What happens when I boil 2 pots of pasta in the same water back to back?

Question

I had to make 2 pots of pasta back to back. I did a pot of spaghetti as usual. I add a little vegetable oil always, salt, and I throw about 5 peppercorn seeds in the water, bring it to a boil, then add the boxed dry pasta.

Well, this time, when done, I took the spaghetti out of the boiling water (with tongs and a sieve. It was perfect. I then decided to do the linguini in the same boiling water. Was this a mistake? I just added a pinch more salt, and let it cook. When I thought it would be done, it was a little weird. Maybe chewy? I don't know if I'm just being paranoid and should just let it cook more.

Did I do a big pasta faux pas?

Answer 1

There should be no issue with doing this, restaurants often do this; the only thing that will happen is that the water will have more pasta starch as you cook more pasta in the same pot. Obviously, basic food safety rules apply here - you need to keep the water out of the "danger zone", but otherwise it should not be a problem.

This could be a good thing as far as helping the pasta bind to the sauce, but will possibly make the pasta a bit more sticky if you don't sauce it right away.

Answer 2

There is one possible complication here other than the food safety issue that Chris Macksey mentioned if you're not cooking it back-to-back:

• The water is going to foam more the second time as there's more starch in it.

You then might be tempted to turn the heat down some, or remove the lid from the pot, so you're not actually cooking both batches at the same temperature.

In your case, you added some oil to the water, so that will help to reduce the foaming process, so it might not be quite as bad as if you didn't.

If you're working solely off of the time to cook the pasta, you might need to give the second batch a little bit of extra time to compensate.

I personally always treat the times on packages as a guideline, as I cook enough different brands and shapes of pasta that I don't have it particularly "dialed in" -- so let taste be your guide. If you think it needs another minute, give it another minute.

I also add some water back to the pot between batches of pasta -- you've lost some water due to both evaporation and absorption by the previous batch of pasta that your water level will slowly go down, further concentrating the starches, and giving the pasta less room to move about freely as it cooks.