Friday, June 16, 2017

Starting Gun Ale - A Yeast Revival and Brewing Experiment

The five variants of Starting Gun Ale
While taking an inventory of my brewing supplies this week, I noticed that I had five packages of yeast that were older than I realized. One had no date on it at all. Another was past its "best by" date, and the last was over two years old (and I decided to throw it out).

Rather than let these yeasts go to waste, I decided I should probably grow them so they'd be usable when I am ready for them.

I could do that by mixing up a batch of "Fast Pitch" wort starter from cans and using my stir plate.  That would mean spending at least $10 on the cans of starter. I'd have nothing to show for it but the yeast, which would be OK but kind of a waste of time and materials.

A good yeast starter wort is typically said to have an Original Gravity (OG) of 1.036 to 1.040.  I decided to build a wort recipe with a gravity of 1.040 SG (10.0 Brix) to use as a yeast starter. Rather than make a disposable wort that served as a starter and was then tossed out, I decided to use it as an experiment for learning how different yeasts affect a beer's flavor. My goal is for this to turn out a drinkable (albeit weak) beer using different yeasts.  Then I'll have those yeasts available for upcoming brew sessions.

I decided to start with a mix of 2-row pale, Munich, Vienna, and Caramel malts so there would be some decent underlying malt complexity. It's loosely based on an Oktoberfest formula. That should be compatible with all the yeasts I'm using and is similar enough to the worts I'll eventually use the yeast on to ensure that the yeast can handle them. I decided to use Czech Saaz hops to bitter, flavor, and provide aroma, as they are a noble variety that's used across many beer styles.  I also wanted to try a hopping approach that I hear is becoming more popular, which is using late additions to accentuate the hop flavor without adding too much bitterness. I'm timing the hops additions so that the majority of the bitterness comes from late additions.

The Ingredients

5.25 pounds of 2-row Brewer's Malt
1.00 pounds of Munich Malt
6 ounces of Vienna Malt
6 ounces of Caramel 40L Malt
0.15 ounces of Czech Saaz @ 3.0% AA - 60 minutes
0.25 ounces of Czech Saaz @ 3.0% AA - 30 minutes
0.50 ounces of Czech Saaz @ 3.0% AA - 15 minutes
2 ounces of Czech Saaz @ 3.0% AA - 5 minutes
1/4 tsp. Yeast Nutrient
1 Whirlfloc tablet
1 vial White Labs Clarity Ferm spread across all batches.

Estimated OG: 1.040 (10 Brix)
Actual OG:  1.038 (9.5 Brix)
Bitterness: 11.4 IBUs
Color: 5.2 SRM
Estimated ABV: 4.1%
Total Grains: 7.00 pounds
Total Hops: 2.90 ounces
Estimated Pre-Boil Gravity: 1.036 SG (9 Brix)
Estimated Final Gravity: 1.009 SG
BH Efficiency: 80%
Batch Size: 5.1 gallons (estimated), actual approx 5.0 + kettle trub

The Yeasts

Using the Brewer's Friend Yeast Starter Calculator, I worked out roughly how much yeast remained alive in the containers, and settled on wort volumes that would hopefully grow that yeast to my desired amounts for future brewing.

The yeasts I'll be growing include:

  • Wyeast Denny's Favorite 50 (about 3 months old)
  • White Labs WLP028 Edinburgh Scottish Ale Yeast (past its best-by date, may be dead)
  • White Labs WLP510 Bastogne Ale Yeast (within its best-by date but I'll need a bunch for the beer I have in mind)
  • Omega OYL-028 Belgian Ale W Yeast (unknown age, no date visible in package, may be completely dead)
  • A jar of Wyeast 3787 that I grew back in March using Fast Pitch starter wort

My goal is to brew a 5.1 gallon batch (Why 5.1 and not 5.0? The Grainfather calculations always seem to end up with 5.1 gallons post-boil so I use that amount to ensure proper gravity. Your mileage may vary.) and then split the batch up into four parts:

  • 1.25 gallons for Denny's Favorite 50
  • 1.25 gallons for Bastogne
  • The rest split between Edinburgh, Omega OYL-028, and Wyeast 3787

This means that I'll effectively have six beers fermenting in my basement when I'm finished.  (I have an IPA and a Belgian Tripel in fermenters already.)  That's the most I've ever had going at once!

The Mash

I decided to do a Hochkurz Mash for this brew, so that the wort is very fermentable and the yeast has lots of sugar to grow on.  The mash schedule I'm using is;
  • 30 minutes at 145F for Alpha Amylase
  • 30 minutes at 160F for Beta Amylase
  • 10 minutes Mash Out at 167F
I'll be using 2.5 gallons of mash water treated with half a Campden Tablet to remove chlorine and chloramine and 4.75 gallons of sparge water treated with a Campden Tablet.

This should result in a 6.4 gallon pre-boil volume.

The Boil

I used a 60-minute boil schedule, with hops loaded toward the end of the boil to provide more flavor and less bitterness. The goal is a beer that is relatively balanced but not over-hopped given that it's going to be fairly low gravity.  So 11.4 IBUs might not sound like a lot to an IPA fan but in a beer with such low gravity that's a BU:GU ratio of 0.282.  It should work out to be fairly balanced unless the beer attenuates really well, in which case it'll tend toward the hoppy side.
  • 60 minutes: Add 0.15 ounces Saaz
  • 30 minutes Add 0.25 ounces Saaz
  • 15 minutes: Add 0.50 ounces Saaz, yeast nutrient, and whirlfloc
  • 7 minutes: Recirculate wort through chiller to sterilize it
  • 5 minutes: Add 2 ounces Saaz
  • 0 minutes: Turn off heat, begin cooling the chiller, and pump wort into the fermenter
I expect 5.1 gallons of wort, but will be splitting it across several vessels to allow for growing multiple varieties of yeast (as noted earlier).

The Fermentation

The plan is to let the yeast ferment without any attempt at temperature control. The low ambient temperature in my basement combined with the comparatively small volumes of wort should mean that the temperatures won't rise especially high during fermentation, but that does mean that I'm taking a risk that a given yeast won't overheat and generate off-flavors. Since this is a fairly low gravity wort, that seems unlikely to happen.

Left to right: Wyeast 3787 Trappist High Gravity (front), Wyeast Denny's Favorite 50 (back), White Labs Edinburgh Scottish Ale (front), White Labs Bastogne Ale (back), Omega Labs OYL-028 Belgian Ale W (front)
In the above photo, you see the five fermenters and their wort. The yeasts were all within or near their "best by" dates, except possibly the Omega yeast - which had no easily identifiable date on it. (Since I don't recall when I bought it, it might have no living cells left in it.  Any worts that don't show signs of fermentation within 48-72 hours will likely have a similar fresh dry (or liquid) yeast pitched in to ensure that I don't waste the wort.

Once they're all fermented and bottle conditioned, I'm planning to do a taste test here to see how one wort with five yeasts can end up with different flavors.

Update June 17, 2017:  All yeast strains but the Scottish ale strain show activity. The Wyeast 3787 Trappist High Gravity strain was beginning to clog its airlock, so I replaced it with a clean airlock. Within a few minutes I saw yeast accumulating in that one too, so I rigged up a blow off tube (shown below). I also put the Scottish ale yeast on a magnetic stir plate to try to revive it by introducing additional oxygen. If there is no indication of activity tomorrow, I'll consider pitching in another strain like Safale English Ale yeast.

Left is the Wyeast 3787 which needed a blow-off tube (plus I moved it to the sink in case there was any overflow). Right is the Omega Labs OYL-028 Belgian Ale W yeast which also has a thick krausen atop it.

Update June 18, 2017:  Today even the Scottish strain shows a small krausen in the fermenter. It will be interesting to see if, when that portion of wort is finished fermenting, we really have Scottish Ale yeast or something perhaps picked up out of the air.  The Wyeast 3787 is still bubbling actively and has turned the previously-clear water in the blow-off vessel a milky beige.  The Denny's Favorite 50 yeast shows signs of the yeast beginning to drop out of suspension, as does the Bastogne yeast.  The Omega yeast has about an inch and a quarter of krausen on top and seems to be working fine. All five yeasts at this point appear to be alive and well.  My plan is for all these yeasts to have at least a full week (preferably two) in the wort before I bottle the beers and harvest the yeast in the fermenters.

(Presumably) Edinburgh Ale Yeast, fermenting nicely now. If it's not Edinburgh, then it's an active wild yeast.
Wyeast 3787 (left) has blown a good bit of material into the blow-off vessel and changed the liquid from clear to milky. Omega Belgian Ale W on right still fermenting the wort.

Denny's Favorite 50 has almost lost its krausen and seems to be dropping out of suspension gradually
Bastogne appears to be finishing up and dropping out of suspension also
June 20, 2017:  The Bastogne, Denny's Favorite 50, and Edinburgh yeasts have mostly settled out of the wort. A wispy layer of foam remains atop the wort and there is no longer any visible airlock activity. The Trappist High Gravity yeast, Omega Belgian Ale W, and Edinburgh yeasts still show some signs of airlock activity. Compared with a couple of days ago, all the fermenter contents are clearer and show little or no motion.  This relative lack of activity is consistent with normal, healthy yeast activity.  While I was checking on the beer, I took the time to complete the washing of a prior batch of White Labs California Ale yeast from an IPA I made recently, and started washing the yeast I kept from an Australian Sparkling Ale.  That yeast was harvested back in April, so it will need to be revived as soon as one of these fermenters becomes available.  I anticipate being able to bottle some or all of these beers this coming weekend.

June 25, 2017:  Virtually all the beers have stopped actively (or at least visibly) fermenting. The fermenters contain very clear-looking beer with little floating on top of them, so I'm concluding that they are probably done fermenting.  I bottled all five variants today and harvested the yeast for future use.  Some of the beers had small amounts left over after bottling. I tasted those but have to say there wasn't much difference between them.  The one with Wyeast 3787 had a bit more of a Belgian flavor to it. The Denny's 50 had no discernible yeast flavors.  The Edinburgh Scottish version seemed maybe a little more malty.  But the differences are extremely subtle.  The experiment yielded 43 bottles at 12 ounces each, divided among the five yeast strains.  Yeast has been harvested and placed in cold storage.

Post-Mortem and Tasting Notes

When all of the yeasts finished fermentation and settled out of the beer, I bottled it. Each bottle was labeled with the recipe (for friends who are brewers) and the yeast strain used to ferment that variant of the beer.  I chilled a set of five bottles, then opened and poured them:


In the photo above, you see the five variants of Starting Gun Ale.  From left to right, the version fermented with Wyeast Denny's Favorite 50, White Labs Scottish Edinburgh, White Labs Bastogne, Wyeast 3787 Trappist High Gravity, and Omega Labs Belgian Ale W.

Here are my tasting notes on each variant:

