Tag Archives: fermentation science

Improving Beer by Math! Part 1

Back when I first started brewing beer, I used to just throw cans of extract together and hoping for the best when I had my Mr. Beer kit.  Although I had some mediocre results for the most part, I did have several beers that were truly superb from that method.  But one thing I did notice from that methodology, I didn’t have consistency.  Even if I tried to make the same recipe over again, there was too many variables to be able to produce the same beer over and over again.  For instance, the Alpha Acid percentage in hops, how viable your yeast is, protein content in the grains, hell..even the extracts can be variable (in regards to the long chain dextrins that yeast can’t metabolize).  With all these variables, I had to do something about it…but what?

As I made the jump from extract (pre-made brewing kits) to all-grain brewing (brewing from scratch), I found two books that made their way in my library as my Beer Bibles.  Gregory Noonan’s New Brewing Lager and John Palmer’s How to Brew really helped me understand the basics of the brewing beer.  Within those books I found that math is my answer to help my consistency problems, ranging from basic geometry formulas, complex logarithmic formulas, and even algebraic equations.  They seemed very intimidating at first, but then I realized that the formulas are merely just plug and chug equations.

Reason why I bring up the topic of Beer Math is because I was busy yesterday doing calculations for the grain bill and other parts of Copperhead Light Ale.  Copperhead Light Ale was originally an accident (just as the original Copperhead Ale), and I decided to give the “accident” a recipe overhaul because of the potential it has of being a great beer in our arsenal of beers we routinely brew.  The accident that created Copperhead Light originally started by forgetting to add a portion of the grain bill before brewing.  I didn’t notice the missing grains until I started sparging (separating the wort from the grains) and I saw that the wort (sugary goodness) was much lighter than it should have been.  From there Copperhead Light Ale was born (or should I say the pilot batch)!

This time around I decided to reduce the overall grain bill from the original Copperhead Ale by 20% (to make up the portion of the grain bill that I missed from the first time Copperhead Light was born from), by doing so that decreased my total weight I would use in grains in the original Copperhead Ale recipe.  Then I removed an additional 30%  from each grain addition to the recipe and replaced that with rice.  To make it more easier to follow here’s an example of the math I conducted:

Copperhead Ale Grain Bill Total 10lb’s; need to reduce grain bill by 20%:

10 × .20 = 2 lb’s

10 − 2 = 8 lb’s new grain bill weight for Copperhead Light

Copperhead Ale Light Grain Bill; reduced for Rice addition by 30%:

Pale Malt – 4 lb  –> 4 × .30 = 1.2 lb reduction

Vienna – 3.5 lb  –> 3.5 × .30 = 1.05 lb reduction

Crystal – .5 lb    –> .5 × .30 = 0.15 lb reduction

Add up your reduced grain bill:

Pale Malt – 2.8 lb

Vienna – 2.45 lb

Crystal – 0.35 lb

Total – 5.6 lb

Then add up your total lb reduction to get your new rice addition:

1.2 + 1.05 + 0.15 = 2.4 lb’s of rice

Check your math by adding your adding your grain bill and rice together to see if you got a total of 8 lbs that was originally desired:

5.6 + 2.4 = 8 lb’s  <– Success!!

Okay, okay, that was really easy but you get the point.  That was the basics of using math to help formulate a new grain bill.  Actually, there’s a lot more to it than that, I already had a pre-determined starting gravity/diastatic power of the grain from the grain bill and also determined how much the rice would offset the maltiness in this brew (please note that this is an example and not the real recipe, I just simplified it for everyone to understand).  Now that I got my grain bill I can now get started on brewing my beer!

Now to determine the strike temperature (initial infusion of hot water mixed with the grains), I need to know my grain bill weight, grain temperature, and volume of water, and desired temperature.  The following equation helps us determine the strike temperature for the mash:

Where:

Ts = strike water temperature in °F

Tt = target mash temperature in °F

Tg = dry grain temperature in °F

R = Water to grain ratio (in quarts to pound / ideally 1.00 – 1.125 qts per 1lb)

Formula: Ts = (0.2/R) ×(Tt – Tg) + Tt

For example: I have 8 lb grain bill and I want to mash in at 148F with only 2.25 gal of Hot Liquor (HL / HL is brewing term for hot water).  Crush your grains and take a temp reading, for example..say its 72F.  Now figure out your Water to Grain ratio by taking your total water volume and multiplying it by 4 (this converts to quarts) then, divide your answer by your grain bill.

R = 2.25 gal × 4 = 9 qts

R = 9 qts ÷ 8 lbs

R = 1.125

Now that I have my water to grain ratio, I can now continue on with the strike temperature formula!

