Beer Geek 102 - Alpha acids

How do you get that just right amount of hops flavor and bitterness in your beer. It is not the amount of hops directly that matter, rather the amount of alpha acids.....

Alpha acids are a class of compounds primarily of importance to the production of beer. They are found in the flowers of the hop plant and are the source of hop bitterness. Alpha acids may be isomerized to form iso-alpha acids by the application of heat in solution. Iso-alpha acids are typically produced in beer from the addition of hops to the boiling wort. The degree of isomerization and the amount of bitter flavor produced by the addition of hops is highly dependent on the length of time the hops are boiled. Longer boil times will result in isomerization of more of the available alpha acids. The alpha acid "rating" on hops indicates the amount of alpha acid as a percentage of total weight of the hop. Hops with a higher alpha acid content will contribute more bitterness than a lower alpha acid hop when using the same amount of hops. High alpha acid varieties of hops are more efficient for producing highly bitter beers.
For example, this list shows a number of hop varieties with the highest percentages of Alpha Acids typically found in each variety (percentages are based on total dried weight). Alpha acid percentages may also vary within specific varieties depending on growing conditions, drying methods, age of the hop, and other factors.

• BULLION 11%
• CASCADE 8%
• CENTENNIAL 11.5%
• CHINOOK 14%
• CLUSTER 8.5%
• CRYSTAL 5%
• EAST KENT GOLDINGS 7%
• EROICA 14%
• FUGGLES 5.5%
• GALENA 14%
• HALLERTAUER HERSBRUCKER 5%
• HALLERTAUER MITTELFRUEH 5%
• LIBERTY 6%
• MT. HOOD 8%
• NORTHDOWN 9.95%
• NORTHERN BREWER 8%
• NUGGET 14%
• PERLE 9.5%
• SAAZ 5%
• STYRIAN GOLDINGS 7%
• SUMMIT 19.5%
• TARGET 12.5%
• TETTNANG 6%
• WILLAMETTE 6%

The next several postings will be all about hops. So strap on your taste buds. If you have any questions, comments or stories, please share with us. And don't forget for you budding gardeners out there hops rizomes come out mid to late March. pearlcitysobs@yahoo.com.

Beer Geek 101 Word of the Day - Zymurgy

Not only is this a great scrable word worth a ton of points. It is a term near and dear to the hearts of all home brewers. Zymurgy is the study of fermentation. So many things can affect fermentation that it truly is a science. Some of the things that affect fermentation that are critical for the homebrewer to understand.....
     Temperature: typically warmer temps bring on faster fermentation, but ever yeast strain has a range at which it will reproduce and thrive.
     Yeast strain: see above
     Alcohol content. Some beers can only ever be a certain percent alcohol because going above this percentage is toxic to the yeast and therefore fermentation stops.
     Contamination: If forced to compete with contaminating bacteria the yeast can lose and the outcome is not good (usually), lambics is a type of beer that purposefully introduces a certain bacteria to provide a certain taste. I am a big fan of Frambois - a French lambic.
     Light: the darker the better. A closed room in a basement or a closet are your best bets.

If you have any questions, thoughts or stories about fermentation please comment below, let us at the Pearl City Society of Brewer's know about it, below or at pearlcitysobs@yahoo.com.

Beer Geek 101 - Keg Volumes

U.S. keg sizes Most U.S. brewers sell beer in 1/2 barrels between 14 and 16 gallons, 1/4 barrels between 7 and 8 gallons, and 1/6 barrels between 5 and 6 gallons.
Since keg sizes are not standardized, the keg cannot be used as a standard unit of measure for liquid volumes. This size standard varies from country to country and brewery to brewery with many countries using the metric system rather than U.S. gallons.

A typical keg (half-barrel) with single opening in the center of the top end

A full keg is a 15.5 U.S. gallon barrel, routinely called a half-barrel. A Quarter Barrel has a volume of 7.75 U.S. gallons. Generally a keg is a vessel smaller than a barrel; thus, it is 30 gallons or smaller.
In the U.S. the terms half-barrel and quarter-barrel are derived from the fact that a U.S. beer barrel is legally defined as being equal to 31 U.S. gallons (note that this is not the same volume as some other units commonly known as barrels). A 15.5 U.S. gallon keg is also equal to:

• 12.7 Imperial gallons
• 58.67 liters
• 103.25 Imperial pints
• 124 U.S. pints
• 165 twelve fluid ounce (U.S. measure) drinks
• About 90 bombers
• About 6.88 24-unit cases of 12 fl oz cans.
• About 5.5 30-racks of 12 fl oz cans.
• 1984 fluid ounces (U.S.)

However, beer kegs can come in many sizes, the typical home brewer uses a "Corny Keg." typically these are old converter soda syrup kegs and hold 5 gallons.

Beer Geek 101 - The Basic Nomenclature

Mash
     Mash is the grains soaking in the water, soaking the sugars out of the grain.

