# Diammonium Phosphate



## deebee (11/8/04)

I bought a pack of yeast nutrient on the weekend - diammonium phosphate - but I am not sure how to use it.

1. Do I just chuck some into the boil a few minutes out from the end?
2. Do I use it only in the starter or is it useful in the brew itself?
3. Anything else?


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## Hoops (11/8/04)

The yeast packets used for distilling have heaps of diammonium phosphate in them and they are added straight to the fermenter, so I would think you would just add it toward the end of the boil/flameout, or when you're aerating the wort before pitching the yeast starter.
I would think it would be useful in both the starter and the brew.


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## Trough Lolly (11/8/04)

Deebee,
George De Piro wrote an interesting article on this yeast nutrient, here if you want to read it. He suggests that you can make a better yeast nutrient with old yeast.
I use DAP, occasionally, in the last 10 mins of the boil - I'm not too sure how good this stuff is and I may not buy any more in future... <_< 
Cheers,
TL


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## sosman (11/8/04)

HBS's seem to carry two types of yeast nutrient: DAP and "complete yeast nutrient" or something like that. I understand the second one contains DAP and dead yeast cells as well as maybe some trace elements.


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## Jethro (11/8/04)

At the winery I work at we use DAP for all ferments an add extra to bad ferments (where H2S is apparent) also use large amounts in yeast cultures. I reconif any is used at all in home brewing add to the boil late. Maybe airation of the wort would be more benificial. Dead yeast hulls are loaded with vitamin B which the yeasties love when stressed again I recon airation prior to fermentation is more imortant. 
Cheers Jethro


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## PostModern (11/8/04)

I think they're best used when you are making a high gravity and/or high adjunct brew, where malt based nutrients are not available to the yeast in sufficient quantity. I use the smallest pinch in my (DME) starters and 1/2 a teaspoon in big beers.

Can't really say if it's helped me at all, as every batch lately seems to be different. Been a while since my last stuck fermentation tho.


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## pint of lager (11/8/04)

Grape based ferments and barley malt based ferments should have all the nutrients that yeast need.

Anything else, like ginger beer, lemonade, fruit wines and meads need extra nutrients to avoid stuck ferments. Also, as mentioned, high grav and high adjunct brewing may need extra help too.

Usually, yeast nutrient is DAP. Yeast energiser is a mix of vitamins. Both are good. I would suggest a mix of both to provide the yeast with a balanced diet.

If adding to a brew, it is better to add straight to the fermenter, rather than to the boil as much ends up bound up in the hot and coild break and lost to the fermentation. If you are thinking about sanitation, boil the nutrient up in some water and pour into the fermeter.

If adding to starters, a little may be too much and toxic. Think how much you ad to a 23 litre brew, and then calculate how much you need in your microbrew starter.


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## deebee (13/8/04)

Thanks POL and others.


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