Australia's Science Forum

Hi all,
A question for the Chemists among us (of which I am NOT one!!)

My Chemistry Teacher asked for some Ammonium Phosphate as an ingredient for a fermentation prac, making ethanol. I could not find any Ammonium Phosphate on the shelf, so he had to go without. (experiment worked any way). When I went to the catalogue to order Ammonium Phosphate, the supplier had Di- Ammonium hydrogen Orthophosphate, and Ammonium Di-Hydrogen Orthophosphate (but no Ammonium Phosphate!). I asked the Chemistry teacher which one he wanted and he did not have a clue. Nor do I.

Does any one out there in "Chemtalk" land know which is the most likely chemical to aid the fermentation of yeast in a fermentation prac? What quantities would you use? What is it's function? (does it spoil the taste of the "Moonshine") Woops! delete that last question! (Hic)

regards
Ian

Never used ammonium phosphate, but in our recipe we use citric acid(only a few crystals). Not sure what it does. We have used it without and still work well.
Lada

Hi Ian,
Sorry, I can't actually help with your question, but could you tell me which catalogue you saw the Di-Ammonium hydrogen Orthophosphate, and Ammonium Di-hydrogen Orthophosphate? We use both of these in Chem, but my normal supplier has neither, and I'm running low. Thanking you in advance.
Cheers,
Lisa

From the CSIS Voleume 2 appendices page 38

Ammonium Dihydrogen Phosphate is a mineral nutrient for yeast culture media.

It is also known as Ammonium Dihydrogen Orthophosphate
Ammonium biphosphate, & Ammonium phosphate Monobasic, Cas No 7722-76-1.

So perhaps these names where once used.

Hope this may help a little Ian

Sorry you also asked what is the difference between.

Tribasic has 3 Replaceable Hydrogen atoms
MonoBasic has 1 Replaceable Hydrogen atom
Di Basic has 2 Replaceable Hydrogen atoms

So each one would have a different Molecular weight

Do that help any more

That helps a lot Sue. You are a wealth of information! I don't know what we would do without you and Robb!
Thanks again

Ian

Lisa,
I was looking at the catalogue from "Science Supply Australia" Education Catalogue '06/'07
They are at
web: http://www.chemtalk.com.au/viewtopic.php?f=26&t=451
Phone: 1300 857 544
Fax: 1300 857 533
Mail: PO Box 465, Glen Waverley, Vic 3150

It is always good to have another catalogue on the shelf!

regards
Ian

Northern Territory does a prac called population growth of yeast. It suggests to add ammonium dihydrogen phosphate "which supplies nutrients for the yeast and encourages them to start dividing" ( in the proportions of 1 drop yeast suspension + 10 ml 10% glucose solution + 0.1g of the phosphate)
Hope this helps or explains. Rosalie

HI All,

Just for everyones information, the Ammonium DiHydrogen Phosphate is ideal as the mineral nutrient for yeast culture media.

But don't get it confused with Ammonium Phosphate...

Ammonium Phophate is usually packaged as Anhydrous OR the common triHydrate.

This compound may be hard to find but it is not rare.. Becareful as Ammonium Phosphate (NH₄)₃PO₄.3H₂O is completely different to the Ammonium Dihydrogen Phosphate..

Cheers,

Robb.....

Not sure if this is correct or is any help but the MSDS that I have for Ammonium Phosphate has one of the synonyms as Ammonium Orthophosphate and its product use is "Flameproofing of wood, paper and textiles." most likely not what you are looking for.

I have ammonium phosphate tribasic, ammonium dihydrogen phosphate and diammonium hydrogen phosphate. Are these three all one and the same, just different names?

I just googled the names and the formulae are (NH4)3PO4, NH4H2PO4, and (NH4)2HPO4 respectively. So they are different substances.

Bit late to the party , but to answer the OPs question , di-Ammonium phosphate is what is used in wine making and in distilleries . It is commonly called DAP .