Yeast Nutrient

[felten]

Perhaps now I'll have a chance to use up my 280g tin of lowan bakers yeast ^_^

 

[Mikedub]

A correction on those numbers. Teaches me for posting from memory.

Using 4g dried yeast per L, an all-sugar brew will happily munch through 50 gravity points before it starts to slow down. Now, less nutrient is needed for beer, for two reasons. One is that beers only ever attenuate about 75%, and the second is that the malt at worst generally provides about 67% of the amino nutrients. So that works out to a requirement of 1g/L supplement.

100g dried yeast occupies 2/3 cup or 9 Tsp. An average-strength brew of 1050, for a standard volume of 22.5L, requires 22.5g dried yeast or about 2 Tsp supplement. That is about three packets of unwanted kit yeast. Add 50% for strong Belgians, extra stouts, old ales and the like. Double that quantity for barley wines. Note that the yeast precipitates rapidly, which is a good reason not to add it to any wort that will subsequently be racked (like off the boiler trub). Contrary to rumour, it doesn't add a vegemite note. Any yeast that looks granular is still alive and needs to be boiled, whereas pulverised stuff like torula yeast doesn't.

I missed adding yeast nutrient to the wort boil, so last night I boiled up 2 old yeast packets in 300mil water for 20 mins and transferred to a sterile jar, as mentioned elsewhere in this thread, it smells friggen awful,

can I hydrate a pack of us05 straight into this jar before pitching the lot together ya reckon?

 

[muckanic]

can I hydrate a pack of us05 straight into this jar before pitching the lot together ya reckon?

The problem is that that's not really hydration. The live yeast will sense that it is in a highly concentrated nutrient environment, and that could confuse it regarding the various substances that it needs to start manufacturing.

 

[Mikedub]

makes sense, cheers

btw, when boiling up the two 7g packets I'm pretty sure I could hear the tiny screams of 280 billion yeasties,

 

[Bats]

I have heaps of dried yeast packets that are no good for fermenting.

I am currently brewing a 20L ESB. Should I only put 1 packet in @15 or so or will 2 packets be better?

Is too much old yeast as nutrient detrimental?

 

[Glot]

Would throwing a swiss zinc tablet into the fermenter do any good? They seem to contain most of what yeast needs. If thrown into the boil, a lot of the B vitamins would be lost from heat. Have also read that half a teaspoon of vegemite is also a help if nothing else available. I am guessing you don't put it on toast first. Anyone have any comments on these two?