Computing ABV

A recent question on http://homebrew.stackexchange.com/ asked for a simple formula for calculating the percentage alcohol by volume (ABV) of a beer given the original gravity (OG) and final gravity (FG). Here was the complicated formula which was to be simplified:



OK, so it's not that complicated, but a linearization would be good. The original post suggested a range of 1.035-1.095 for OG and 1.002-1.028 for FG. I chose the midpoints of these intervals to get the point (1.065,1.015) and linearized the given formula at this point. Here's what I got:



It's simpler, but not easy to remember. If we round the coefficients, we get an easier to handle expression.



Analysis using Maple shows that this simplified linear approximation has an error of at most 0.78 from the original equation. This is not too hard to remember, since 147-130=17. Also, if both OG and FG are equal to one (the specific gravity of water), then the formula predicts 0% ABV.

DIY 1 Gallon Primary

I've been working on being able to brew one gallon recipes, and I decided to make my own primary fermenting tank for these small batches.

West Coast IPA

Qbrew

Since I've started designing my own recipes, I needed a nice tool to help me keep track of estimated OG, FG, ABV, IBUs, and various other abbreviations for important statistics.

One Gallon Batches

I've been a regular reader of BrewAdvice, a home brewing Q&A site. Home brewers of all levels of experience and expertise ask and answer questions about culturing yeast, choosing hops, krausening, and generally anything that piques their curiosity while brewing. I've asked a few questions about making mead, mixing yeast, and Sarsaparilla beer. A recent question about brewing small batches got me thinking that one gallon batch sizes might be a good way to develop a recipe. 

Hot town, saison in the city

When you're a homebrewer, everyone wants to hear about what you do. This is one of the great things about homebrewing as a hobby.

Sacking the Sack

A colleague of mine was cleaning out his house and came across two of these and gave them to me:

Fermentation Cogitation

(Editor's Note: This post originally appeared on http://sites.google.com/site/billsbrewing on June 21, 2010)

The two beers which I have fermenting right now are the Light and the Dark. Each of these was brewed with the same yeast strain, White Labs American Ale Yeast WPL060. They are being stored in the same location, and so have been kept at the same temperature. However,the Light has seemed much more aggressive in its fermentation. I had to switch out my standard three-piece air lock for my makeshift vinyl-tubing-submerged-in-a-bucket-of-water air lock.

Square Footage

(Editor's Note: This post originally appeared on http://sites.google.com/site/billsbrewing on June 19, 2010)

My home brewing has taken up very little space in our Swarthmore apartment. To see what I mean, just have a look at the current space which is dedicated to all things brewing:

The Light and The Dark

(Editor's note: This post originally appeared on http://sites.google.com/site/billsbrewing/ on June 17, 2010)

The move to LA is coming up soon, and so the number of available brewing days is few. So few, in fact, that today I brewed for the last time ever...

Bottling Days

(Editor's note: This post originally appeared on http://sites.google.com/site/billsbrewing/ on June 16, 2010)

Today is a bottling day. Tomorrow is as well. Here's what bottling entails, in case you were wondering.

Dark

Description
This recipe is mainly to use up leftover beer ingredients before the move to Los Angeles. It has a partner in crime: Light.
Recipe
Grain bill:

• 3/4 lb. Roasted Barley
• 3/4 lb. Chocolate
• 2/3 lb. Black

Extracts:

• 6.6 lbs. Dark Extract
• 0.5 lbs. Dark Candi Sugar

Hops:

• 1 oz. Cascade (60 min.)
• 1/2 oz. Willamette (15 min.)
• 1/2 oz. Willamette (dry hop)

Yeast:

• White Labs American Ale Yeast WLP060

Notes:

The dry hopping was skipped with this one.

Photos

Light

Description
This recipe is mainly to use up leftover beer ingredients before the move to Los Angeles. It has a partner in crime: Dark.
Recipe
Grain bill:

• 1/2 lb. Belgian Biscuit
• 3/4 lb. Extra Dark Crystal

Extracts:

• 1.5 lbs. Amber Malt Extract
• 3.3 lbs. Light Extract
• 3.3 lbs. Extra Light Extract

Hops:

• 1 oz. Cascade (60 min.)
• 1/2 oz. Willamette (15 min.)
• 1/2 oz. Willamette (dry hop)

Yeast:

• White Labs American Ale Yeast WLP060

Notes:

Photos

Winter Ale

Description

I found this recipe somewhere on the web and omitted ALL of the spice ingredients when I brewed it.

Recipe

Grain bill:

• 1/2 lb. Crystal
• 2 oz. Black Patent

Extracts:

• 6.6 lbs. Pale Malt Extract
• 1 lb. Honey

Hops:

• 2 oz. Cascade (40 min.)
• 1/2 oz. Saaz (5 min.)

