Hot or cold water when cooking pasta?


Personally, I use cold water and heat it to the boiling point. Somebody told me that hot water from the tap contains more chemical. On the other hand, it’s more energy efficient if we start from hot water.

Which way do you use? If someone has a scientific background to explain it would be great.

(John Hartley) #2

We boil the water in the kettle and put that in the pan, which already has heat under it. Quickest way to get to boiling, I think.


Hot tap water comes out of the water heater, so it has been sitting for a while, thus tasting a bit stale because it’s no longer aerated like out of the tap.

If you have a tank-style water heater, then yes, there are more chemicals (calcium, rust from the tank, etc) in that water, plus nasty things like lead from old pipes, etc. The crud that collects in your hot water kettle is a good sample of what the inside of your hot water heater looks like.

A more energy-efficient way to boil water is to heat a kettle full of cold, frsh water, then pouring that into your pasta pot. The kettle is faster and more efficient than the stove top.


Always start with cold tap


I use hot tap water, but I live in an apartment building with more than 400 units. The hot water doesn’t sit around like it would in a single-family home.

(Giovanna) #6

We use cold water from the tap, bring it to a rolling boil, boil for more than 5 min, then throw the macaroni (into the pot). Although we use filtered water we use that for soups, coffee, etc.

(erica) #7

That is debatable. I have read that the energy it takes to bring hot water to a boil isn’t much less than for cold. I believe Cooks Illustrated/ATK (or maybe Harold McGee) reported on this. Whether the water is heated by the stove, an electric kettle, or your water heater, it takes energy. Microwaving a quart of water, then adding it to unheated tap water, would probably jump-start the heating with the least use of energy. If you have to run your water to get it hot, at least collect the warming water in a pot or jug and use it for something else, like washing up. Wasting water is a matter of ever-increasing importance.

More significantly, you can cook a pound of dry pasta in 2-3 quarts of water, rather than the higher volumes routinely insisted upon by authentic Italian cooks. Boil the water, salt it if desired, add pasta, turn off the heat, stir, cover the pot, and let it steep, adding 3-5 minutes to the cooking time o9 the package. If it’s stranded pasta, lift the lid and stir midway through. You’ll save water AND energy. Or, if you are organized enough to remember in time, soak your dry pasta in tap water for 90 minutes before cooking it, which cuts the cooking time to that of fresh pasta.

Whenever I turn off the stove or oven, I use the free residual heat to heat up a covered pot of water, which I then use for other cooking, or cleaning up. If the air is dry in winter, I leave the lid off, to humidify the house.

(For the Horde!) #8

Not entirely clear to me that this is correct. I won’t be surprised that it is the other way around.


it’s not science, it’s cooking - and if you’ve cooked much pasta you probably know not all pasta cooks “as your heart desires” in the same amount of time.

starting in boiling water one can control the cooking time.
starting in cold water introduces a long string of variable times and pasta reactions to living in cold to warm to hot to boiling water.

somewhere I’m sure there is an Italian grandmother who can explain how the starch in pasta reacts to cold/warm/hot/boiling water and why you should do it by “Method X”

there is the (actual / true / real) issue of “gunk and stuff” coming out of the hot water tank. frankly I’m not so sure it’s any different than showering in the “gunk and stuff” - but , , ,


Dried pasta is made by techniques and ingredients that mean it should be put into abundant, salted BOILING water, and stirred occasionally while it cooks in the continuously boiling water. Pasta should be cooked al dente (test it with you teeth) and removed immediately from the boiling water and drained (not necessarily well). Almost all native Italian pasta sauces, with rare exception, are of the type that taste best when you immediately transfer the hot pasta into the sauce, and perhaps cook it a bit longer in the sauce while stirring and tossing. (Hence, not draining the pasta itself much).

If you don’t care about any of these things, you can soak pasta, stew it, use less than boiling water – whatever your motive is. But Italian pasta is made with care and is meant to be cooked in abundant amounts of rapidly boiling salted water to produce optimal results when combined with sauce.


Cold water . I have a under counter water filter hooked to the cold water . No way I’m using the hot water coming from my water heater through old galvanized pipe to the faucet .


I don’t cook with hot water from the tap except for SV cooking. No need for the circulator to work harder than it needs to

(Susan) #13

I don’t think the OP is thinking of putting both pasta and cold water in a pot, then waiting for them to boil, just whether it’s better to fill the pot with hot or cold water before bringing the water to a boil and adding the pasta.



Actually the only time I will start from cold water is to cook hard boiled eggs. Throwing the eggs into boiling water will create a temperature shock and the egg crack.

(erica) #15

[quote=“naf, post:14, topic:2118”]
Throwing the eggs into boiling water will create a temperature shock and the egg crack.
[/quote] I thought that too, for the longest time, but I was wrong. I was, I thought, using Jacques Pepin’s technique for hard-cooked eggs: Prick the broader end of the egg with a pin or tack before cooking for 13 min, then right into ice water. But my eggs ALWAYS cracked despite the pinhole to let the air out. Then I watched a repeat. He was putting the eggs into boiling water. I was starting them in cold, beginning the timing when the water came to a boil. Once I began doing it his way, I never had another one crack. (I’ve since switched to steaming them, which seems to be THE secret to easy-peel eggs regardless of how old/fresh they are.)

(Susan) #16

I’ve been doing the same thing to boil eggs, but just read that Kenji Lopez-Alt says that promotes glued-on eggshells, and that you should drop the raw eggs into boiling water and time it from there. We’ll see.

(Susan) #17

Hey, Jacques and Kenji can’t both be wrong.

(erica) #18

Yours is a commonly- held opinion, but has not withstood the investigations of many food scientists and other culinary experts.


I’m not sure on this one . Soak the pasta for 90 min . Then move it from one vessel to the other with the boiling water . So you’re moving it twice . That’s more work . Sounds like it doesn’t plump up either . Also where’s my pasta water with the starch that I use for my sauce . I think I’m better off dropping the spaghetti in boiling salted water and waiting the eight minutes . I cook small amounts and do not use that much water .


and just in case anybody’s wondering – I had a coupon for Barilla’s new Pasta Pronto – a shorter pasta that you put into a skillet, cover with water, and bring to a boil, then add sauce to finish cooking.

Save your money folks – you end uup with pasta that tastes like it’s straight from the nearest school lunchroom.