StarSan and the health of yeast

Discussion in 'Beginners Brewing Forum' started by Scott Butler, Nov 15, 2018.

  1. Scott Butler

    Scott Butler New Member

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    Going to harvest yeast off my next brew. It may only be $8.99 for the yeast, but if I can reuse it six or ten times....well that just paid for a few grain bills.

    So, that said....

    Sanitizing....how does StarSan not effect the health of my yeastie friends?
    Or does it, and just by the huge numbers harvested that they survive?

    How long can my harvested friends be kept before another brew is made?
    And finally, is anyone using the scientific speality flask(sort of looks like a conical fermenter, but it's 1000ml and made out of glass)?



    Thanks
    Scott
     
  2. Hawkbox

    Hawkbox Well-Known Member

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    What do you mean about starsan? What are you planning to use it for?

    I do lots of yeast harvesting and I starsan the vessel before using it.

    I have reused yeast that was 6 months old without issue, I generally do a starter though and harvest from the starter for the next batch so I recharge the yeast.

    Do you mean an Erlenmeyer flask? If so get at least a 2000ml one, a 1000ml one won't be big enough.
     
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  3. soccerdad

    soccerdad Active Member

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    I have always heard that the acid in SS acts as something of a yeast nutrient .. I honestly don't know the source for that .. except my friend Butch
     
  4. Nosybear

    Nosybear Well-Known Member

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    Star-san is essentially phosphoric acid and a surfactant - the foaming part. It's used at a fairly low concentration - 1 ounce to 5 gallons, or 1:640 concentration, so the mixed sanitizer you're using is mostly water. So there's a very tiny quantity of its ingredients left behind. If you're concerned and have a pH meter, try measuring the pH of water you're adding to a carboy. Sanitize it as usual, then add the water back and mix. Measure the pH again and see what change you have. There won't be much, if any at all. That's the effect on your yeast.
     
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  5. thunderwagn

    thunderwagn Well-Known Member

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    I don't know if that's homebrewing folklore or true, but I've heard the same. I do know I've never feared the foam when it comes to harvesting and saving yeast and sanitizing with Star San.
     
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  6. Nosybear

    Nosybear Well-Known Member

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    It provides a bit of phosphate and all living things need it. But that's not a primary function and there's enough phosphate in the wort to satisfy the yeast, as long as you're reasonable with adjuncts.
     
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  7. SDB777

    SDB777 New Member

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    So when I use StarSan, I will not kill one single cell of yeast that is harvested in the container that I sprayed with the solution?

    Then how does that explain this?



    I currently just boil the containers(mason jars) for ten minutes, harvest yeast into the jars and wash as necessary(using more of the boil mason jars). I spray the StarSan onto the lids and 'rings' and generally my hands are dripping with the stuff too.... I haven't been needing the same yeast yet(collected three different types), but I am hoping it'll still be good.



    HAWKBOX, thanks for the head's up on the 2000ml size....that'll save me some future headaches.



    Thanks again
    Scott
     
  8. Nosybear

    Nosybear Well-Known Member

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    Hang around the Internet long enough and you'll find someone that insists the earth is flat. And will provide scientificly sounding evidence to prove it. If you're interested in the death of one single cell, you're concentrating on the wrong thing. I don't see anything wrong with your process but be aware: Screwing the mason jar lids on will likely kill thousands, if not millions of yeast cells by crushing them.... ;-)

    It should last a week or two, after that, you'll need a starter.
     
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  9. Hogarthe

    Hogarthe Well-Known Member

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    If you are using star san or any other liquid sanitizer as long as you drain the container before putting the yeast into it there won't be enough sanitizer left to kill many yeast cells. By the time all the yeast slurry is in there it will dilute the sanitizer so much it will be ineffective.
     
  10. Hawkbox

    Hawkbox Well-Known Member

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    You'll probably kill a bunch of cells, that's why you fill the jar with way more than you need.

    This is all eyeballing unless you buy some really fancy gear. I also like my 5000ML Erlenmeyer but I've started doing 10 gallon batches and it makes things easier.
     
  11. Trialben

    Trialben Well-Known Member

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    I've also heard of brewers acid washing their saved yeast with phosphoric acid I've not tried this myself but I see the thinking behind it meaning the acid will/should kill foreign microbes but wont harm the brewers yeast. Just to throw another 2c in the fermenter :rolleyes:
     

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