Ts = (0.2/1.125) × (148 – 72) + 148

Ts = (0.1777) × (76) + 148

Ts = 13.51 + 148

Ts = 161.51ºF

Now I will need to heat my HL to 161.5F to bring my mash to 148F as planned!

Now that we got the strike temperature out of the way, I can start my mash!  After a pre-determined time at that rest temperature, I want to raise my mash to a new rest temperature of 158F.  Since I’m a huge fan of decoction mashing (decoction mashing is where you boil the thick portion of the mash in a separate kettle), I want to decoct my mash to get to the next temperature rest.  A way to do this is by either following the traditional methods of pulling a third of the thickest mash and transferring it into a different pot then boil it as long as needed and then later return the decocted portion until you reach your desired temperature rest and wait to add the remaining decocted mash until it has cooled to the desired temperature.  Or you can use the following equation without having to wait on your remaining grist to cool:

Where:

Dv = volume needed to pull from mash in gal to decoct

Tmt = target temperature of mash

Imt = initial temperature of mash (or current mash temp)

Gw = weight of grain

Wim = volume of water in the mash before infusion (or current water in mash volume)

Iv = volume of water to add to mash to achieve target mash temperature

Iwt = infusion boiling temperature (default 212F/100C) you can modify this to your sea level boiling temps

Formula: Dv = (Tmt – Imt) × (Gw × (0.3125 + (Wim ÷Gw))) ÷ (Iwt – Imt)

This can look very intimidating but be sure to remember your order of operations!  My current mash temperature is 148F, my grain weight is 8 lb’s, my current water volume in the mash is 2.25 gals, and my desired temperature is 158F.  So for example:

Dv = (158 – 148) × (8 ×(0.3125 + (2.25 ÷ 8))) ÷ (212 – 148)

Dv = 10 × (8 ×(0.3125 + 0.28125)) ÷ 64

Dv = 10 × (8 ×0.59375) ÷ 64

Dv = 10 × 4.75 ÷ 64

Dv = 47.5 ÷ 64

Dv = 0.74 gal

To raise my mash temp from 148F to 158F, I will need to pull 0.74 gal of grist to reach my desired temperature.  How long to boil the decoct is up to personal preference or if you’re trying to achieve melanoiden production.  So we then rest our mash at 158F at a pre-determined time and we need to mash out our grains.  How do we do it?  By decoction of course; so we use decoction to mash out our grains.  We then need to figure out how much sparge water we will need to get our pre-boil volume in the kettle.  To do that we use the following formula:

Where:

WGr = water to grain ratio

GAr = 0.13 grain absorption ratio

SWv = WGr × grain weight

GAv = GAr × grain weight

Sv = sparge volume

Bv = boil volume

Formula: Sv = (Bv ÷ 2) – (SWv – GAv)

For example:

Sv = (7 ÷ 2) – ((1.125 ×8) – (0.13 × 8))

Sv = 3.5 – (9 – 1.04)

Sv = 3.5 – 7.96

Sv = 4.46 gals of sparge water

For me to reach my target of pre-boil volume of 7 gallons I will need to prepare 4.46 gallons of HL to sparge my mash with.  So now I can heat my sparge liquor to 170F to sparge my mash!  This is just the tip of the iceburg when it comes to beer math.  I figured I could give everyone Beer Math 101 for the time being before I present a Beer Math 112 course!  At the moment, Copperhead Light Ale is almost finished sparging and it’s time to get a pre-boil starting gravity so I can do my 60 minute hop addition calculations!  😉  Till next time, cheers!

– James (Head Brewmaster)

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Wood & Lagers

Well back in the late 1800s, the Bohemian Pilsner (e.g. Urquell Pilsner) stirred a craze amongst brewmasters all over in order to create the palest and most thirst quenching lager known to man.  Among these light lagers that were created following the birth of the Pilsner was the Dortmunder Export (e.g. DAB Export), Munich Helles (e.g. Paulaner Premium Lager), Standard American Lager (e.g. Budwieser), Light American Lager (e.g. Coors Light), Premium American Lager (e.g. Coors Extra Gold), Classic American Pilsner (e.g. Our very own CAP), and German Pilsner (e.g. Warsteiner).  All of these light lagers do a really great job at quenching one’s thirst.

Brewing such beers are very challenging even to the most experience homebrewer and brewmaster.  Since these beers are so light in flavor and color and kind of flaw (from the yeast, hops, malt, etc..) becomes very evident in the final product.  Major brewery’s such as Anheuser-Busch or Coors have highly skilled brewmasters who are able to produce the same product batch after batch, year after year.  I find that absolutely amazing that no matter what ingredient variables they come across, in the end no matter what time of the day or year you pick up a Budweiser.  It will taste exactly like the Budweiser you had before.

