Hapa's Brewing Company

Blog

By in Brewing 0

A Delicate Balancing Act

Warning: Science content below!

The beer has been brewed, it’s been carbonated, and the kegerator has been made.  All that’s left is to pour yourself a glass.  It seems like a simple thing: pull the tap handle and have beer flow into a glass with a perfect frothy head.  However, like many things, this is easier said than done.  For beer to pour properly from the tap, the draft system must be balanced.

There are several factors that need to be considered when balancing a system.  All of these factors ultimately affect the way beer will pour out of the tap:

  • The temperature of the beer
  • The beer’s level of carbonation
  • The CO2 pressure kept in the keg
  • The length and diameter of the beer line
  • The height the beer must flow to reach the faucet

The first step in balancing a draft system is to determine the level of carbonation for the beer.  The level of carbonation depends on the style of beer, but is ultimately based on opinion.  As mentioned in The Great Carbonation Debate, beer is force carbonated by first cooling it and then adding CO2 at pressure. Click here to view a chart that outlines the level of carbonation achieved with a given temperature and pressure and the recommended volumes of CO2 for a given style.

The pressure needed to properly carbonate beer is an important number.  Not only is this pressure keeping the beer bubbly, but it is also going to be used to force beer up the lines and out the faucet.  The concept behind balancing a draft system is to drop nearly all of that pressure in the time it takes for the beer to travel from the keg to the faucet leaving just enough to get the beer to flow out.

There are several forces that work against the pressure exerted by the CO2 in the keg.  These are gravity, the length of the beer line, and the resistance of the beer line.  We can create a formula that describes how the pressure from the keg (measured in PSI) will be affected by these factors:

P = Pressure of CO2 in keg (in PSI)
H = Height from middle of keg to faucet (in feet)
A = Pressure lost per foot of height due to gravity (in PSI/foot)
L = Length of beer line (in feet)
R = Pressure lost per foot of beer line due to resistance (in PSI/foot)

Essentially what we are doing in this formula is subtracting PSI lost due to gravity and the PSI lost due to the resistance of the beer line from the pressure in the keg.  If the net of this equation was zero, there would not be enough pressure to get beer to flow from the faucet.  There needs to be at least 1 PSI left to get beer to flow, so we set the equation equal to one:

Time to fill in some of these numbers: Gravity accounts for a .5 decrease in PSI per vertical foot the beer must travel and in my system the height is 2.75 feet.  The resistance of the beer line depends on its inside diameter.  For 3/16″ beer line (which is what I use) we will lose an average of 1.8 PSI per foot.  The pressure of my keg is 9 PSI which at 38 degrees gives me a carbonation level of 2.3 volumes.  Plugging these numbers into my equation I can figure out how long my beer line should be to have a smooth pour.

Solving for L (assuming my math is correct), I get 3.7 feet of beer line is needed.  The tower came with 5 feet of beer line, so I just cut away what I don’t and reattach the liquid out ball lock disconnect.  Just in time too, after all that math and science, I need a beer!

By in Other 0

Not a Bad View

No one will ever argue with the statement: “San Francisco is a beautiful city.”


View of the Golden Gate Bridge at sunset on 11/4/2010

By in Brewing 0

The Great Carbonation Debate

The final step in brewing beer (aside from drinking it!) is to carbonate it.  You would be hard pressed to find someone who enjoys a flat beer.  Carbonation gives beer a light and refreshing feel in the mouth when consumed and also enhances flavors and aromas.  The questions is: how is beer carbonated?

As I eluded to in The Final Countdown, there are two ways to carbonate beer: force carbonation and natural carbonation.  Both have their advantages and disadvantages:

Natural Carbonation

To naturally carbonate beer, a small amount of sugar (called priming sugar) is added to the beer after fermentation has completed.  The beer is then put into bottles, growlers, kegs, etc. and sealed.  Residual yeast will then ferment this sugar and produce alcohol and CO2.  Because the vessel in which the beer is being held is sealed, this CO2 dissolves into the liquid thereby carbonating the beer.

Advantages:

  • Some people say that natural carbonation results is a thicker head, smaller bubbles, and more lacing (lacing is the ringing of foam around a glass that is left when the head dissipates.  It is considered a good thing.)
  • It requires less equipment than force carbonating
  • It’s traditional and all natural

Disadvantages:

  • It takes longer to carbonate your beer.  Beer that has been naturally carbonated needs an additional 2-4 week for fermentation and conditioning to take place
  • If too much sugar is added, beer can be over-carbonated or bottles can explode
  • More yeast will settle on the bottom of the bottles which doesn’t look pretty

Force Carbonation

To force carbonate beer, it is transferred to a keg where it is chilled.  CO2 is then pumped into the keg and kept at pressure.  Over the course of a few days this CO2 will dissolve into the beer carbonating it.

Advantages:

  • It takes much less time to carbonate beer; only 3-7 days
  • Results in cleaner looking beer
  • Takes guess work out of adding priming sugar
  • Doesn’t result in added yeast flavors in the final product

Disadvantages

  • It requires expensive equipment
  • Can result in a head that is less billowy and has worse lacing
  • Deviates from the all natural brewing process

 In the end how beer is carbonated is a matter of personal preference.  I happen to have all the equipment I need for force carbonation, and combined with my lack of patience, results in my preference of force carbonating beer.

By in Other 0

One ‘Giants’ Leap for Mankind

Today was a special day in San Francisco.  It was a day for the entire city to come together and celebrate with our hometown team: the World Champion Giants.  The Giants ticker-tape parade marched through downtown San Francisco and I was lucky enough to have a front row seat for the show.  It was an incredible sight to behold as 100,000+ plus people lined Market Street to cheer on the team.  All I had to do was put on my Giants hat and I instantly had 100,000 new friends.

            
Montgomery Street                                                              Market Street

Some highlights of the parade included seeing the “Say Hey Kid” Willie Mays, Bruce Bochy with the World Series trophy, and San Francisco Mayor Gavin Newsom.  I actually made eye contact with the mayor and gave him a thumbs up that even he would be proud of. 

        
Willie Mays                                                                    Bruce Bochy

Gavin Newsom

Of course the grand finale of the parade included the entire team.  From my vantage point above Market Street I saw all familiar Giants faces: Cody Ross, Matt Cain, Buster Posey, Brian Wilson.  I also saw the faces of all the Giants no one knows, whose names I’ve already forgotten but cheered for anyways!

        
Cody Ross                                                                       Buster Posey

By in Other 0

Giants = World Champions!!!

The Giants won their first World Series since moving to San Francisco in 1957!  It seemed like the entire city was pulling for this team and last night it seemed like the entire city was drinking for it!


Chestnut Street, San Francisco, CA

Sorry for the poor picture quality, I had to use my phone.

Watching Tim Lincecum dominate the Rangers begs the question: can he throw a football as well as he throws a baseball?  The 49ers need the help!

By in Brewing 0

The Final Countdown

This weekend was Halloween which meant it was time for candy, costumes, and of course beer!  Between some great football games and the World Series, I was able to transfer the Brown Ale to the keg.  The process is very similar to the one used when moving the beer to the secondary fermenter; using an auto siphon to carefully transfer the beer. 

        
Glass carboy and 3 gallon keg                                 Siphoning beer to the keg

The next step is carbonating the beer.  There are two methods for carbonating beer: natural vs. forced.  The difference / advantages / disadvantages of these two methods will be discussed in a future posting, but because I have a draft system and because I don’t have enough patience to wait for natural carbonation, I have chosen to force carbonate my Brown Ale.

The process of force carbonation begins with cooling the beer down as gasses dissolve easier in liquids at lower temperatures.  Once the beer has been cooled, CO2 is pumped into the keg at kept at a pressure of around 10-12psi.  Over the course of a couple days, the CO2 will dissolve into the beer and an equilibrium will be reached.  At that point the beer is ready to be enjoyed!


