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chevelle383 · 04-05-2011, 06:02 PM

how is this not a sticky

**MalFet** · 04-05-2011, 08:37 PM

Quote:

Originally Posted by maxoldo

But isn’t it the same for a vial? If the ratio of vial mix is 50% yeast, 25% water and 25% glycerin, wouldn’t this be true to these proportions?
Just imagine a fermenter half-full of pure yeast, what chance of survival a tiny colony of nasty bacteria has?

The fact that StarSan isn't sufficient for freezing is relatively easy to demonstrate, and I'd encourage you to plate some samples if you're still not convinced. Without real sterilization, they get green and fuzzy fast.

The problem with your analogy (I suspect) is that yeast populations grow linearly with total volumes (2L of slurry has twice the cell count of 1L of equivalent slurry), but errant bacteria populations are more complicated because bacteria is typically growing on organic soils. A little blob of non-visible gunk might have a few hundred million bacteria in it, regardless of whether it's in a 20L carboy or in a 1mL microtube.

theredben · 04-05-2011, 08:51 PM

Quote:

Originally Posted by maxoldo

Just imagine a fermenter half-full of pure yeast, what chance of survival a tiny colony of nasty bacteria has?

100%. Every batch of beer made (aside from laboratory propgation) has bacteria in it. My beer has some, your beer has some, and the beer from every commercial brewery has some. The important part in brewing is keeping things sanitary (mostly free from bacteria) to ensure those bacteria do not build up enough numbers to affect the final product (no more than 1000 bacteria/mL from what I read). Remember that unpasteurized unfiltered beer usually has at least 1,000,000 yeast cells/mL

When you are propagating yeast from such a small number (anything less than 1 billion cells really) the problem is that you will also grow the bacteria/other contaminants to extreme levels, enough to affect the final beer. If steam pressure sterilization was not necessary then microbiologists the world over would not be spending megabucks and megatime on sterility. We go through the effort because it is needed. Period.

maxoldo · 04-06-2011, 09:10 PM

Now I’m convinced. Thank you all for input!

Is there a way to avoid buying a pressure cooker? Will a baby bottle sterilizer do(Philips AVENT Digital Steam Sterilizer)?
My SWMBO hates messy kitchen and since we already have that sterilizer sitting on the countertop she won’t mind me using it instead of buying another gadget for my new beer making hobby(read obsession)

**MalFet** · 04-06-2011, 10:50 PM

Quote:

Originally Posted by maxoldo

Now I’m convinced. Thank you all for input!

Is there a way to avoid buying a pressure cooker? Will a baby bottle sterilizer do(Philips AVENT Digital Steam Sterilizer)?
My SWMBO hates messy kitchen and since we already have that sterilizer sitting on the countertop she won’t mind me using it instead of buying another gadget for my new beer making hobby(read obsession)

In a word, no. Unpressurized steam just doesn't get hot enough before it blows away. Some people have experimented with a process called tindalization, but it is tedious and gets mixed reviews for efficacy.

ekjohns · 04-07-2011, 12:04 AM

try hitting up craigslist or consignment store. I found a brand new 19qt presto pressure cooker for $45. On my way to pick it up someone beat me 2 it. I should have asked for it to be help. Worst decission ever!

either way I have had one for a year now and just started cooking chicken in it. It is sooo fast and good. I cook chicken in 8 min and it cost me $0.80 per chicken quarter. More savings = more beer! W0oT

maxoldo · 04-07-2011, 06:58 PM

I'm getting a pressure cooker today!

I have washed some yeast from the last couple of batches, do I make starters first from those before freezing, to make sure yeast is active and healthy, or do I just collect yeast slurry and put it in vials with glycerin/water solution? Also, how can I check it’s not contaminated, do I just smell and taste the starter?

**MalFet** · 04-07-2011, 07:20 PM

Quote:

Originally Posted by maxoldo

I'm getting a pressure cooker today!

I have washed some yeast from the last couple of batches, do I make starters first from those before freezing, to make sure yeast is active and healthy, or do I just collect yeast slurry and put it in vials with glycerin/water solution? Also, how can I check it’s not contaminated, do I just smell and taste the starter?

Make a starter. If you are planning to freeze for any significant period of time, it'll be good to have healthy yeast going in.

Contamination can be tough to test, but tasting your starter steps for perceived changes is a good bet. Beyond that, you'd have to plate out individual colonies.

**DBbrewing** · 04-11-2011, 12:25 AM

I used my 1st batch of frozen yeast this weekend and it took off in 5 hours so my 2 carboys of Apricot Ale are fermenting like crazy.

bojacked · 04-22-2011, 01:03 AM

Hey sorry if it's been addressed I read pages 1-25 on the thread earlier and searched a bit. My question is this. I filled my jars to wash yeast with tap water and capped them in ball jars then boiled them. Will this water kill my yeast if I wash with it? My tap ph is 8ish and I don't have a way to test further for chlorine/ chloramine in my tap water. I've been RDWHAHB and I don't want to kill this awesome cake. Will my sanitized tap water kill the pacman yeast I've got a nice cake of? Thanks. B