More yeast growing questions

[StevieDS]

Ok so Ive grown some US-05 yeast from a bottle of brew I made a few months ago.

I did it as follows:
Added about 50ml of 1.020 wort, left for 3 days
Added 200ml of 1.020 wort, left for 3 days
Added 1L of 1.020 wort yesterday and its now bubbling away nicely.

My question is, will it be ok to add this directly into a 27L batch Im making on Saturday with an expected OG of around 1.060? That'll be 3 days since I added the 1L mentioned above.
I know I probably stepped up the amounts a bit too quickly (Ive never been too patient), but its fermenting away as I type. Will it be ok to go into the brew or should I step up again first?

 

[Good Ed]

I don't think you will have time to step it up again before Saturday, so I would go with what you have got, even though this will probably be a bit short on quantity. You should also put it somewhere cool when finished to let the yeast settle out, and then decant the spent wort off before pitching. When you have decanted off the spent wort on brewday you can then add some cooled wort from half way through your boil to get the yeast active ready for pitching.

Next time use wort of 1030-1040, use 100g DME for every 1L of water, and also give yourself a bit more time to get your yeast ready.

Good luck with the brew :

 

[Yob]

You really should be aerating the starter, to be honest I wouldnt be using that lot, check out http://www.mrmalty.com/calc/calc.html for both starters and slurry pitching rates/tools, I used this quite a lot until I worked out the patterns. (I use the compact yeast slider all the way to thick slurry as I let it all settle in the fridge)

If Ive collected a slurry, and I usually collect 100ml of compacted, rinsed yeast, I know that if within 2 weeks I will need ~60ml - 70ml for a 1060 wort, if Mr Malty suggests that my viability has dropped too far (over a month) then I will use a portion of the slurry and make a starter, I always use a stir plate though so I know that the yeast I grow has optimal health.

Hope this hepls a little.

 

[StevieDS]

You really should be aerating the starter, to be honest I wouldnt be using that lot, check out http://www.mrmalty.com/calc/calc.html for both starters and slurry pitching rates/tools, I used this quite a lot until I worked out the patterns. (I use the compact yeast slider all the way to thick slurry as I let it all settle in the fridge)

Sorry I'm not sure what ur saying, are u saying I shouldn't use it?

 

[Good Ed]

I'm also not sure what Yob is saying, but you'll be fine with what you've got for tomorrows brew

 

[StevieDS]

Cool, I got a pack of us-05 today anyway so im gonna split the brew, 13 litres with my reclaimed yeast, 13 with the new.
I think it'll give it a better chance of working, and it'll be interesting to see the difference. Also I don't have the confidence to risk a full batch of beer for the sake of 3 quid.

 

[Devonhomebrew]

I use a yeast medium which has nutrient and sugar in it the brix is 25 so thats a wopping 1.100 on the hydrometer. We use 1 shot of it at work to wake up yeast but at the same time i use the medium to grow yeast in my lab when watered down to 1.030

 

[steve963]

I saved some US-05, and the resultant beer is tainted. not sure if its my cleansing etc, but be careful :whistle:

 

[Yob]

You really should be aerating the starter, to be honest I wouldnt be using that lot, check out http://www.mrmalty.com/calc/calc.html for both starters and slurry pitching rates/tools, I used this quite a lot until I worked out the patterns. (I use the compact yeast slider all the way to thick slurry as I let it all settle in the fridge)

Sorry I'm not sure what ur saying, are u saying I shouldn't use it?

If you have made a starter, this implies you started with a small amount you wished to grow, an un-aerated starter will not produce a healthy (as healthy) stock of yeast due to the anaerobic conditions. (Aerobic fermentation is where they grow, anaerobic is where they switch to fermentation)

When growing yeast up they need aeration to be at optimal health, as I understand it when yeast "bud" they require o2 to maintain optimal health... simply throwing them in a bit of wort isnt enough to maintain this optimal health, will it work? more than likely, will they be as happy as they would otherwise be? Will they have optimal Glycogen and trehalose reserves? Im not so sure.

I personally, have a starter on the stirplate (even manual shaking the bottle every few hours is better than nothing) for 2 days, I then let it sit for another 2 days for them to build up their "fats" and then good to go. Each of the processes allows the yeast to do different functions according to the conditions theyre in.

Cheers