Happy Brew Year! Today I'm going to brew a simple Mexican-style dark Lager which traditionally were based on a Vienna dark lager but with US ingredients including flaked corn. In this thread I will document my brew day.

The first step is to heat up my mash water. I brew beer using a Grainfather brewing system, which automates a lot of the process for me and shaves a few hours off of my brew day.

While the mash water heats up, I grind my grain using a hand grinder. For some recipes I get my malted barley pre-ground, but I have started buying my base malt in bulk, and the barley comes whole.

Grinding the grain removes the kernel from the husk and exposes more of the starch to the water so the mashing process is much more efficient. Malted barley contains an enzyme that will convert starches in the barley to sugar when immersed in water.

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After the water heats up I can "dough in" or add my ground grain to the mash water. I have a long metal mashing paddle that makes it easier to stir the grain as I add it to remove clumps, which helps improve mashing efficiency later. Basically you are making a barley porridge and the consistency at the end is pretty similar to oatmeal.

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Once all the grain is added I add a mesh screen above the water level in the kettle, attach a recirculation arm to my Grainfather's pump and tell it to start the 90 min mashing process. It recirculates water throughout the process to improve efficiency and clarity in the beer.

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During this 90 minute mashing process enzymes in the malted barley convert starches into simple sugars like alpha and beta amylase. The ideal temp to convert each of these sugars is different, so recipes pick temps somewhere in the middle based on which sugars they want the most of. This choice can affect the body and residual sweetness left in the beer after fermentation.

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Even though I need to wait 90 minutes for the next step of the process, I'm not sitting here idle. A key part of having an enjoyable brew day, I've found, is to clean up incrementally during these down times, and prepare everything for the next step. For instance, after I started the mashing process, I put away all of the grain grinding equipment and my bag of bulk barley, swept loose grain from the floor, and now I'm preparing my lauter tun for the next step.

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After mashing, the next step is the lautering process, where I remove the grain from the mash water and rinse it with hot water to extract more remaining sugars.

This is my lauter tun. It's an electric brewing kettle that I used to brew beer with before I got my Grainfather. I fill this kettle with the appropriate amount of water, heat it to the proper temp, and then connect a hose to a spout at the bottom and use gravity to move the water to my Grainfather.

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After mashing, I lift the interior metal basket and rest it at the top of the Grainfather. There is a mesh at the bottom of this basket which allows the sticky, sweet brown liquid called wort to drain into the kettle while leaving the grain behind.

While the kettle heats up to boiling, I start rinsing the top of the grain with hot water from my lauter tun. This water trickles through the grain bed and extracts more sugars as it drips down into the kettle.

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The lautering/sparging process is complete so I removed the top grain basket and now we are waiting for the wort to reach a boil. What do we do while we wait? We clean of course! I dumped the spent grain into the compost bin and cleaned the grain basket and lauter kettle and all mashing and lautering equipment. In a minute I will start stirring the foam at the top of the kettle back into the wort so it doesn't boil over when it hits boiling temps.

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We are about 30 minutes into a 90 minute boil. If you look closely at this picture you can see light tan bits that aren't foam, that seem to be floating to the top. This is known as "hot break" and are proteins that are cooking out of the wort during the boil. This is something we want to happen and is one of the reasons for the boil.

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Now for the first (and for this recipe only) hop addition with 60 minutes left in the boil. These are whole leaf Cascade hops that we harvested from our hop plant in our garden this summer.

Adding hops at this stage of the boil extracts compounds that make the beer taste more bitter. These compounds are also anti-microbial and help protect the beer from infection post-boil, especially in the sensitive stage before the yeast make any alcohol.

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The boil is done so I've attached my counterflow chiller to my Grainfather pump and I'm recirculating boiling wort through it for 10 minutes to sanitize the inside of it before I connect it to cool water to actually chill the wort. I also filled my fermentation vessel with sanitizing solution for 10 minutes so it will be disinfected when I'm ready to transfer wort to it.

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The counterflow chiller is a heat exchanger with two inputs and two outputs. Hot wort is pumped through one input and exits back into the kettle. The blue tube is an input attached to a cool water source (garden hose) and the red tube is the output of that water source. As the hot wort and cool water flow through the chiller, the heat is exchanged, cooling the wort and heating the water. I collect the hot wastewater and re-use it for cleaning the kettle later.

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With enough cool water flowing through the system, the counterflow chiller can chill the wort enough to go into the fermentation vessel (plastic carboy) within a few minutes. I have an in-line thermometer I use to monitor the temperature of the wort leaving the counterflow chiller and when it's within the right range I stop the pump, move the wort output to my carboy, and start the pump again, pumping the cool wort into the carboy.

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As the wort pumps into the carboy, I redirect a bit into a cylinder so I can take a gravity measurement (in this case I was right on target: 1.050!). This measures the specific gravity of the liquid compared to plain water and approximates the amount of sugar you have in your wort. Later when the beer is done fermenting I will take another reading and use the difference to determine how much sugar was converted into alcohol.

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With the last bit of wort pumped into the carboy, I pitch my yeast, add an airlock to the top, fill it with vodka, and the brewing process is done. I will move the carboy to a temperature-controlled chamber where it will ferment for a few weeks, then lager for a few more weeks, before I transfer it to a keg.

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All that's left is for me to clean my equipment. With the Grainfather this means pouring some water into it, adding some brewing cleaning (PBW in my case) heat the water, and then pump it through it and the counterflow chiller for 10 minutes, replace with fresh water, and then rinse for 10 minutes.

Thank you everyone who stuck with the thread to this point. It was fun sharing the brewing day with everyone. Feel free to post any questions you may have.

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Beer Update: It's alive! The first few days the beer was perfectly still with no sign of life (the yeast were reproducing), but now a week in you can see bubbles on the top and the airlock is bubbling away. This means the yeast is alive and happily converting sugars into alcohol and CO2.

This is a lager yeast so it will hang out more at the bottom of the container compared to ale yeasts. In a few weeks they will run out of food and settle to the bottom.

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Final beer update: Keg time. I take my time when it comes to fermenting lagers, since at a minimum I want them to ferment for around three weeks and then lager for a few weeks after that. Sometimes I lager in the keg while it carbonates if I'm in a hurry, and other times in the fermenter.

As I transfer to the keg I collect a bit of the beer to take a final gravity reading for my brewing notebook (which I've maintained since 2009) and for a taste. Flat, but good!

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