Wort
     Sweet Wort = The solution of grain sugars strained from the mash.
     Brewed Wort = During and after the boiling. This is when hops are added, they are added at various times in the boil. Some spices and flavorings can be added at any pont in the boil, but typically at or near the end of the boil
     Fermenting Wort = After the brewed wort is chilled, the addition of yeast and sometimes priming sugar and or olive oil makes a perfect breeding environment for the yeast. The yeast eat the sugar and replicate and give off ethanol and CO2 as byproducts. This can take a few days to several weeks depending on temperature, type of yeast, etc...

Carbonation
     Bottling: Carbonation can be done by the yeast in a bottling system as the fermented wort is siphoned off into bottles then priming sugar added and the bottle capped off. The yeast will make more alcohol and CO2 is a byproduct.
     Forced carbonation, although more expensive than bottling saves quite a bit of time and effort. Place your fermented wort in a keg, pressurize with CO2 and you can be drinking your beer in a few days. This takes special equipment but in my estimation will increase your enjoyment of the process.

Beer!
      To borrow a few descriptors: the fruit of the labor, the nectar of the gods, proof that god loves us and wants us to be happy!

Home brewing is such a beautifully simple thing, we just assign an entirely new language to it and it can be unnecessarily intimidating. Do not let it intimidate you. As Charlie Papazian (Sorry Charlie if I spelled your last name wrong) would say, "relax have a home brew."

As always any questions or concerns or comments are welcome at pearlcitysobs@yahoo.com, or by commenting below.

Beer Geek 101 - Degrees Lovibond, Measuring the Color of Beer

"Degrees Lovibond" or "°L" scale is a measure of the colour of a substance, usually beer, whiskey, or sugar solutions. The Standard Reference Method (SRM) and EBC method have largely replaced it, with the SRM giving results approximately equal to the °L. The determination of the degrees lovibond takes place by comparing the color of the substance to a series of amber to brown glass slides, usually by a colorimeter. The scale was devised by Joseph Williams Lovibond.^[1]
The Standard Reference Method or SRM ^[2] is a system modern brewers use to measure colour intensity, roughly darkness (but see Tristimululs Color below), of a beer or wort. The method involves the use of a spectrophotometer or photometer to measure the attenuation of light of a particular wavelength, 430 nanometers, as it passes through a sample contained in a cuvette located in the light path of the instrument.

Colour based on Standard Reference Method (SRM)

SRM/Lovibond	Example	Beer color	EBC
2	Pale lager		4
3	German Pilsener		6
4	Pilsner Urquell		8
6			12
8	Weissbier		16
10	Bass pale ale		20
13			26
17	Dark lager		33
20			39
24			47
29	Porter		57
35	Stout		69
40			79
70	Imperial stout		138

      O.k. so this is not so practical of a scale, I have yet to attend a casual brewers meeting in which this was a hot topic, usually you hear color talked about in a much more general way. But you will see the SRM or L scale at the beginning of some recipes and it is worth knowing what you are going to get yourself into before you start brewing, Any questions or comments on describing the color of your beer, please contact us at Pearl City SOBs, or leave a comment below.

Home brewing with a green thumb

Want to give your love for home brewing a natural twist? Consider planting and growing your own hops. This member of the hemp family quite literally grows like a weed here in the midwest. All it needs is a lot of sun and a lot of space. For those of you who don't know this plant can grow in excess of 20 feet. My solution to this fast growing plant...

I mounted a pulley to the apex of my garage. A rope attached to a board with ropes going down to the base of my plants. When it comes time to harvest the hops I just lower the board down to ground level. Once the hops get growing you have to direct the plant by wrapping the feelers the plant puts out around the rope so it grows in the right direction.

For those of you who have never brewed with whole hop flowers, not just pellets, beware displacement, because the flowers occupy a lot more volume. Get out your larger brew kettles!

I get my rhizomes from Jerry at the Bluff Brew Haus in Dubuque, IA. If you live anywhere in the Dubuque area I highly recommend you check out  his store - he is a great guy and a great resource.

If there are any brewers out there with a green thumb with any tidbits to share on growing or using hops, please share with us here at PCSOBs.

Waste Not, Want Not

What to do with the sludge at the bottom of your wort? Hops, we all love them. But when I started the homebrewing process I was told to take great care to avoid getting the hops sludge at the bottom of your wort into the fermentation carboy. A sentiment I have heard several times over the years.
     I have found that including the sludge does not harm, and in some cases has actually improved the flavor of my beer, especially those extra hoppy IPAs. Now this may be my bias as I am partial to hoppines, in fact I have yet to meet a hop I don't like.
     PCSOBs is curious about your opinion in the matter, post a comment or e-mail us and let us know what you think.

Avoid Buying an Aeration Stone and Oxygen Tank

     So here is a little tidbit for you home brewers:  avoid the temptation to get really geeked out learning about surface tension and bubble physics.You do not need to add oxygen to jump start your yeasties. If you want to give them a head start to reproduction all it takes is one drop of extra virgin olive oil to 5 gallons of wort (yes I said only one drop). I add it after the wort has been chilled.
     Of course if you want to geek out - then by all means, geek away. Half of all the fun is trying new things. But be wary of the aeration stone and the potential for contamination.
    Like this tidbit? Agree/Disagree? Let us at PCSOBS know at pearlcitysobs@yahoo.com.