This Week in BrewZasters: Go Yeast Old Man

Yeast Explosion

Yeast will build up some explosive pressure when they are well fed in a sealed container. I am still finding spots of yeast in nooks and tiny crevices around the kitchen.

Microscopic yeast are in the air all around us. They are the reason that we have beer, wine, and other alcoholic drinks.

Beer (and therefore yeast) lubricated the rise of civilization:

At some point in prehistory yeast fell into the gruel of one of our ancestors–after all, yeast is in the air around us. The gruel had been made from grain that had started to sprout (when seeds sprout an enzyme is released that breaks the starches stored in the seed into sugars the seedling will need for energy). Or perhaps the gruel tasted bad and our ancestor spit into the bowl (our saliva contains enzymes that break starch into sugars). The yeast started eating the available sugars. As they ate they produced ethanol (C2H5OH) and carbon dioxide (CO2). The next day, our ancestor would have noticed some froth on the top of the gruel, sipped it, and she (yes, she) found it didn’t cause problems. In fact, she felt better after drinking the frothy liquid.

She had discovered what Oscar Wilde discovered generations later:

“I have made an important discovery…that alcohol, taken in sufficient quantities, produces all the effects of intoxication.” — Oscar Wilde

Without yeast we would not have beer or civilization.

A couple of weeks ago my friend Ron (who runs Kelsey Creek Brewing) gave me a container of Irish ale yeast–a big container of yeast. So much yeast that I could have used it for 100 gallons of wort (rather than the 5 gallons I planned to make). I put the plastic container in the refrigerator for use in the following day’s brewing. Cold temperatures make yeast less active. But, even with the cold, they were active enough to produce a lot of CO2 gas.

The picture above shows the aftermath of my opening the plastic jar. I’m still finding yeast in places in our kitchen.

Fortunately for me, my wife loves the beer I make.

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Here is some yeast (in a Better Bottle fermenter) eating sugars and producing CO2 and alcohol:

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Kelsey Creek Brewing opens its doors

Kelsey Creek Brewing Company opened its doors to the public for the first time on Saturday, July 14, 2012. Publican Ron Chips had a smile wider than Main Street in Kelseyville where Lake County’s newest public house is located. “It’s been a constant stream of folks since we opened the doors,” Chips said.

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Ron Chips started as a home brewer and quickly turned pro by attending brewing school and interning at Lagunitas in Petaluma. The brewing company has been in the works for almost a year.

On tap for the opening was Kelsey Creek pale ale an American Pale Ale that was brewed with Ivanhoe hops grown in Clearlake as well, and No’na’me Irish Red ale.

Chips showcased one of the centerpieces of the brewery: a Russian made dispenser for filling half-gallon to-go bottles known as growlers. “The growler filler first flushes the bottle with CO2 to remove all oxygen, which is the enemy of fresh beer,” Chips said. “Then it fills the growler slowly so it does not foam. Last, there is a layer of Co2 at the very top. Most growlers can last only a few days without being opened, but mine can last for a month, making the beer fresher for a much longer of time,” he said, “I knew Kelsey Creek Brewery had to have it as soon as I saw it at a trade show.”

The brewery has an outdoor seating area (a beer garden), a long copper bar, and even purse hooks beneath the bar for women to hang their purses while they perch.

Kelsey Creek Brewing’s address is 3945 Main St., Kelseyville, CA 95451, telephone number 707 245-8402, and is open Wednesdays through Saturdays from noon to 8:00 p.m. and Sundays from noon until 5 or 6:00 p.m.

Update (7/21/12): Kelsey Creek Brewing has had to open on Mondays and Tuesdays due to the pent up demand for good and fresh beer in South Lake County. And, Ron now has a third ale on tap: a Scotch ale.

Yeast Ranching notes

These are some notes I took when the owner/brewer of the soon-to-be-opened Kelsey Creek Brewing gave a seminar on yeast ranching to some members of the Lake County Homebrewers club.

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To grow and cultivate (aka “ranch”) yeast you want clean clear wort with the trub precipitated out to mix with agar to put on the petri dishes. You will also need inoculation loops and  inoculation needles.

Required for yeast ranching:

Process:

Sprinkle agar over the top of the cooled wort. Do not dump the agar rather sprinkle in around (7g/250ml). No need to stir. Sanitation is not critical yet, since it will go into a pressure cooker which serves as an autoclave. Be sure to add nutrient to your wort.
After it has been used, every time you touch something in the pressure cooker you spray it with isopropyl 70 alcohol.

Pour the agar & wort solution using the “pacman” technique
Make sure the agar sets up ~45min before flipping over to lessen the condensation

Place a drop of diluted yeast solution on the dish with the agar. Then remember the spot and drop sterile saline on the yeast’s spot.

Then use the needle to drag the drop to streak it.

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Nice to haves:

  • Hemocytometer (local veterinary offices may have these lying around)
  • microscope

To check yeast viability a bulb flask is used (9 ml of sterile and 1 ml of yeast and 1 drop of methylene blue) and .0001 ml of of solution is placed on hemocytometer slide

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