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Diammonium Phosphate Overdose???

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Luke7e

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My 1 lb bag from L.D. Carlson stated 1 tsp per gallon....now I am reading that it is 1 tsp per 5 gallons???? Am I just going to have a hyper speed fermentation in my conical or do I need to be worried about poisoning my customers???? Is there a negative to what I did. I have 35 gallons in my conical right now and don't want to have to dump it if I don't have to...
 
Doesn’t it say "UP to 1 tsp per 5 gallons???"

I'm far from an expert, but I have found the use of DAP beneficial to prevent under attenuated wort. However, my dosage per 6 gallons is 1/4 teaspoon. Too much zinc can cause yeast to produce off-flavors.
 
My 1 lb bag from L.D. Carlson stated 1 tsp per gallon....now I am reading that it is 1 tsp per 5 gallons???? Am I just going to have a hyper speed fermentation in my conical or do I need to be worried about poisoning my customers???? Is there a negative to what I did. I have 35 gallons in my conical right now and don't want to have to dump it if I don't have to...

From Morebeer it says:

Use .5 - .75 grams per gallon , about 1/2 tsp per 5 gallons
http://www.morebeer.com/products/yeast-nutrient-dap-2-oz.html

Midwest and Northern Brewer say the same thing.


You may have used 5-10 times too much.
I doubt anything bad will happen though.
For next time I'd use the 1/2 - 1 tsp that is suggested on the label.
 
From Diammonium Phosphate MSDS sheet for fertilizer:

"Ingestion (Swallowing): Low degree of toxicity by ingestion

TOXICOLOGICAL INFORMATION:
LD50 (oral, rat) = 6500 mg/kg, >2 g/kg; (Which is g/(kg of body weight) taken orally by rats to kill 50% of the population.)
Inadequate mutagenicity, target organ or developmental toxicity data located for diammonium phosphate.
No carcinogenicity data located for diammonium phosphate."

if we use 2g/kg, then 3g/gal -> .375g/pint, so a population of 180lb (82kg) rats would have to each drink 437 pints all at once to kill half the rats at the pub?

That's just back-of-the-napkin calculation by a lay person, but someone needs to double check that. :)

However the yeast are going to consume some of that in some way, right?


edit: Turns out that the weight is about 3g in a tsp. I screwed up the calc using molecular weight. I corrected my numbers above. This looks a lot better, but someone please check.
 
So I checked the bag again and it says Yeast Nutrient Diammonium Phosphate and Urea... 1 tsp per gallon must so maybe I am safe? I will say that the fermentation is going balls to the wall with my blow off tube making huge bubbles in the star san...

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I'm definitely interested in the results. Please update this thread.
 
I've had a few off tasting brews where I used too much of this but it could also have been down to not aerating well enough. They ended up with too much banana and spice but there weren't fusels. Both were with saison yeasts (French saison and some from blaugies bottles)
 
if we use 2g/kg, then 3g/gal -> .375g/pint, so a population of 180lb (82kg) rats would have to each drink 437 pints all at once to kill half the rats at the pub?
... someone please check.

A) I don't have 437 pints per rat to spare on testing whether rat consumption of same would eliminate half the rat population, nor do I have or wish to find a rat population to test

B) <something pithy about goats>

Seriously though, I've way overdone DAP accidentally on starters and not had off flavor issues or any ill effects, except perhaps the overwhelming need to make smart alec comments
 
Just revisiting this thread and adding a comment and hope to get some response.
Yesterday we brewed an american lager OG of 1.052. Mashed at around 5.2/5.3 pH and everything was good. I did not check the pH preboil but post boil after chilling the pH was 6.2. The only thing that could have increased this was the addition of urea and diammonium phosphate (same bag as Luke7e post 6/23/15). It was added in a rate of 0.5 tsp / gallon of wort in the last 15 minutes of boil. Has anyone ever noticed such an increase by the use of this nutrient. And if so, is there a down side?

I have always used servomyces and have never see a pH change from this addition, maybe because the gram addition is so small.

pH levels pre-fermentation are usually 4.8 - 5.2 from what I have seen and this occurrence is out of the ordinary.

Any comments or thoughts would greatly be appreciated.
 
Aside from wanting to hear another funny ass post from balrog, I would like to hear what the group has to say about this as well.
 
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