"Prepared" on food labels

[matt_mcl]

I have in my kitchen a jar of Maille Dijon Original Prepared Mustard. What exactly does "prepared" mean in this context? What would "unprepared" mustard be?

[Duck Duck Goose]

Just off the top of my head, "prepared" means they've ground up the mustard seed for you and mixed it with vinegar. "Unprepared" mustard [here DDG heroically avoids making the inevitable Boy Scout joke] would be mustard seed au naturel.

[SmackFu]

The entry on Prepared Mustard (http://www.allrecipes.com/encyc/terms/M/7566.asp), from the Cooking Encyclopedia.
Prepared MUSTARD is generally made from powdered MUSTARD combined with seasonings and a liquid such as water, vinegar, wine, beer or must.
So you need the modifier on the word mustard to distinguish it from its component ingredient.

[Jenericho]

Here in Britain, the best selling mustard (Coleman's English Mustard) can be bought as a powder or ready-made. You just mix the powder with water to make it usable.

Much the same as that other yellow kitchen staple, custard.