As challenging as these beers are to brew, many homebrewers and brewmasters take the challenge in brewing pale lagers.  I plan on crafting the Standard American Lager which normally consists of 60% malt and 40% corn or rice, hangs around 8-15 IBU’s (bitterness), usually a pale 2-4 SRM (pale to golden straw colored), and weighs in at 4.2 – 5.1% ABV.  I decided to use Pilsner Malt and Rice at a 60/40 ratio and mashed (steeping grains in water to convert to sugar) at a very low temperature for 120 minutes.  This ensured I had full conversion of the starches from the rice and Pilsner malt itself. One type of hop called Cascade is being used for bitterness and flavor, just a minute amount is being added for aroma as it’s frowned upon to have hoppy aroma from this beer.  I’m still torn between using two different types of Lager yeast for this beer, upon completion I’ll be sure to update the yeast that was used in this brew.

As always, I’m a huge believer of First Wort Hopping (FWH), this is a process of adding hops to the kettle as I’m sparging (draining the wort from the grains) the wort (sugary goodness that yeast likes) before boiling.  I also plan on doing something very interesting to this beer, normally Budweiser is aged at cold temperatures on Beech Wood which makes it very unique from that process.  My plan is to age this American Lager on Apple Wood instead, to separate this beer apart from other American Lagers.  There’s not much data on aging beers on many woods other than French and American Oak and Beech, which makes it hard to determine how it will affect the lager.  For now the applewood chips are soaking in Ciroc vodka (we only use the best for our beers..lol) to sanitize the chips prior to adding to the lager in the secondary to age.  While waiting for this lager to finish up in the primary, come on down to the brewhouse and enjoy our beers we have on tap! 

-James (Head Brewmaster)


Crossing Into The Dark Side

36 hours on stir plate, WLP 001 first gen is at high krausen!

Let’s face it, there comes a time in every homebrewer’s or brewmaster’s life when they become curious about the wild side of fermentation.  Sure Saccharomyces cerevisiae & Saccharomyces pastorianus  (brewer’s yeast) is a great companion and all, but at times the wild critter’s are needed to achieve a certain beer style.  Of course there are several issues with crossing into the wild side of fermentation.  For instance, there’s not very much scientific/experience data out there with all of the wild critters that can help guide the average-Jo unless they have a Graduates in Fermentation Science or Microbiology.  These wild critters can be very unpredictable, general knowledge states that for beer to taste better to ferment on the cool side of the spectrum.  This prevents our S. Cerevisiae and S. Pastorianus comrades to put out nasty off flavors.  There are numerous of wild critters out there that are desired for certain beer styles, some of these styles include Berliner Weisse, Lambics, Flander’s Red Ale , Flander’s Oud Bruin, Fruit Lambic, Gueuze, Kriek, and several others.

5 lb’s, 60/40 Pils/Wheat ratio in the mash!

So what are these wild critters that I speak of?  Well, I won’t go into specific strains for there are far too many to list but I will give a general idea of what they are.  These include Brettanomyces, Pediococcus, Lactobacillus, Enterobacteriaceae, and Acetobactor.  I won’t go into the nitty gritty of the characteristics on the wild critter’s except for one as this is the critter that we’re focusing out attention on today in the brewhouse.  We’re seeking to brew a Berliner Weisse and this beer is very unique as it focuses on a symbiotic relationship between S. Cerevisiae and Lactobacillus delbrueckii or other strains of Lactobacillus.  But where does one get a hold of this known beer spoiling organism?  Well, there’s numerous of places in your house where you can obtain this critter.  Do you have cabbage or cucumbers in your fridge?  Well, chances are that you have Lactobacillus.  Got some Pilsner/2-row/6-row malt laying around?  Odds are you got Lactobacillus there too.  Got some yogurt with live culturs in it?  You definitely got your Lactobacillus in there (I’ve never tried this before, although it’s frowned upon through this route…).  In short, you have Lactobacillus in your house or brewery already.  Generally most homebrewer’s and brewmasters do everything in their power to avoid this critter.  Or if you’re lazy you can just buy a pure Lactobacillus culture from White Labs or Wyeast.Lactobacillus is actually a very temperamental organism, it doesn’t like oxygen, cold temperatures, and hops (for the most part).  There are some hop resilient strains out there, but White Labs and Wyeast strains do not like highly hopped beers.  We’re taking out chances by obtaining our Lacto bug from Brewferm Pilsner malt.  This particular batch is very dusty so we’re very curious on how this will turn out.  Our yeast strain of choice to ferment this out is WLP 001 Cali Ale yeast from White Labs.  It’s on a stir plate at high-krausen as we’re brewing today.  We’re also trying out a lot of different brewing techniques today as the brew day progresses.  For example, we’re mash hopping this beer with low alpha-acid hops (Hersbrucker), we’re single decocting this brew and proceeding with a no boil as well.  This is our smallest grain bill we’ve ever brewed with as well!  For this 5 gallon batch we’re only using 5 lb’s or grain with a 60/40 ratio of Pilsner/Wheat malt for this Berliner Weisse.

Below is the BJCP’s specs on this amazing beer:

17A. Berliner Weisse

Aroma: A sharply sour, somewhat acidic character is dominant. Can have up to a moderately fruity character. The fruitiness may increase with age and a flowery character may develop. A mild Brettanomyces aroma may be present. No hop aroma, diacetyl, or DMS.

Appearance: Very pale straw in color. Clarity ranges from clear to somewhat hazy. Large, dense, white head with poor retention due to high acidity and low protein and hop content. Always effervescent.

Flavor: Clean lactic sourness dominates and can be quite strong, although not so acidic as a lambic. Some complementary bready or grainy wheat flavor is generally noticeable. Hop bitterness is very low. A mild Brettanomyces character may be detected, as may a restrained fruitiness (both are optional). No hop flavor. No diacetyl or DMS.

Mouthfeel: Light body. Very dry finish. Very high carbonation. No sensation of alcohol.

Overall Impression: A very pale, sour, refreshing, low-alcohol wheat ale.

Comments: In Germany, it is classified as a Schankbier denoting a small beer of starting gravity in the range 7-8°P. Often served with the addition of a shot of sugar syrups (‘mit schuss’) flavored with raspberry (‘himbeer’) or woodruff (‘waldmeister’) or even mixed with Pils to counter the substantial sourness. Has been described by some as the most purely refreshing beer in the world.

History: A regional specialty of Berlin; referred to by Napoleon’s troops in 1809 as “the Champagne of the North” due to its lively and elegant character. Only two traditional breweries still produce the product.

Ingredients: Wheat malt content is typically 50% of the grist (as with all German wheat beers) with the remainder being Pilsner malt. A symbiotic fermentation with top-fermenting yeast and Lactobacillus delbruckii provides the sharp sourness, which may be enhanced by blending of beers of different ages during fermentation and by extended cool aging. Hop bitterness is extremely low. A single decoction mash with mash hopping is traditional.

Vital Statistics: OG: 1.028 – 1.032
IBUs: 3 – 8 FG: 1.003 – 1.006
SRM: 2 – 3 ABV: 2.8 – 3.8%

Commercial Examples: Schultheiss Berliner Weisse, Berliner Kindl Weisse, Nodding Head Berliner Weisse, Weihenstephan 1809 (unusual in its 5% ABV), Bahnhof Berliner Style Weisse, Southampton Berliner Weisse, Bethlehem Berliner Weisse, Three Floyds Deesko

Kettle full of grain dust and hand full of grains while sparging, wort temp 124F.

Our plans for this brew:

60/40 ratio for Pilsner and Wheat malt mashed at a low temperature to ensure an extremely fermentable beer.  Since we stove top mash in our kettle, we crushed the grain over the kettle to spread malt dust all over it (you’ll see why we did this in a minute).  We mashed in with 1 1/2 gallons of hot liquor (water) to the 5 lb’s of grain the mash tun was only a quarter of the way full (first time ever!).  After 20 minutes from mashing in we added 1 oz of Hersbrucker hops and according to our calculations that will bring us to 3 IBU’s of bitterness..craziness!  Our total time for mashing our grains was 90 minutes to ensure full conversion of the starches into precious sugars.  We then transferred the mash into our lautering tun and began fly sparging into the unwashed kettle.  It still has dust from the middle on up from when we crushed the grains and had some left over grains from the transfer.  This will give the Lactobacillus a head start on the brew because by the time the wort hits the kettle it’s at a temperature of 120F.  Which is the prime temperature for Lactobacillus to to it’s job of inoculating the wort, now it all makes sense! (as a side note, we sanitized anything that came into contact with this brew to prevent other nasty’s in getting into this brew) We’re also not boiling this brew to prevent DMS (a corn-like off flavor) since this is supposed to be a clean-crisp-refreshing beer.  To ensure Lacto does get inoculated in this brew we’re also tossing in a handful of grains as we sparge into the kettle.  Our starting OG for this brew is 1.028 @ 5.5 gallons, SRM (color) 2, and the IBU’s (bitterness) is around 3 (calculated), and 84% brewhouse efficiency!

B-Dub’s in the primary!

We plan on a 2 month fermentation regiment and bottling this brew, this beer is rarely found on tap and we plan to continue with the tradition of this very elusive brew.  This beer will be served with raspberry syrup when it’s ready and we look forward to raising a pint with you!

Cheers!- James (Head Brewmaster)


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