Yeast:

• Wyeast 1056 American Ale Yeast

Additives:

• 1 oz. Ginger root
• 2-3 cinnamon sticks
• 1 oz. dried lemon peel

Notes:

The spices are added at the same time as the Saaz hops (5 minutes left in the boil). But I didn't add them. I don't know. It sounds kinda... terrible with those spices. I was mostly looking for a nice dark ale for the winter without the cliche. I will look elsewhere in the future.

Photos

Pumpkin Ale

Description
This one also came from George at Home Sweet Home Brew.
Recipe
Grain bill:

• 6 lbs. 10 oz. Canned Pumpkin
• 1 lb. Extra Special (Breiss)
• 1 lb. 2-Row Pilsen (Harrington)

Extracts:

• 6.6 lbs. Northwestern Gold

Hops:

• 1 oz. Tradition Hallertau (4.6%) (60 min.)
• 3 Tbs. Pie Spice (15 min.)

Yeast:

• Dry Ale Yeast (Safale S-04)

Notes:
The pumpkin gets steeped in its own cheese cloth at the same time as the rest of the grains.
When I made this one, I didn't have enough premixed pie spices, so I used equal parts cinnamon, ginger, and nutmeg. I do NOT recommend this. Nutmeg is stronger than the other spices, and it's probably best to use the ratio that are used in the premixed pie spice containers (whatever that may be).
Photos

English Pale Ale

Description
I wanted to make something hoppy, but not crazy hoppy. This is what George at Home Sweet Home Brew came up with.
Recipe
Grain bill:

• 1 lb. Cara??
• 1 lb. Cara??

Extracts:

• 1 lb. Light dry
• 1 lb. Demerara??
• 4 lbs. Light extract

Hops:

• 1 oz. First Gold (60 min.)
• 1.5 oz. WGU Golding (0 min.)
• 1/2 oz. WGU Golding (dry hop)

Yeast:

• dry yeast S-04 (English Ale Yeast)

Notes:
I intended initially to use some yeast I harvested from a previous brew, but it was dead, so I opted for the dry yeast I had as a back-up.

Photos

Blackberry Wheat

Description
This recipe and the ingredients came from George at Home Sweet Home Brew.

Recipe
Grain bill:

• 1 lb. Carapils

Extracts:

• 1 lb. Wheat Dry
• 4 lb. Wheat Syrup
• 1 lb. Raspberry Honey

Hops:

• 1 oz. Select 60 min.
• No aroma hops!

Yeast:

• Wyeast 1010

Additives:

• 1 oz. Blackberry Flavoring

Notes:
Since berries were out of season when I made this, I opted for natural berry flavoring instead of whole fruit.
The flavoring is added just before bottling. It's strong stuff, so I added it "to taste," which for me meant that I added it until I could notice the blackberry flavor in the beer.

Photos

Coffee Stout II

Description
This is the second effort at a coffee stout. The stout portion of this recipe follows the Dry Stout recipe in Charlie Papazian's The Complete Joy of Home Brewing. As with the Coffee Stout, a batch of cold brewed coffee is brewed and sterilized and added before bottling. I ordered my beer ingredients from Northern Brewer and got the coffee from The Head Nut in Swarthmore, PA.

Recipe
Grain bill:

• 3/4 lb. Crystal
• 1/3 lb. Black Roasted
• 1/3 lb. Roasted Barley

Extracts:

• 6.3 lbs. Dark Malt Syrup

Hops:

• 2 oz. Willamette (4.7%) (60 min.)

Yeast:

• Wyeast 1084 Irish Ale

Additives:

• 1 lb. Coffee

Notes:
Cold brew the coffee, sterilize, and add to beer before bottling. Original brew date 5/28/2010.

Photos

American Dubbel

Description
This recipe largely follows the Belgian Dubbel recipe in Charlie Papazian's The Complete Joy of Home Brewing. However, I decided to do some dry hopping with this one for a bit more hoppy aroma to balance the maltiness. I ordered my supplies from Northern Brewer.

Recipe
Grain bill:

• 1/2 lb. Crystal
• 1/4 lb. Chocolate
• 1/2 lb. Toasted

Extracts:

• 7.5 lbs. Amber Malt Syrup
• 1/2 lb. Candi Sugar

Hops:

• 2 oz. Goldings (60 min.)
• 1/2 oz. Mt. Hood (15 min.)
• 1/2 oz. Mt. Hood (dry hop)

 Yeast:

• White Labs Belgian Ale Yeast

Notes:
This one had a vigorous initial fermentation. I expected this and didn't use a standard three piece air lock. Instead, I attached one end of a hose to the carboy and the other end was submerged in a bucket of water. The bucket neatly collected the foam which would have clogged up the standard airlock and possibly could have even ejected the airlock, making a huge mess everywhere. Instead, the mess was nicely collected in the bucket.

Photos:

Coffee Stout