Twenty13 – EisGersteWein (Ice Barley Wine) – Part 1

          Last year I finally brewed a beer that broke the 1.100 mark. When it finished fermenting, it was my highest alcohol beer yet clocking in at 11.24% ABV. Then I heard all the buzz about Armageddon from BrewMeister (joke of a name!!) which clocks in at a whopping 65% abv. Damn buzz killers!  Envy set in quickly. For those who don’t already know, Armageddon is “freeze distilled” which removes water from the beer in the form of ice and leaves the residual malt sugars, hops and alcohol concentrated. It got me thinking about the time I was cold conditioning a bitter and accidentally froze it. The one gallon I got from the carboy was around 22% abv. !!

          I thought it would be great to do it right this time aiming to break the 20% abv mark. Most commercial breweries try to extrace 5 to 10% of the water as Ice, but BrewMeister must be extracting about 75%+ to achieve their 65% abv in Armageddon , so I decided to aim pretty high and try to match them with 68% of the water being extracted. It's not as hard as what they do to achieve a 130 proof beer, but it would be a good achievement if I could do it. I started with my Fullers London Pride clone recipe, then I increased all the malts by 60% and cut the hops by one third so the concentrated beer wouldn't be too bitter. Once the beer is frozen and concentrated, I hope the hop profile will measure around 75 IBU so the beer would still be balanced and drinkable.

          On brew day it was only 46 degrees outside. That’s pretty chilly for Orange County, CA.  I mashed at 151, but the day was so cold it dropped to 144 in no time even though the mash tun had a sleeping bag wrapped around it for insulation. Once I got it back up to 151 the conversion completed right away. In the boil I used First Wort Hopping to try and lock in a good amount of hop flavor too. I ended up with 9 gallons with an O.G of 1.065, but the effective OG is around 1.210 because of my plan to freeze the finished beer.

The English Ale (WLP002) yeast did an average job of fermenting the beer down to around 1.016 even though I wanted it to end up at 1.010. WLP002 is a VERY floccuative strain, and the cold-snap we had put it to sleep before I could really push the yeast.

(The twins)

          It looks like I’ll get about 2.75 gallons of beer at 20% abv, 75 IBU with an effective FG of 1.052. This should be a very rich winter warmer if I’ve ever heard of one! Most strong Barley Wines have a little less than half the alcohol and half the FG, but my IBU’s are right in line with the most American Barley Wines.

          Last night I used my Marks Keg Washer for the first time to clean up two kegs. After siphoning the beer into both, I ended up leaving 2 to 3 quarts of headspace. I’ll need this because the water in the beer will expand as it freezes. I hope to get the same chunky ice crystals I had in my accidentally frozen bitter. 

          My chest freezer was set to 20 degrees the day before the kegs were put inside. The kegs were put in the corner to maximize the cooling effect.

          After one day the beer was already a slushy at 23 degrees. According to laws of chemistry I will need to drop the beer to 18 degrees F in order to concentrate the beer to 20% abv. I turned the freezer down 10 degrees and gave each keg a swirl to get more ice to float up and liquid to separate downward.

(Beer Slushy anyone?!?!)

Geek Alert!

In order to figure out how much alcohol you want left in a liquid state you need to calculate how low of a temp the beer needs to reach.

Formula to calculate temp C needed for target ABV is:

=(((Target ABV/1.25)*1000)/46.06844)/(1-(Target ABV/1.25))*1.86*( -1)

Convert the Target ABV% to its decimal equivalent for the above formula.

Some results from this formula tell us how far down we need to drive the temp on our finished beer so the extracted EisBier has the alcohol level we desire.

10% abv   - 3.5 C  or    25.68 F
20% abv    -7.7 C  or    18.16 F
30% abv  -12.7 C  or      9.15 F
40% abv  -18.9 C  or    -2.20 F
50% abv  -26.9 C  or  -48.45 F

Please note that a tiny bit of the alcohol and the hops will be caught up in the frozen water, but the vast majority will make it into the beer you extract.

In the next installment we’ll discuss Spunding Valves….they’re not as kinky as they sound, but they can be very useful when you need to relieve some pressure or used to naturally carbonate when your beer is sitting in secondary in a corny keg.

The new home of The Homebrew Dude

Many years ago I answered brewing questions from around the world on a friend's web site called WhatAlesYou.com  I thought it would be fun to start a blog where I could help out fellow brewers again and share the discoveries I've made during my own brewing sessions, so Brewnundrum was started.

In this blog I hope to explain in the scientific cause and empirically observable effect of what we do as brewers. George Fix did that really well in his second book An Analysis of Brewing Techniques. Every brewer needs "skills" in their arsenal so they can brew world class beers. I hope this blog helps explain brewing situations and how to handle them if you don't have an arsenal of scientific instruments at your disposal. I encourage everyone to develop their brewing "skills", know how to use them, recognize when they're needed and understand how they all work together so you can brew world class beers. Simple, right?

A little about me: I'm just a homebrewer, but I'm in my 20th year of brewing now. While not an active judge, I attained National Judge ranking with the BJCP. I've attended the Advanced Homebrewers course at the American Brewers Guild, the Introduction to Brewing course at the UCSD Extension, and the Introduction to Brewing Science at the UCR Extension. I've run beginning and intermediate homebrewers' classes, made many presentations at homebrew club meetings, done several all-grain brewing demonstrations for local homebrew supply stores. I am also a past president of the Crown of the Valley Brewing Society. 

Several of my beers have won, or placed 2nd at the AHA National Homebrew Contest (regional round) and at the America's Finest City brewing Contest. While I brew all styles of beer and hard cider too, my current focus is on brewing beautiful, varied Saisons, Trappist style ales and the Soured 7 barrel project which Scott Bennett has mentioned in his blog previously. 

Needless to say, my homebrewing friends think I'm a bit of a brewing geek. My style of brewing is very grounded in the creative craft side of home brewing, but it is also well grounded in scientific and mathematical brewing principals....I brew by the numbers as I say because they tell me a story.

Original Aeration Presentation

Aeration

From Wikipedia: Aeration (also called aerification) is the process by which air is circulated through, mixed with or dissolved in a liquid or substance.

Aeration of liquids (usually water) is achieved by:

• Passing the liquid through air by means of fountains, cascades, paddle-wheels or cones.
• Passing air through the liquid by means of the Venturi tube, aeration turbines or compressed air which can be combined with diffuser(s) air stone(s), as well as fine bubble diffusers, coarse bubble diffusers or linear aeration tubing. Ceramics are suitable for this purpose, often involving dispersion of fine air or gas bubbles through the porous ceramic into a liquid. The smaller the bubbles, the more gas is exposed to the liquid increasing the gas transfer efficiency. Diffusers or spargers can also be designed into the system to cause turbulence or mixing if desired.

For Homebrewers: Adding dissolved oxygen to cooled wort for the benefit of the yeast.

Why aerate your wort?

Healthy happy (California) yeast make good tasting beer.

o    Too little dissolved oxygen results in

• Low and sticky fermentation
• Off flavors
• Poor yeast crop
• High ester production, resulting in a fruity-tasting beer
• Low alcohol production
• Better opportunity for unwanted wild yeast and bacteria to dominate wort

o    Too much oxygen causes

§  Rapid fermentations, resulting in excessive yeast growth and beer losses

§  Low ester

Yeast need to synthesize sterols (fatty acids) that are not normally available to them in the wort. When they have done this, their outer membranes are permeable thus allowing the sugars in the wort to be digested so alcohol and carbon dioxide can be created. Note: Olive Oil contains the very same fatty acid the yeast are trying to synthesize. Yeast can also use some trub to help in the synthesis of the needed sterols.

Fermentation and propagation\reproduction take energy. The yeast must build up their energy stores and grow\bud until they reach the proper density to start switching from aerobic to anaerobic metabolic pathway usage. Alcohol is a byproduct of anaerobic metabolic activity. Aeration helps yeast build up their initial energy stores to accomplish both of these main tasks.

When is the best time to aerate your wort.

• After the boil, once the wort has been cooled to pitching temp.
• Aerating the wort as it enters the chiller increases cold break and darkens the beer.
• Aerating wort with yeast already pitched into it can be beneficial depending on method of aeration
• After the wort has been fully cooled for lager fermentation and the settled trub has been removed or minimized.

When is the wrong time to aerate your wort?

• Aerating hot wort can set off staling reactions – some controversy on this theory
• After fermentation has already started as this can stall fermentation as the yeast switches back to aerobic metabolic pathways again. Need to be careful if racking to secondary.
• Aerating fermented wort can cause alcohol molecules to cause stale tasting aldehyde molecules.

 Aeration methods

• Splashing wort – easy and no cost
• Use of Venturi device – easy and minimal cost
• Oxygen stone with air pump in conjunction with a sterile filter – much quicker infusion of DO for a moderate cost.
• Oxygen stone with tank of pure oxygen - Very quick infusion of DO with slightly higher cost.
• Household Hydrogen Peroxide – very cheap but cannot be use in wort with pitched yeast Not Recommended! -  See Aeration Revisited

From Wikipedia:

On a given volume of air or liquid, the surface area changes proportionally with drop or bubble size, the very surface area where exchange can occur. Utilizing extremely small bubbles or drops increases the rate of gas transfer(aeration) due to the higher contact surface area. The pores which these bubbles pass through are generally micrometre-size.

