2016 came to an end...meaning its time for my annual look back at the year that was.

The Good: Both my blog and youtube channel continue to grow in popularity; my blog reaching 394k views, and my youtube channel 103k views. Most of the beers this year came out either good or excellent, including what may have been my best Berliner Weisse to-date. My brewing output is up slightly over last year - 16 beers/ciders, plus a few batches of wine. I added a bunch of fun yeasts to the yeast bank, and found two new loves in the form of Kveik yeast and fast-lagering with W34/70.

Of course, this year was also my 20th brewversary, and the celebration of that went well...and is still continuing.

The Bad: Brewing output is still down compared to historical norms, and I ran dry a few times this year. My posting of both blog posts and youtube videos has also suffered this year, despite starting a new series of short videos intended to overcome last years rather meagre offerings.

The Ugly: Turns out I was growing my hops all wrong...I hope to fix that in 2017.

Some Quick Stats

My Favourite Blogs of 2016

(in no particular order)
I cannot claim to have any big things planned for this year - more posts and videos, and ore brewdays, I hope. I also hope to electrify my brew setup...but those plans have been in the works for 3 years and have never advanced past the planning phase, so I'm not going to hold my breath on that one.