Yeast Starter SG

[aolcot]

Hi All,

I've been making starters now for the last few brews and they really do seem to make a great difference. Fermentation is flying a few hours after pitching and they finish well. The DIY stir plate on this forum is just awesome and works great. I generally use liquid yeasts.

My question though is regarding what gravity to make the starter wort? I've been making 1.036 just because that's what beersmith defaults to, even though my beers are generally higher 1.050+ often. My next brew will have an OG of about 1.095 which got me wondering if my yeast starter wort should be higher to match or if it doesn't really matter and 1.036 is going to be just fine..

What are peoples thoughts? do they generally make the same wort SG for all beers or adjust it based on the OG of the beer the starter will be pitched into?

Thanks in advance
Arthur

 

[Martybhoy]

I also use 1.036, but the volume of water and amount of DME increases as expected OG increases. The 1.036 doesn't have anything to do with your wort's OG.

Beersmith will give you a target number of cells based on expected OG, and volume of wort. Adjust your starter size until your resulting yeast cells match your target number

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[aolcot]

I also use 1.036, but the volume of water and amount of DME increases as expected OG increases. The 1.036 doesn't have anything to do with your wort's OG.

Beersmith will give you a target number of cells based on expected OG, and volume of wort. Adjust your starter size until your resulting yeast cells match your target number

Sent from my MotoG3 using Tapatalk

Thanks, I think the penny has just dropped and makes sense now.. It is all about hitting the number of yeast cells for the recipe rather than the wort's OG...

So, purely just out of interest, are there any scenarios where you would want to make a starter with a higher SG than 1.036? would certain yeasts want more, or maybe wine yeasts....

 

[Martybhoy]

Not that I am aware of. In Beersmith, changing the gravity of the wort from 1.036 to any other number, doesn't change the resulting number of cells from the starter.

At a guess, I'd say lower than 1.036 might not have enough food for the yeast to grow. Too high and there might be too much, and the won't be worked enough. Guides seem to lie between 1.030 and 1.040.

I stick to 10% DME (weight) of volume of water for my starters and have had success each time.

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[MyQul]

Thanks, I think the penny has just dropped and makes sense now.. It is all about hitting the number of yeast cells for the recipe rather than the wort's OG...

So, purely just out of interest, are there any scenarios where you would want to make a starter with a higher SG than 1.036? would certain yeasts want more, or maybe wine yeasts....

As martyboy says between 1.030 - 1.040 is good for a starter. I generally make mine about 1.038/1.040. I cant think of a situation where you might need to make a stronger starter. In fact it wouldn't be a good idea as a stronger starter would stress the yeast and may produce off flavours in the final beer.

JFYI there is a situation where you may want to make a weaker starter at about 1.020, and that is when you culturing up yeast from a bottle conditioned beer. This is because the initial cells that you harvest will be tired, old and stress (kind of like me). So doing a weak starter for the first couple of step ups gives the yeast a chance to build up the cell count and health without further stressing it

 

[aolcot]

Thanks for the responses chaps :thumb: really helps and useful info regarding weaker starters.. thanks again :smile: