Secondary Fermentation Dry Ice CO2 Purge

Oxygen contact is bad news for homebrews.  Once you pitch your yeast into the fermentor, you want to keep contact with oxygen at a bare minimum.  You need a little bit of oxygen to help the yeast reproduce and be happy at the beginning of the process (which is usually incorporated by aeration), but producing alcohol is an anaerobic process for the yeast.  That means oxygen can stall or stop the fermentation process (not to mention, if you have contamination in your fermentor from poor sanitation practices, oxygen will help the nasty stuff grow).

For the primary fermentor, your yeast are actively creating CO2 and displacing the existing oxygen in the container, so you don't have to worry about purging it.  However, in a secondary fermentor, a CO2 purge would minimize the risk of oxidization of your beer and contamination.

We learned a cool trick from our local homebrew store using a funnel and dry ice, and thought we'd share it here!

Quick reminders:

• Remember to use good gloves and/or tongs when handling dry ice! 
• You only need a small block--maybe the size of a full wallet or a deck of cards.
• Check your dry ice for dirt, and use a sink brush or sponge to quickly clean it.

Check your funnel for a small notch in the stem--this method will only work if there is a way for your purged gas to exit.

Place the sanitized funnel into your carboy, and carefully place a small amount of dry ice in the funnel.  

 

Since CO2 is heavier than air, the CO2 will sublimate off the dry ice, travel down the funnel, and displace the air out of the carboy through the stem notch.  Let the sublimating CO2 purge until you see the condensed air (what looks like fog) come out of the stem notch.  

Be careful when removing the funnel: water frost will form on the outside of the funnel, and you don't want to accidentally shake or knock this into your fermentor!

 

Making a Wort Chiller

You only need to brew once to understand the value of a good old-fashioned heat exchanger!

After boiling all of the ingredients, the wort needs to cool to a temperature that won't kill yeast.  The tricky part is doing this in a truly clean fashion, and many new brewers are forced to use the kettle-in-an-ice-bath method.  The first time we brewed, it took us over an hour to cool our wort, since our bathtub was so huge and we didn't have enough ice.  In our new apartment, our brew kettle fits snuggly in the kitchen sink, which allows for frequent water bath changes and a wort cool down to happen in about 45 minutes instead.

This last month, Ryan took the initiative to fashion a homemade wort chiller.  Time for a science explanation!  A wort chiller is essentially a heat exchanger.  The idea is that the cold pipe and hot fluid will "exchange" energy, thus cooling your fluid and heating up your pipe.  We used a 25-ft copper coil because the more surface area you have, the more heat you can exchange through the pipe.  Additionally, copper has a high thermal conductivity, which means heat transfer occurs at a faster rate than materials with a low thermal conductivity (like air).  To keep the copper pipe at a much lower temperature than the wort, you run cold water through the coil to keep the heat exchange at a high rate.  This homemade chiller brought our wort cool down time to < 20 minutes.

The best part?  Ryan spent ~$30 on materials and a few hours in one day, and I bet we could have spent less if we did some deal-searching online/in town.  If you go to a homebrew store to buy a commercial wort chiller, they can run at least $60.

We purchased our materials from local hardware shops, but I linked some of the materials to Amazon.com so you can see the pictures.  Of course, it is best to have the pieces in hand to make sure everything fits before you go to put it all together.

Materials:

• 25 ft coil of copper pipe, 3/8" outer diameter
• 1 Tubing bender for 3/8" tube
• 6 ft clear plastic tubing, 3/8" inner diameter (you may need more or less, depending on your source of water and dumping sink) 
• 3 worm drive hose clamps + 1 flathead screwdriver
• 1 dual thread faucet to hose adapter (make sure your faucet is threaded and compatible!)
• 1 hose thread to 3/8" barb adapter

Take out your boiling kettle and make sure the copper coil can fit inside.  Slip the tube bender over the pipe, and use your hands to shape a 90-degree bend such that ~8 inches of the tube protrudes over the top of the kettle.  Bend another 90 degree bend at the top of that leg, such that the pipe is parallel to the ground.

Repeat this with the other end of the pipe.

Cut your plastic tubing in half.  Affix each piece to one end of the copper pipe, and secure in place with a worm drive clamp.

 

With one of the plastic tubes, push the hose-to-barb adapter into the tube and secure with another worm drive clamp.

Screw the faucet-to-hose adapter onto the other side of the hose-to-barb adapter.

 Remove any sort of cover from your faucet of choice, and attach the faucet-to-hose adapter to your sink faucet.

Place the wort chiller in your kettle, and route the free plastic tube to a drain (we used our bathtub).

Now turn your faucet as cold as it will get, and watch your wort cool at record speed!  

Spooked Out Stout (Beer #1)

Back in October, Ryan and I invested in a homebrew kit in celebration of his new job.  We've been having a lot of fun in the process, and drinking your own homebrew is such a rewarding experience.

Our local brew shop in Seattle is Bob's Homebrew Supply, and the staff there is incredibly friendly and helpful!  We decided winter was a good time to warm up with a thick, dark, imperial stout.  We've recruited the help of our friends Sarah and Lenny, and the only photos I have from this first brew session involves no beer at all:

Digby loves brew days!

Unintentionally so, the beer was ready to drink on October 31st...which gave us the idea to name it "Spooked Out Stout" in honor of Halloween.

The fermenter

The recipe is from Bob's, and yields 5 gallons.

Ingredients needed:

• 12 oz roasted barley
• 4 oz black patent malt
• 7 lb amber malt extract (wet)
• 2 lb dark malt extract (dry)
• 30 AAU Magnum hops (55 min)
• 1 oz Centennial hops (5 min)

1. Boil 3 quarts of water to 165-170°F.  Meanwhile, preheat oven to lowest setting (~200°F)
2. Stir in the grains (barley and black patent malt), remove pot from heat, and steep covered in the oven for 30-45 min.  
3. Meanwhile, bring 2.5 gallons of water to boil in the brewing kettle.  Once boiling, add malt extracts (wet and dry) and stir well.  Lower temperature and keep stirring to avoid boil over.
4. Separately boil 2 quarts of water to 160-170°F.
5. Using a metal sieve, strain the grain mixture into the boiling kettle, and pour the boiled 2 quarts of water over the sieve (sparge the grains).  
6. Return the kettle to boiling, and add Magnum hops.  Boil for 55 min.  Get the ice bath ready.  
7. After 55 min has passed, add the Centennial hops and boil for 5 min.
8. Turn off heat, and put the kettle in the ice bath.  Stir once every 5 min, leaving the spoon in the kettle, held upright by the ajar lid on top.  This will minimize the chances of contamination.  Stir until < 80°F.
9. Strain mixture into the sanitized fermenter, and add enough cold bottled water (or boiled-then-cooled tap water) to add up to 5 gallons total (should be ~1.5 gallons).
10. Attach the lid and the airlock, and ferment for about 2 weeks before bottling.
11. Follow your own preferred secondary fermentation/bottle conditioning method, but we did 152g of dry malt extract in 2c of boiling water for a primer solution.  We boiled for 15 min, cooled to 80°F, mixed with the beer, and bottled.