Keg at CO2 tank in the fridge

As you can see, I keep my draft system in a mini fridge.  This set up works for now, but I’m planning on coverting the fridge to a kegorator… stay tuned!

By in Other 0

Life’s Three ‘Bs’: Beer, Barbecue, and Baseball

While the focus of this blog if beer and barbecue, there are other things that need to be enjoyed in life.  Yesterday was a great example of that philosophy.  October 27th, 2010 was a very eventful day for me.  I knew ahead of time that it was going to be an extraordinary day, but I wasn’t prepared just how exceptional it would be.

The day started out with a World Series tickets on the line.  It’s not every day that one has the opportunity to see his or her hometown team play on the biggest stage in their respective sport, but that is exactly the position I found myself in.  To win the tickets I would need to compete in America’s other pastime: Corn Hole.

It was do or die; one ticket, two people, and a best of three match.  The competition was fierce.  Back and forth the scores went and it all came down to a third and final game to determine who would get the ticket.  This wouldn’t be much of a blog entry if the story ended there, so you’ve probably already guessed that I emerged victorious.  I was elated!

At 4:00pm I made my way down to the stadium to meet the rest of my party.  While waiting by the Willie Mays statue, I was treated to pleasant surprise: a complete stranger came up to me and informed me that I look a lot like Giants backup first baseman and fellow hapa, Travis Ishikawa.

        
Travis Ishikawa                                                             Willie Mays statue

My friends showed up shortly thereafter and we made our way to our seats.  The seats were fantastic; lower deck, down the first baseline.  The place was packed and the atmosphere: electric.  Two of the games greatest pitchers were about to square off, and I couldn’t help but think of the other great match up from the day: me vs. my friend on the Corn Hole pitch.

        
The view from my seat                                                        Tony Bennett sang I Left My Heart in San Francisco

The game however, did not start out well for the home team Giants.  Trailing 2-0 after the first inning, things were not going well, but Giants came alive in the third tying the score at 2.  In the fifth inning something magical happened.  Yes, the Giants scored six runs, but this thing did not happen on the field.  After enjoying a few Sierra Nevadas I needed to take a bathroom break.  Lines for the restroom can be very long so I was worried about missing the game.  With two outs, I decided to make a move.  I devised a clever strategy.  The Giants had runners on first and second with Juan Uribe at the plate.  Everyone else in the stadium was glued to their seats as the Giants continued to rally.  The line at the bathroom was nonexistent.  It was also at that moment the Rangers decided to make a pitching change giving me just enough time to make it back to my seat to see Uribe launch a ball deep in the the left field stands.  I had just completed the greatest bathroom break in sports history!

The Giants went on to win the game by a final score of 11-7.  Three more games and the Giants will bring our first World Series Championship to San Francisco!

By in Cooking 0

Keeping the Napkin Industry in Business

Here we are on Monday morning and after showering last night AND this morning, I still smell like a campfire.  A telltale sign of a good weekend! 

Hapa’s Brewing Company went on the road over the weekend.  Naturally we were accompanied by the Weber Smokey Mountain Cooker and naturally we make a stop at Cash & Carry on the way out.  This time around we would be cooking pork loin back ribs, better known as baby back ribs.  Baby back ribs come from the top of the rib cage between the spine and spare ribs.

           
                Pork rib diagram                    Bone side of back loin ribs                             Meat side of back loin ribs

At Cash & Carry I was able to find a Cryovac pack of three slabs of baby back ribs totalling 8.4 pounds.  I prepped all three the same way.  First, I removed the membrane from the bone side of the ribs.  This membrane prevents the rub and smoke flavors from being imparted into the meat and does not make for good eating.  I also removed any large pieces of fat from the meat side of the ribs.

        
Removing the membrane                                 Fat removed

Next, I applied the rub that consisted of: sugar, salt, brown sugar, chili powder, cumin, cayenne pepper, black pepper, granulated garlic, and onion powder.


Rub applied

For this cook I fired up the cooker by lighting a full chimney of briquettes and adding another full chimney on top of that.  I used four chucks of oak and two of apple for my smoke wood.  When the cooker came up to 225 degrees I added the ribs.  In order to get the ribs to fit onto the cooker and to promote even cooking, I rolled the ribs and used a wooden skewer to hold them in place. 


Out of the house and onto the fire

I kept the cooker in the 250-270 degree range for the entire cook and after four hours I checked on the meat.  To check for doneness I gave the ribs a pull.  They meat came right off the bone, and I knew it was time to eat!  After unrolling the racks and divvying up portions, everyone added their favorite barbecue sauce and ate.  One hour, 40 sticky fingers, 200 napkins, 4 sauce covered faces, and 4 smiles later we were done. 


Out of the fire and into the mouths!

By in Brewing 0

Fermentation: Fun Enough to do Twice!

It has been a week since the Brown Ale went into the fermenter which means it’s time to transfer the beer to the secondary fermenter.  I use a glass carboy for secondary fermentation.


Glass carboy and siphon

Secondary fermentation is not a necessary step in the brewing process, but it definitely has some advantages.  During primary fermentation dead yeast, proteins, and other particles like bits of hops settle to the bottom of the fermenter forming a layer call the trub.  Separating the beer from this layer prevents unwanted flavors from being imparted into our beer.  Allowing all these particles to settle out will also result in a clearer final product. 

When transferring beer from the primary to secondary fermenter, it is important to minimize the beer’s exposure to air.  Extended exposure to air or excessive slashing can lead to oxidation of the beer.  Oxidation can lead to off flavors or a stall in the fermentation process.  To minimize slashing and exposure to air, I use an auto siphon and to control the flow of beer I pinch the line with a clamp.


Siphoning beer

After transferring all the beer it is important that the carboy go back into a dark area with a stable temperature of 65-75 degrees.


Full carboy

One more week to allow the beer to condition and clarify.  Let the countdown begin!

By in Brewing 0

Ales vs. Lagers

Beer comes in a wide variety of styles, colors, and tastes.  Some are full bodied and have strong hop flavors, while others come in a can with a wide mouth and vent to help it pour down your gullet faster.  What is it that distinguishes one beer from another?  At the highest level, differences in beer styles come from the strain of yeast that is used during fermentation

 

There are two kinds of yeast used in beer making: ale and lager.  There are several differences between these yeast varieties that impact the brewing process and final product.

 

Temperature:

Lager yeast prefers a lower temperature while it ferments sugars to alcohol.  If you’ve ever heard the slogan “Frost Brewed,” you’re drinking a beer made using lager yeast and are probably drinking out of a can with blue mountains.


 

Time:

The lower temperature of the fermentation process means it takes longer to complete.  Where primary fermentation for an ale might be one week, a lager can take up to three.  Lager needs a longer time to condition as the yeast produces more sulfur based compounds.  These compounds can impart a bad smell and taste to the beer and need time to vent off and be broken down by the yeast.

 

Taste:

Lagers are characterized by their clean, crisp taste.  Some might call it “drinkability.”  This is opposed to ales whose fruit flavors and full bodied feel are a result of warmer fermentation temperatures and increased bittering hop usage.

 

Top vs. Bottom Fermenting:

Lager yeast is bottom fermenting, meaning it sits at the bottom of a fermenter during the brewing process.  Ales yeast do just the opposite, fermenting sugars at the top of the fermenter. 


Fermentation Tanks
 

Lager is the America’s most popular style of beer.  You are very familiar with American Lagers as they are produced of the most famous names in beer including Budweiser, Coors, and Miller.  You have undoubtedly enjoyed a lager… or ten… while watching football on Sundays.  Now you will able to impress your friends with an Alex Trebek like knowledge of beer!