Star San and yeast starters

[Patterd Ale]

Whilst wrestling sticky dryish malt extract to make a starter for a whitelabs kolsch, I managed to hurl my Erlenmeyer flask across the kitchen. It did not survive. Thusly a trusty demijohn was called into use. Being unable to hit it with boiling water after sanitisation as usual, I applied starsan. For the first time ever I have no starter action. Unrelated or did starsan kill my yeast?
Any thoughts please?
Thanks all.

[Wonkydonkey]

I wouldn't have thought it would kill all, so there must be a few still alive, it may take a bit longer.
How long has it been going, shaking, or stirring ?
What was your method, ie, how much liquid (DME) did you use.

I'm sure the YW will come along, and tell you

[Patterd Ale]

I hope so, like you I would be surprised to have jobbed all of the cells. Its been about 4 days now, 1040 wort made from dme, shaken, not stirred. Always worked before.

[MTW]

Unless you dumped the yeast straight into a Star San ridden DJ, rather than put the DME wort in first and then add the yeast, I can't think it would be a problem.

Are you sure it hasn't fermented and you've missed it?

[Wonkydonkey]

That's what I was thinking, that's why I asked what was the method used. Not having a pic'y, it's a guessing game really.
Have you tried cold crashing it or tasting it. The latter is quicker.
The only other thing I can think of, was the DME was still to warm.

Best of luck

[IPA]

Whilst wrestling sticky dryish malt extract to make a starter for a whitelabs kolsch, I managed to hurl my Erlenmeyer flask across the kitchen. It did not survive. Thusly a trusty demijohn was called into use. Being unable to hit it with boiling water after sanitisation as usual, I applied starsan. For the first time ever I have no starter action. Unrelated or did starsan kill my yeast?
Any thoughts please?
Thanks all.

I have just had a similar experience with WLP 380. I did not use Starsan but it took 80 hours on the stir plate before it woke up. It has now turned into the best top working yeast that I have ever had. The head has the texture of yoghourt

[Patterd Ale]

It lives! It has finally started, incredibly slow start. Thanks all for the input.
That yeast of yours IPA sounds great!

[YeastWhisperer]

I will let you in on a dirty little secret. Star San belongs to a class of sanitizers known as acid-anionic sanitizers. Unlike bleach and iodophor, which are broad-spectrum halogen-based oxidizing antimicrobials, acid-anionic sanitizers are primarily bactericides that possess limited yeast and mold killing ability.

From page 180 of "Principals of Food Sanitation" (https://books.google.com/books?id=lCRxc ... age&q=acid anionic sanitizer limited yeast&f=false):

These sanitizers can be corrosive to unprotected metals and a skin irritant, inactivated by cationic surfactants, may foam too much for CIP equipment, are less effective at a higher pH, have limited and varied antimicrobial activity (including poor yeast and mold activity), and are more expensive than are the halogen sanitizers. The antimicrobial effect of acid anionics appears to be through reach of the surfactant, with postively charged bacteria by ionic attraction to penetrate cell walls and distrupt cellular function.

Phosphorphic acid is used to lower the sanitizing solution's pH in Star San. The surfactant used in Star San is dodecylbenzene sulfonic acid (see http://www.jstrack.org/brewing/msds/starsan.pdf).

Now, what charge do yeast cells hold? I will give you a hint. It is not positive.

I learned this lesson the hard way when I experienced a persistent low-level wild yeast infection after switching to Star San from bleach and iodophor. Star San is no longer my primary sanitizer. It has been relegated to secondary sanitizer status.

[YeastWhisperer]

Slow starts are usually signs that the culture had low viability and/or the medium was poorly aerated. A stir plate does poor job of aerating a culture. In fact, as I have mentioned before, stir plates were not designed for propagating yeast. They were designed for suspension cell culturing. Suspension cell culturing is a technique that is used to grow cells from multicellular eukaryotes (e.g., humans) in a laboratory setting. A stir plate keeps the cells from clumping together. Most brewing yeast strains are either non-flocculent or exhibit NewFlo flocculation. NewFlo strains do not flocculate until glucose, mannose, maltose, sucrose, and maltotriose have reached genetically set levels; therefore, they will remain in suspension with no assistance until these levels are reached.

The things that are important when propagating yeast are dissolved oxygen (O2), available carbon (sugar is carbon bound to water), and the minimization of stress. The stir bar in a stirred starter can be a source of cell wall shear stress. Pitching into a medium with too high of gravity can also stress yeast cells that have been in a quiescent state for an extend period of time. The preferred starter medium has a gravity that is 7.5 to 10% weight by volume (1.030 to 1.040), or 7.5 to 10 grams of DME per 100ml of solution.

[YeastFace Brew Co.]

I read somewhere that when Starsan breaks down it provides nutrients for yeast.

[Aleman]

It's basically phosphoric acid which provides phosphate. . . Yeast nutrient is ammonium phosphate and some people think that means starsan is a yeast nutrient. Unfortunately it is the the nitrogen supplied by the ammonium ion that is the nutrient when a wort or must is deficient in Free Amino Nitrogen (FAN).

Phosphate is a nutrient but wort is never deficient in phosphate.

I hate to do it again, but, unless someone can provide evidence to the contrary, that's another myth busted

[YeastWhisperer]

+1000

Aleman is on the money. Phosphate (PO4) is a salt that is formed via sequential dehydrogenation of phosphoric acid (H3PO4) . More than enough phosphate is provided by malted barley. Ammonium (NH4) is the nitrogen source in ammonium phosphate. Yeast is a single cell plant, and plants use nitrogen to form enzymes (which are proteins) and nucleic acids. While air is mostly nitrogen, plants cannot use free nitrogen (N2). Plants can absorb nitrogen in the form of ammonium and nitrate (NO3).


P.S. Moderators, does the software used for this forum support the [sub][/sub] and [sup][/sup] tags?

[YeastFace Brew Co.]

Thanks for clearing that up.

[Aleman]

P.S. Moderators, does the software used for this forum support the [sub][/sub] and [sup][/sup] tags?

Not as far as I am aware . . It is one of the few 'Failings' of phpBB3

[Patterd Ale]

Thanks for elaborating. Glad you guys have that depth of knowledge and pleased if I grasp half of it!