one or two packs?

[lukasfab]

hi all

should i be pitching one or two packs of US05 into 20l of 1.068?

cheers

 

[sp0rk]

1 if you're rehydrating

 

[peas_and_corn]

/thread

 

[Lemon]

Use both.
There is an extremely long answer which shows how even two is insufficient using industry, and home brew, calculations, some one will mention mr malty, and the up shot is.

Use both

Lemon

 

[Yob]

Anything over about 1050, 2 packs or a starter if using liquids

 

[lukasfab]

cheers fellas

 

[hoppy2B]

Yeast is said to double every 12 hours so one must wonder if its worthwhile pitching 2 packets.

If cost isn't a factor why not just pitch 4 packets and save yourself a whole day.

 

[wereprawn]

Would only continue to reproduce while there was available oxygen wouldn't it Hoppy.

 

[hoppy2B]

Would only continue to reproduce while there was available oxygen wouldn't it Hoppy.

Third paragraph down.

http://www.maltosefalcons.com/tech/yeast-propagation-and-maintenance-principles-and-practices

 

[Yob]

Yeast is said to double every 12 hours so one must wonder if its worthwhile pitching 2 packets.

If cost isn't a factor why not just pitch 4 packets and save yourself a whole day.

Third paragraph down.

http://www.maltosefalcons.com/tech/yeast-propagation-and-maintenance-principles-and-practices

Third paragraph

Yeast is a facultative anaerobe which is just a fancy way of saying that it can survive and grow in the presence (aerobic) or absence (anaerobic) of oxygen. The presence of oxygen determines the metabolic fate of the cell. In terms of the yeast cell, its survival, growth and metabolism is optimal in the presence of oxygen. In this case, yeast will rapidly grow to high densities and will convert sugar (glucose) to carbon dioxide and water. Under anaerobic conditions, yeast grows much more slowly and to lower densities and glucose is incompletely metabolized to ethanol and carbon dioxide. It is important to realize that optimal yeast growth is distinct from fermentation. Therefore, the conditions and methodologies used for propagating and maintaining yeast need not be identical to those used for fermenting wort. The purpose of a yeast starter is not to produce an enjoyable fermented beverage but rather to produce a sufficient quantity of yeast for subsequent fermentation. Propagation conditions should be such that a maximal amount of yeast is produced which provides optimal fermentation performance once pitched. What do we mean by fermentation performance? The main criteria for fermentation performance is based on the rate and extent of fermentation as well as the production of a beer with a balanced sensory profile with no off-flavors/aromas or inappropriate esters.

2 word Hoppy

Pitch Rate

many of the things you do to yeast are formed from opinion and not backed by any distinct research, especially starters and correct pitching rates.. just coz it eventually finishes does not mean it was therefore correct and could not have been better and/or cleaner at the end.

Its my understanding that anaerobic growth is nowhere near as good for the yeast cell as aerobic growth and inhibits their ability to repair resulting in weaker yeast, extrapolated a few brews and youre in trouble..

 

[jyo]

Anything over about 1050, 2 packs or a starter if using liquids

Always. Best chance of a clean ferment (not mentioning temperature control).

 

[hoppy2B]

Yes Yob, it does state in that article that even subsequent batches repitched and well cared for can still lack performance.

 

[danestead]

rather than listen to opposing views and links to artices how about you split the batch into 2 fermenters. Pitch 1 pack into one of the fermenters and half a pack into the other. Taste, and decide what pitch rate you prefer.

 

[hoppy2B]

Actually, I notice that article says yeast will double every 2-3 hours.

I tend to make a starter, even with dry yeast, and have been ever since I started beer making. Pitch rate isn't really an issue for me.

 

[Judanero]

many of the things you do to yeast are formed from opinion and not backed by any distinct research, especially starters and correct pitching rates.. just coz it eventually finishes does not mean it was therefore correct and could not have been better and/or cleaner at the end.

^ Agree with this.

I tend to make a starter, even with dry yeast, and have been ever since I started beer making. Pitch rate isn't really an issue for me.

If you're happy with the beer you make that's all that matters mate, that being said some of the yeast advice I've seen you give is questionable at best.

 

[danestead]

Read the yeast book by zamil. All answers are in there. I have ready it twice and still dont understand the lot. Yeast are a very complicated thing and you will produce different esters, phenols, off flavour etc based on your pitch rate and health.

 

[Judanero]

I was going to recommend that exact book. Comprehensive, reasonably straight forward, and most of all explains the 'why' of all things yeast.

An invaluable resource for anyone looking to improve their fermentations.

 

[Burt de Ernie]

How many packs for this??

 

[Judanero]

Eleventeen.

 

[hoppy2B]

^ Agree with this.



If you're happy with the beer you make that's all that matters mate, that being said some of the yeast advice I've seen you give is questionable at best.

What the hell is your problem? Mind your own business and give people whatever advice you wish and stop your trolling and criticism. I am fed up with the crap from the likes of Yob and yourself.