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What is the effect of adding salt to the water when cooking pasta?

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    Also notice that the pasta will only absorb so much salt. This is nice because it means you can never add too much. Any remaining salt will go out with the water. May 29, 2011 at 0:46
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    Note that adding salt slightly raises the boiling point (though by a negligible amount at the concentrations used in cooking). Since it rases the boiling point, it means the water takes longer to come to the boil. Oct 29, 2014 at 16:11
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    @ThomasAhle That may be true, but in my experience the point where pasta becomes inedibly salty is far below it's saturation point.
    – user25798
    Jul 17, 2015 at 15:35
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    @DerrickWilliams I've noticed you've posted a few comments recently which just agree with something but don't add anything else; this is the purpose of the voting buttons (or the 'accept answer' button on your own questions).
    – dbmag9
    May 25, 2021 at 15:42
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    @dbmag9 ok. now I'm learning. May 26, 2021 at 0:40

11 Answers 11

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The salt adds flavor, but it also helps reduce the gelatinization of the starch in the pasta. The starch in food is the form of microscopic grains. When these grains come into contact with water, they will trap some of it (think cornstarch in cold water), but when the water is hot they swell up like balloons and merge with each other, and you have starch gelatinization.

Another thing you may want to add to the pasta water is some acid (lemon or cream of tartar). Tap water in most cities is made alkaline, which increases the starch loss from the pasta to the water, making the pasta stickier.

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    Starch gelation is by far the primary reason, flavour is a side effect.
    – Noldorin
    Aug 16, 2010 at 10:33
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    Personally, I don't salt. If you use copious amount of water and stir occasionally, you should be fine. Aug 16, 2010 at 18:37
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    @MichaelMior You don't salt the water? How does the pasta taste then? I can't imagine eating pasta that has not been salted. Sincerely, an Italian. :-)
    – splattne
    Sep 11, 2012 at 12:25
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    @splattne If you have a well-seasoned sauce, it doesn't matter if the water is salted. Sep 11, 2012 at 14:24
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    @MichaelMior for the sake of the truth, a friend of mine, after some blood pressure problem, has switched to saltless food and he told me that after some time, you start to enjoy the food without salt because you feel all the flavors spectrum. So, in our future dinner, please do not salt the water :). Sep 12, 2012 at 18:43
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It means that the pasta is seasoned as it is cooked. To see if this matters to you, cook up some pasta in plain water and then some in salted water and see if you can taste the difference.

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    And what is the difference? Assuming you'll add salt to pasta which was cooked unsalted, both turn out salty in the end, right? Apr 6, 2017 at 10:12
  • the difference is that the seasoning goes into the pasta when the water is salted, as opposed to the seasoning going onto the pasta and, unless you are eating pasta which has nothing but salt on it, it will be washed off by the sauce.
    – Sam Holder
    Apr 6, 2017 at 10:23
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    That's not true. Salt won't stay on the cooked pasta, it will dissolve almost instantly (unless you put a lot of it of course), so by the time you add the sauce there will be nothing to wash off. Apr 6, 2017 at 10:30
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    I can confirm this. I forgot to salt the pasta and it tasted so bland. I tried adding salt on top of the pasta, and that still did no good. Then, I tried reheating the pasta and put more sauce and chili flakes, but there was still a yucky bland taste lingering underneath the savory flavor of the sauce.
    – Some Guy
    Dec 22, 2022 at 22:35
  • I think whether salt matters (and how much) really depends on whether you can taste it in the final dish as opposed to just plain pasta. Aug 14, 2023 at 15:30
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The addition of salt has at least 2 things going for it:

  1. It does help keep the pasta from cooking into water, thus improving texture (less sticky/gummy). When less of the starch and protein is leached out of the pasta, it will foam less as well! (Perform the 2 batch test, side by side. The salted water will foam less, and it will be less murky when the cooking is done)

  2. It does improve the flavour (at least for most of us). Just don't go crazy with the salt, and you'll be fine!

Yes, you can omit the salt, and you can acidify the water, but neither will produce a finished product that I'd care to eat.