Other things to consider

• One drop of Olive oil will give yeast all the fatty acids needed to develop permeable membranes, but does not help speed the development of energy stores.
• Aeration can be done multiple times in the first few hours after pitching yeast.
• Nearly impossible to surpass 8ppm DO unless pure oxygen is used
• Air is make up of only 21% Oxygen

How much to aerate the wort

·         Target is 8ppm to 12ppm of Dissolved Oxygen (DO). Varies by yeast strain and desired amount of esters contributed to the finished beer. To achieve 8ppm it takes:

• About 30 minutes of shaking a fermenter manually
• 15 minutes with air pump and aeration stone
• 20 seconds with tank of pure oxygen and aeration stone - 15 ppm in 80 seconds
• 2/3 to 1 ml of hydrogen peroxide per gallon of wort about 20 minutes before pitching yeast. Not Recommended! -  See Aeration Revisited
• You’ll get about 4ppm just by allowing cooled wort to drain into fermenter using a siphon spray attachment on the end of the hose.

My Recommendations;

• Clean\non-fruity  Ales (Most English and American ales) High DO (10 to 12),
• Med. Pitch Rate (1/2 gal. starter / 5 to 6 gallons wort) & Med to Low Fermentation Temp 70 to 64 degrees 
• Fruity Ales: Med DO, Med Pitch Rate (1/2 gallon starter pre 5 to 6 gallons of wort) &
• Med to High Fermentation Temp. (72 to 85 degrees
• Lagers: High DO (12+), High Pitch Rate (1 gallon starter per 5 to 6 gallons wort) &
• Very Low Fermentation Temp 40 to 50 degrees
• High Gravity beers; increase DO, increase pitching rate, use highly attenuative yeast strain, and allow fermentation temp to rise as fermentation finished, rouse yeast by swirling wort in fermenter as fermentation slows.
• Too much DO can actually kill all character from the yeast. Example – WL English Ale yeast with 5ml HO3 in 6 gallons and fermented at 66 degrees is nearly flavorless. Using 3.5 to 4 ml in the same size batch and fermented at 67 to 68 degrees is a nearly perfect balance while fermented at 74 the esters will dominate.

Pitch enough yeast, feed them and aerate them well and keep them in a cool dark place and they’ll reward you with a flavorful beer that has a balance of character from the raw ingredients and your hand in steering the yeast to add just enough of their own special flavors

 Once you master these basic rules you can start bending the rules to make truly unique beers!

Information Sources

• Books;
• Principles of Brewing Science (1^st ed.) by George Fix
• An Analysis of Brewing Techniques by George & Laurie Fix
• How to Brew (1^st ed.) by John Palmer
• Yeast by Chris White and Jamil Zainasheff

• Web Sites:
• Beer Advocate:  http://beeradvocate.com/forum/read.php?thread=588902
• The Brewers handbook  http://www.beer-brewing.com/beer-brewing/wort_cooling/wort_aeration.htm
• The Babble Belt  http://www.babblebelt.com/newboard/thread.html?tid=1108752780&th=1180990051&pg=1&tpg=1
• Thermofisher: Beer Brewing and Dissolved Oxygen .http://www.eutechinst.com/tips/do/09_DO_beer_brewing.pdf -

 Aeration and beer flavor

                Aeration is part of a pyramid that determines the majority of your beers flavor along with Pitching Rate and Fermentation Temp. These three components determine how your yeast will attenuate the wort and what flavor compounds they will contribute to your beer.

How temperature affects rate of oxygen going into solution from aeration

*You can see that it is nearly impossible to oxygenate very hot wort but the cooler your wort, the more susceptible it is to oxygenation.

How to calculate starter size to get the right pitch rate

750,000 x Volume in liters x Original Gravity in Plato

Example:

5.25  gallon of wort in your fermenter is about 20 liters.

If your O.G. is 1.061 that would be about 15 degrees Plato. 

750,000 x 20 x 15 = 225,000,000 yeast cells

Aeration Revisited

Four Methods Battle Head-2-Head

Oxygenation Revisited – Why

• Use of Hydrogen Peroxide was contested by club members with solid chemistry background.
• I’ve used Hydrogen Peroxide to make good beers, but too many had “unstable” flavor profiles.
• Summary article in Zymurgy on the initial experiment by Ron Cooper was against its use!
• Original article did not include blind tasting.
• Received in depth information on the use of olive oil at NBB by Grady Hull.

