fermentation and yeast?

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zamboniroadkill
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fermentation and yeast?

Post by zamboniroadkill »

Put down a robust porter, pitched with white - ale yeast and nothing happened for over almost 4 days I thought I had a disaster and was just getting ready to test, figuring I had left to much sanitizer, boiled improperly or perhaps had some bad yeast and the thing goes nuts and blows off the airlock.

anybody have an idea why nothing for so long and then such a sudden strong fermentation?

thx

iceman
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slothrob
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underpitch

Post by slothrob »

It sounds like the yeast was sickly, you underpitched, it took a few days to grow up to a proper number, then started actively fermenting. You should look into using a starter.
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zamboniroadkill
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THX

Post by zamboniroadkill »

That makes sense am fairly new to this and just never had it happen. Will make a starter or pitch 2 vials next time. any way to know how much yeast is needed on any given batch? or should I just always make a starter

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yeast pitch

Post by slothrob »

Mrmalty.com has a great pitching calculator. It's probably going to calculate more yeast than most homebrewers usually pitch, but most brewers would probably make better beer if they used the right amount of healthy yeast.

I think the manufacturers say that 1 vial should be good for 5 gallons at as much as 1.070, but the numbers are probably more appropriate for a small beer like an Ordinary Bitter or a half volume batch. I often make a small beer with a new vial, then pitch a portion of the yeast cake for a larger beer after that.

The other issue is when the yeast isn't in the best shape, maybe it's getting a little old or wasn't handled that well. That's the reason that a lot of brewers, who aren't willing to risk a batch, make a starter for every beer.

A simple starter that will give you fresh yeast and bump up your cell number is really quite easy. All you need is a sanitizable bottle, like a half gallon or 1 gallon juice or wine jug, make 1-3 qts. of a 1.035-1.040 wort, and add it to the bottle with the yeast, covering it with some sanitized foil. The best option is to ferment the starter out someplace warm over a day or two, then refrigerate it overnight (5 hours or so can be enough) to drop the yeast. You can store that in the fridge up to a week or 2 and then pour off the liquid and add the yeast to your beer.

Alternately, you can make a quart or two starter as little as the night before and add the entire active starter to your wort. This should give you nearly as many cells and an actively fermenting population, but you will be diluting your beer a little with the starter wort.

You'll probably see starts in as little as a few hours using those methods.
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