
1. MASHING IN
Brew days start at about 8 am, by first grinding in the malt. We dump the malt into the auger, which feeds it to the mill. The mill setting is very important. We grind the base malts find enough to yield the maximum extract without dissolving the harsh tannins in the malt. We also have to be careful not to destroy the kernel hulls. Different malts and wheat are ground at different settings.
2. LAUTERING
The mash/lauter tun has a metal screen in the bottom of it. This screen is fine enough to keep the grain from passing through. When conversion is complete, we begin what is know as the vorlauf, a German term referring to recirculation of the unfermented liquid, known as wort (another German term). We pump the liquid back over the grain bed in the mash/lauter tun until the fibrous material in the grain bed (the kernel hulls) is compacted enough to form a filter. This natural filter allows the extract, or wort, to “run off” clear. This process takes about 15 minutes.
Then, we run the clear wort off into the kettle through a very small tank known as the grant. The grant serves as a staging vessel to allow for the consistent accumulation of wort and to monitor its clarity and density. The grant acts as a buffer-zone to prevent the wort from flowing so quickly it over compresses the grain bed. If the grain bed becomes too tight, the rate of run-off will slow, or stop completely. It requires about 1.5 to 2 hours to fill the kettle. During which time, the density of the wort (its gravity) or the concentrations of sugar present is monitored to ensure the proper gravity when the kettle is full. Once the kettle is full, we push the spent grains out into a tip dumpster. From there, they are dumped into a farmer’s trailer and they use the spent grain as filler feed for his livestock.
3. BOILING
When the kettle is full, the wort is brought to a boil. We boil the wort for a full hour to an hour and a half depending on the brew. At the beginning of the boil, we add hops high in bitterness because it takes longer to extract the bitterness. Later in the boil, we add other hop varieties that are more aromatic. The aroma boils off quickly, so we do not want to add them too soon. The boiling also sterilizes the wort and breaks down large proteins. The boil also evaporates sulfur compounds, which are not conducive to good beer.
After the boil is complete, the wort is “whirl-pooled” in the kettle. The protein compounds coagulate to form a substance no one wants in their beer so we pump the wort out of the bottom of the kettle. It then goes back in through a tangential valve back into the kettle, causing it to spin. The centrifugal force piles the solids now present in the wort at the bottom of the kettle in a neat pile.
4. COOLING
The wort is now drawn off the bottom of the kettle and pumped through the heat exchanger. This cools the wort by passing over many stainless steel plates with cold water and chilled antifreeze on the other side. We cool our wort to 55 – 75 degrees Fahrenheit depending on the type of yeast we use. Lager yeast ferments at the colder temperatures while ale yeast strains ferment much warmer. We also add oxygen, as yeast cells require it to grow and multiply. The wort, with yeast and oxygen, is pumped into a fermenting tank in our cellar. Here primary fermentation takes place. It remains here for 5-10 days depending on the yeast strain.
Bottling
The average bottling day will start Tuesday morning around 8 A.M. and will finish around 3 P.M.
Our new Kosme filler was put in at the beginning of April in 2014.The Kosme replaced our stone aged Muyers filler that was put in the building in 1985 when the brewery opened up. It was also replaced because the old one was built in the late 50’s, not a bad run I’d say. The new 24 head filler can push out 120 bottles a minute, but and there is a but, we only run on average 88 per minute. So, that means we can do 180 cases per hour. This is the reason why we do the slower speed.
Every Tuesday ,four of us will bottle on average seven hours. One person will run the machine, another will put the empty bottles on the line, another will grab four filled bottles at a time and put them in the packaging and the last person will grab them after the packaging goes through the taper and stacks them to order. So it starts to get pretty tiring doing all that by hand over seven hours.
Kegging
Cleaning kegs on Thursday to fill them on Wednesday so send them out on Thursday again.
Before a keg is ever filled even if its brand new we will clean it. The keg cleaning process really isn’t a difficult job, but it does take time. Our keg cleaner can do 3 kegs at a time, which is 1 more then our previous cleaner. There are about 5 cycles to cleaning a keg, the first being to blow out all the old product. Next the it will spray the inside with a water/pbw combo, then rinse that out and do another cycle with a water/acid mix, once again rinsing it out once its done. The last 2 cycles include blowing air in just to make sure everything gets removed, then its pressurized with C02. The whole process can take up to 8 minutes.
After the cleaning process it is taken to our ramp so the person filling (aka: Tom) knows which kegs are clean so he can fill them. Filling kegs like cleaning them isn’t all that hard, but it also takes time. Taking the empty kegs Tom puts them by the tank that has the beer he will be filling the kegs with and sets all his lines up to fill the kegs. Hooking up the tank straight to the kegs Tom can fill 2 at a time averaging 2 every 5 minutes. After they are filled he puts a cap and collar on so we can tell which is which. Once they are filled 2 or 3 of us will hall the kegs up the ramp and on to palates for orders. (Rain, Snow or Shine)
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