Homebrewed Yeast Extract

Two most common components of almost every agar are some kind of hydrolyzed meat or vegetal protein and yeast extract. Today we’re going to look at possibility of making yeast extract at home.

After bottling the Troubadour (Raspberry aged Berliner Weisse) I had 3-4 liters of yeast, bacterial, and raspberry sediment left in the carboy and decided to try and make yeast extract out of that. I collected about 2L and thought about how to break the cells open. The sediment (in parts) was first placed into a blender and blended on highest speed for several minutes with additions of the meat tenderizer. This served two purposes – the shearing force to physically break the cells open and release their contents into the solution as well as to make the solution hypertonic, as meat tenderizer has a hefty amount of salt in it, to help the surviving cells die and provide addition protease to chew up the released peptides. After that, some RO water was added to make it around 3L and it was left until the following evening near the heater. After maybe 5-10 minutes it started looking like cell lysate, for those of you familiar with such things. The following evening I put it all into a pot, boiled for a few minutes, let cool until the morning, and transfer into flasks. This “soup” was then filtered through a cloth and 4 layers of paper towel. No matter how much I tried to get it to be clear, I could not and started thinking that most likely I can’t do it, at least not at home. Just to take it one step further I decided to take some of it to the lab and centrifuge. After spinning at 5000rpm for 10 minutes, there was some sediment and the resulting supernatant was still cloudy. When 1-2 mL of it is taken, it is crystal clear, but collectively it is not, which makes sense if there is a lot of protein there. The taste is horrible, but then what do you expect? All of it was pressure-cooked and is sitting on the shelf. It is quite acidic and I’ll bump the pH up to around neutral with some NaOH before using. Most likely I’ll use it in my next batch of plates at something around 1:10-1:50 vol.

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K-Rye Me a River Pale Ale

Since I started posting about my brewing adventures rather than just yeast with the previous Winter Gruit post, I figured I would continue doing that. Today we come back to my last Pale Ale. Again thanks to Valley Malt MotM there was a bunch of malts on hand and I threw some stuff together. Recently I’ve been taking a rather unscientific approach in my brews – I don’t bother measuring OG, FG, adding finings and so on. Maybe it’s just me being lazy due to perpetual business or it could just be that I’m brewing it for my own drinking pleasure and don’t really care to know everything about it. In either case, the following stats are what I was aiming for. Note the use of juniper 🙂 I guess when winter is here I just can’t get enough of it!

K-Rye Me a River
Date Brewed: 16 Dec 2011

Wort Volume Before Boil: 6.25 US gals
Wort Volume After Boil: 5.25 US gals
Pre-Boil Gravity: 1.044 SG
OG: 1.056 SG
FG: 1.013 SG
ABV: 5.6 %
IBU: 136.4 IBU
Color: 8.4 SRM
Fermentation Temp: 67 degF

Fermentables
Valley Pilsen Malt 5.00 lb
Valley Rye Malt 5.00 lb
Valley Light Crystal 1.00 lb

Hops
US Summit – (18.2 %) – 1.00 oz – 60 Min From End
US Chinook – (11.0%) – 1.00 oz – 15 Min From End
US Columbus – (14.5%) – 1.00 oz – 15 Min From End
US Chinook – (11.0%)  – 1.00 oz – 5 Min From End
US Columbus – (14.5%) – 1.00 oz – 5 Min From End
US Chinook – (11.0%) – 1.00 oz – Dry Hop In Keg

Other Ingredients
Juniper Berries – 10g – 15 Min From End

Yeast
US-05 SafAle

Single Step Infusion (68C/154F)

Poured everything into the fermentor, including hops, juniper berries and hot break.

Picture taken several minutes after pour and the head started to recede.

Appearance: Pours very cloudy and reddish orange in color. 3 fingers of thick, incredibly thick, ice-cream-like head made of tiny bubbles that lasts for ever. Bubbles slowly crawling from bottom up indicating that this beer is thick. Great lacing. I cold conditioned it in the keg for a month and it didn’t clear up one bit over that time. Still as cloudy as it was on the first day.

Smell: Aggressive C-hop aroma. Very strong pungent and piny notes.

Taste: Hops hit your tongue like a hammer on anvil almost making it roll up, shrivel, and apply for political asylum. Once the initial bitterness shock goes away, a wave of strong hop flavor rolls over. Massive piny and grassy flavors dominate the scene with earthiness and woodenness playing in the background. Then sweet malt begins to shine through with spicy rye taking the lead. Long, chewy, malty and bitter finish.

Mouthfeel: Full, thick, almost oily. Totally awesome. Medium carbonation keeps it from being syrupy in consistency.

Overall: This is not a quaffing ale. This is something you pour yourself a pint of when you come home in the evening and sip on over the course of dinner. Very rich, thick and hoppy without high alcohol knocking you out. Rye makes it possible to brew really rich mid-abv brews and this is a good example of this. I’d say this is a nice winter Pale Ale. Drinking it makes me think of snow and evergreens. If it gets brewed again, I’ll cut the hops to around 90 IBU to make it a bit less aggressive. I’m not concerned over its persistent cloudiness and even like it that way because it fits even more into the “snow and pines” theme that everything about it brings to mind.