  • Omega Labs OYL-028 Belgian Ale W Yeast:  The aroma is a mix of malt, fruit, and floral notes.  The flavor starts and finishes dry.  The finish is clean, less bitter than Wyeast Trappist High Gravity, but more than White Labs Bastogne.
    • Compared with the Omega yeast, D50 was more buttery and malty.  Omega had a more citrusy and fruity aroma, with more spice to the flavor.  D50 was more "basic" in its flavor.
    • Compared with the Omega yeast, the Scottish aroma was milder and malty.  The Omega aroma was more fruity.  The Scottish yeast yielded a more malty flavor.  The Omega yeast had a bit of clove and fruit to the flavor.
    • Compared with OYL-028, Bastogne had a more funky aroma.  Bastogne is more Saison like, while OYL-028 is cleaner.
    • The aroma of the Wyeast 3787 beer and the Omega yeast are very similar.  The Omega beer might have a bit more clove and spice aroma to it.  The Omega beer is more dry and malty, but 3787 seemed less flavorful overall.
  • Wyeast 3787 Trappist High Gravity Yeast:  The aroma is fruity and clearly Belgian.  The flavor has a hint of sweetness to it, and is malty with a hint of fruit and spice.  There is less overall flavor than the Omega yeast. The finish is more hoppy and bitter than the Omega yeast and the Bastogne yeast.
    • The aroma of the Wyeast 3787 beer and the Omega yeast are very similar.  The Omega beer might have a bit more clove and spice aroma to it.  The Omega beer is more dry and malty, but 3787 seemed less flavorful overall.
    • Compared with Wyeast 3787, the 3787 strain is more spicy and floral.  The Scottish yeast had a much thicker mouthfeel, while 3787 was probably the thinnest.
    • Compared with Wyeast 3787, D50 was cleaner, more neutral, and malty. The 3787 has a more spicy, fruity aroma.  The finish of 3787 seemed more bitter.
    • When compared with the Wyeast 3787, Bastogne had a more funky aroma, while the Wyeast had a more fruity aroma.  The 3787 flavor was cleaner, not as funky, and the beer seemed to have a thinner mouthfeel.
  • White Labs WLP510 Bastogne Yeast:  The aroma is more complex than Wyeast 3787 or the Omega yeast.  It has a funky element to it, like a Saison.  It has citrus and floral notes to it.  The flavor is more fruity and funky than the above two yeasts.
    • When compared with the Wyeast 3787, Bastogne had a more funky aroma, while the Wyeast had a more fruity aroma.  The 3787 flavor was cleaner, not as funky, and the beer seemed to have a thinner mouthfeel.
    • Compared with OYL-028, Bastogne had a more funky aroma.  Bastogne is more Saison like, while OYL-028 is cleaner.
    • Compared with the Bastogne yeast, Bastogne had a more complex aroma.  The Scottish aroma was more malty.  Bastogne had a more funky, floral, Saison-like aroma.
    • Compared with Bastogne, Denny's 50 had a cleaner aroma and flavor.  Bastogne seemed more funky and Saison like, where Denny's seemed more basic - but more sessionable.
  • White Labs WLP028 Scottish Edinburgh Yeast:  The aroma is more malty than anything else, with maybe a hint of butterscotch. The flavor is malty, dry, and has a clean finish.  It's more malty than Denny's Favorite 50.  It seemed to have a more substantial mouthfeel, and its head seemed to last the longest of the five.
    • Compared with the Bastogne yeast, Bastogne had a more complex aroma.  The Scottish aroma was more malty.  Bastogne had a more funky, floral, Saison-like aroma.
    • Compared with Wyeast 3787, the 3787 strain is more spicy and floral.  The Scottish yeast had a much thicker mouthfeel, while 3787 was probably the thinnest.
    • Compared with the Omega yeast, the Scottish aroma was milder and malty.  The Omega aroma was more fruity.  The Scottish yeast yielded a more malty flavor.  The Omega yeast had a bit of clove and fruit to the flavor.
    • Compared with the Edinburgh yeast, Denny's Favorite 50 seems to have less malt flavor in the middle of the sip.  Denny's seemed to make the hops more noticeable. The Denny's yeast finished more bitter, too.
  • Wyeast 1450 Denny's Favorite 50:  There is minimal aroma on this one, compared with the others.  What's there is mostly malty with a hint of caramel.  The flavor is dry, and comes across more hoppy than the others.  There's a hint of diacetyl to it as well, which may mean it needed more conditioning time.
    • Compared with the Edinburgh yeast, Denny's Favorite 50 seems to have less malt flavor in the middle of the sip.  Denny's seemed to make the hops more noticeable. The Denny's yeast finished more bitter, too.
    • Compared with Bastogne, it's a cleaner aroma and flavor.  Bastogne seemed more funky and Saison like, where Denny's seemed more basic - but more sessionable.
    • Compared with Wyeast 3787, D50 was cleaner, more neutral, and malty. The 3787 has a more spicy, fruity aroma.  The finish of 3787 seemed more bitter.
    • Compared with the Omega yeast, D50 was more buttery and malty.  Omega had a more citrusy and fruity aroma, with more spice to the flavor.  D50 was more "basic" in its flavor.
After compiling all these notes, my wife and I then decided to rank the beers from best to worst.  The ranking came out this way:
  • Wyeast 1450 Denny's Favorite 50: For this particular base beer, the Denny's Favorite 50 yeast seemed to make the beer more sessionable and easy to drink.
  • Omega Labs OYL-028 Belgian Ale W Yeast: While I think the Bastogne yeast made a more complex and interesting beer, both in terms of flavor and aroma, I can imagine myself drinking more of the beer made with the Omega yeast.
  • Wyeast 3787 Trappist High Gravity Yeast: This beer came out a bit thinner and less flavorful than the Omega yeast, but still pretty drinkable.
  • White Labs WLP510 Bastogne Yeast: This was probably the most interesting beer in terms of flavor and aroma, but I couldn't imagine myself drinking more than a bottle of it at a time.  I'll probably try this yeast when I decide to try brewing a Saison.
  • White Labs WLP028 Scottish Edinburgh Yeast: This yeast produced a fairly boring beer in this case.  It was drinkable, and there was nothing really "wrong" with it, but it just didn't impress me in any particular way. I would still use it when brewing a Scottish ale.  
It's also worth mentioning that the technique of obtaining most of the bittering through late-addition hops yielded an interesting result.  While there was plenty of hop flavor to offset the malt, the bitterness seemed "softer" and easier to drink.  


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