Just my opinion, much like the green tinge around the yolk of a hardboiled egg it oxidation. I've had this happen and it's only the outer skin that's green, the center is fine. A quick need and the color returns to normal. Taste of the final product was fine.

You should use semolina flour or 00 flour. More traditional. You'll find the flavor improves as well as the texture. Also, dough in the freezer will only last a couple weeks.

Because you left in the fridge...

Don't do that.

Yeah, the discoloration is essentially the eggs going bad. Since fresh pasta has egg yolks in them they are extremely perishable. The only reason eggs stay god for as long as they in the fridge is because they are hermetically sealed in their own shell. When exposed to air, bacteria develops in the eggs at an exponential rate. Remember eggs are essentially a life sustaining food for the babies that live inside of them, so they are full of yummy stuff that bacteria love to eat. Once pasta dough comes together you should use it immediately, as the egg yolks will begin to deteriorate quickly, that green color is essentially rotten eggs. As others have already mentioned, go with freezing your day if you don't plan on using it right away, but as try using it the day of creation if possible.

No matter what kind of dough you make, it will turn a sickly gray/green color after a day or two in the fridge. There are three ways to avoid it: 1. Use it all right away; 2. Store any excess in the freezer; 3. Use bleached flour. Stay away from #3--unbleached flour is more processed and the dough won't be firm or as easy to handle than when unbleached flour is used.

better safe than sorry! :) I'm not sure what the acid might do to pasta dough, so who knows if it woulda worked to begin with.

I think it has something to do with the sulfur in the eggs that causes that. I usually freeze my homemade dough if I know I won't be using it within a couple of days. For whatever reason, the green tinge never shows up in my frozen dough, only if it's been refrigerated. If it smells fine, I would probably use it as well, like campagnes suggests.

No...I was scared and threw it out....thanks for the info :)

As part of a work-related retreat, I had to prepare three breakfasts for about 75 people over the course of a weekend. The first night, I cracked and beat about a zillion eggs so they'd be ready to use for omelettes the next morning. And I woke up the next morning to find that some of the egg in the bucket had turned a bizarre shade of olive green. They were perfectly fine - just discolored. For the rest of the weekend, I experimented with adding a small shot of white vinegar to the eggs before stashing them for the night and never had discoloration issues again. So I'm not sure what causes it, but apparently adding a small amount of acid might help stave off discoloration, at least in my limited experience. Are you planning to use the dough anyway? (I would!) :)