The Initial Experiment

• In original experiment included many beers that were entered in the 2004 Mayfaire homebrew contest
• Only those that used air pumps or pure O2 did well
• Those using Hydrogen Peroxide scored very poorly with comments about lack of malt or hop flavor and light body – called “two-dimensional” and “insipid”
• I was one of the judges at that contest when Ron first told me of his experimenting with Hydrogen Peroxide but I did not know about his final conclusions.

The New Experiment

• Make an Belgian-Style Dubbel with Chimay yeast
• Split the wort into 4 fermenters and then Oxygenate / Aerate via 4 different methods
• Pitch the same amount of yeast in each and ferment all 4 at the same temperature
• Ferment at high temperatures to develop esters and distinct yeast driven flavors in the beer
• Blind tasting – gather feedback on each before revealing which method was used on each sample.

 

·        Photos from the brew day - Beginnings

       

• Photos from the brew day                                                     The Key Players (aquarium pump, pure O2 and Peroxide)

 

 

•  Photos from the brew day – Divide & Conquer

 

• Photos from the brew day                                            Aeration in Action (aquarium Pump, shaking, pure O2)

 

 

 

 

 

• Photos from the brew day                                                    The 4 Musketeers

 

 

 

• Photos from the Fermentation                                            Day 1 @ morning (Already Cranking Good!)

  

• Photos from the Fermentation                                            Day 2 @ morning (at high kreusen)

 

 

• Photos from the Fermentation                                            Day 2 @ evening (already finishing on one batch)

 

• Photos from the Fermentation                                            Day 3 @ morning (finished on all but on one batch)

 

• Findings

• An Update on the use of Olive Oil by New Belgium Brewing Co.

From: Grady Hull

Sent: Tuesday, November 29, 2011 9:02 AM

 

Subject: Use of Olive oil instead of aerating wort

 

 

      Hi Shawn,

          I tested using olive oil as a yeast nutrient to replace wort aeration with the hope of improving the shelf-life of our beers.  The idea is that instead of giving the wort oxygen so it can remove a hydrogen from a saturated fatty acid, we give the yeast a monounsaturated fatty acid (oleic acid), with the hope that the reduced exposure to oxygen will result in better shelf-life.

              Unfortunately the gains we saw in shelf-life were minimal and did not justify putting in an elaborate olive oil dosing system.  I personally wouldn’t recommend it for home brewing since slight differences in shelf-life are less important.  The best thing we have found for keeping beer fresh in a bottle is still just to leave some live yeast in there.

              We use filtered air most of the time unless we are working with a difficult yeast strain, then we use O₂.

         Hope this helps,

         Grady

 

At the end of the experiment bottles of each version of the beer was presented at a blind tasting at Addison Homebrew Provisions. Ron Cooper was kind enough to drive over 40 miles to come to the meeting. The color, aroma and flavors that the 30-odd homebrewers could detect were noted during the blind tasting. At the end, a vote was taken and we found that while using an aquarium pump gave the flavors I was looking for, shaking the carboy was the most popular and gave the most malty flavors. Using pure O2 was good, but not nearly as popular as the others and using hydrogen peroxide was a complete disaster. Ron Cooper believes in using no additional oxygenation (other than spashing into the fermenter) in order to achieve the best flavored beer.

Updated 1-18-13: Here are the flavors and aromas that were thrown out during the blind tasting at AHP.

 

Fermenter #1 – Aquarium Pump

Sweet ,Fruity ,Citrus ,Peppery ,Bready chewiness ,“Belgian” Esters . Slightly lighter color than #2 or #3

Fermenter #2 – Peroxide

Dry ,Bitter ,Carmel sweetness ,Thin body ,Flat finish ,Few Esters
 

Fermenter #3 – Pure O2

Creamy ,Malt sweetness ,Less Fruity than #1 ,Hot – Alcoholic ,Phenolic from pepper & alc. ,Slight sourness at finish ,Some caramel flavors, but less than #2

Fermenter #4 – Shaking

Viscous body ,Slightly darker color than 2 or 3 ,Lots of sweet maltiness ,Slight pepper ,Gentle hops ,Mellow, English style esters – not the same as #1


Since the presentation, I've purchased an aquarium pump with dual outlets, two filter and two stones and my beer has never tasted better. Sometimes the simpler, more tried and trued ways of doing things turns out the best. Whe I revisit this topic I use a dissolved oxygen meter to dial in exactly how much O2 yields the best ester profile for some of my beers!

Thanks goes out to Nico for the extra carboys, Daniel for the use of his aquarium pump, Ron Cooper for taking the time to come to the meeting and his constant inspiration and AHP brew club member Unfrgvn82 for challenging me to prove my assumptions...good friends are like that!