diammonium phosphate

There is an excellent article on DAP in the February issue of "Wines & Vines". It is one of those "damned-if-you-do and damned-if-you-don't scenarios, both excessively low YAN and Exessively high YAN can promote formation of urea, which can be transformed into ethyl carbamate, a likely carcinogren. None of these are problems any winery needs." In the wrong dosage or with the wrong timing, DAP can backfire, encouraging sulfur off-odors.

Note: YAN means yeast available nitrogen.

I believe the product Fermaid contains a small amount of DAP and may be safer to use, so unless you have a lab analysis of the YAN of your juice, be careful using DAP.

It's just as scary as sodium chloride. Any chemical can't be good for you.

Too much of either isn't a good thing, but in the right proportions both are useful.

DAP is a source of nitrogen used for grapes which are low in natural nitrogen content. Just don't put in too much, in which case you'll make ethyl carbamate which is a potential carcinogen. Use only what is necessary and you'll be ok.

Gene

The problem is that the only way to determine what is necessary is to have a lab test for YAN.

Don't get worried about the chemical names of things before you find out what they are.

Would you eat something that contained calcium phosphate, sodium hydrogen carbonate, calcium aluminum phosphate, and sodium aluminum silicate? Most folks would probably decline... unless they knew that the common name for that mixture is "baking powder".

Diammonium phosphate is a common yeast nutrient. Doesn't matter whether it's "good for a person" or not -- there isn't a significant amount of it left in the wine by the time you drink it, because the yeast already ate it. (It's harmless, BTW, at least in the quantities used in winemaking.)