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Personally, I add salt to water to reduce the bubbling while the water is boiling and allows me to walk away from the pot for a minute. I hate it when the pot bubbles over and some water falls over the sides of the pot. Something about the salt changes the waters ability to create bubbles. This is just my observation.

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    Salt does not have the effect described in this answer. Oct 19, 2014 at 21:25
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    @DavidRicherby you're wrong, salt does reduce the amount of foam/bubbles when cooking pasta, which helps prevent it from boiling over. Nov 29, 2016 at 12:25
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    @AbhiBeckert Every time I cook pasta, I put salt in the water. Actually, quite a lot of salt. It still boils over every time, unless I'm very careful with the lid and the heat. So my own experience is that salt does not suppress boil-over to any useful degree. Nov 29, 2016 at 13:16
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    @DavidRicherby To any useful degree and does not have the effect in this answer are totally different statements. And yes, the answer is correct. Try cooking your next 2 pastas without lid but with salt and no salt. Apr 12, 2019 at 11:14
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As has been mentioned, whether you add salt or not it is for taste. Salt will decrease the amount of time to boil, but only if used in significant quantity. 80% water 20% salt will only increase the boiling point of the water 4 degrees. The same volume of straight water will take longer to boil for the simple fact there is more water.

Pasta sticking is in large part due to the water itself. Most tap water is leans to the alkaline side of the chart. Adding some vinegar or lemon juice to water to raise its acidity will keep the pasta from sticking. How much? You'll have to experiment.

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  • If salt is added to decrease cooking time instead of taste, but must be added in quantities higher than anyone uses to have an effect, isn't it more likely that it's added for taste?
    – SourDoh
    Jan 21, 2014 at 23:36
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    This is incorrect. Adding salt slightly raises the boiling point (though by a negligible amount at the concentrations used in cooking). Since it rases the boiling point, it means the water takes longer to come to the boil. Oct 19, 2014 at 21:24
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    With higher boiling point, food cooks faster. But it is mostly inapplicable in case of pasta due to cooking time not significantly long enough, and amount of salt is too little to increase the boiling point anyway. If boiling point is the objective, using pressurized cooker would be better. Then again, the pasta might get smashed into soup in such utensil.
    – syockit
    Feb 3, 2015 at 9:55
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I have found that adding salt to pasta water helps the pasta hold the water when it comes in contact with the salt in the sauce. When the pasta was not cooked in salted water it weeps when sauce is served on top of undressed pasta. Dont know why? Just an observation.

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I guess it's like trying to sear a meat over a very high heat; the higher the temperature of the water the faster the pasta gets cook (so that it doesn't absorb too much which will expand the starch contain in the pasta) meanwhile leaving the center a a tiny white dot which creates a snap when bend. Besides that I too believe besides adding flavor to the pasta, by adding olive oil to the pasta is to avoid pasta from being stick together like a lump meanwhile stirring them to ensure equal heat is all over the pasta that is being cook. Olive oil to helps to coat the pasta which will reduce the water absorbtion and in the same time increase the water temperature even more higher.

The water doesn't need to be salty like totally salty but by just adding enough salt just enough for tasting will be good enough.

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    The amount of salt you would have to add to the water to make its boiling point significantly hotter would be enormous. For sugar, you start with a 3:2 water:sugar solution, which still has a boiling point of 100°C, and it only gets higher after lots of evaporation. Similar for salt.
    – rumtscho
    Jul 30, 2012 at 18:09
  • Oil will de-foam the water and reduce the amount pasta sticking together, it will also stop the pasta sauce from sticking to it when serving :-( A quick stir two or three time during the first two minutes of cooking will stop the pasta sticking together :-)
    – TFD
    Jul 30, 2012 at 23:49
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I am really surprised that there was no answer above relating to the simple fact that adding even half a teaspoon salt to the boiling water serves this purpose:

  1. the sodium helps fill water molecules, which...
  2. reduces the transfer of vitamins, especially B-vitamins from noodles into the cooking water...
  3. which then gets thrown out as one drains the boiled noodles along with all those vitamins in that water.

That's also why I have stopped rinsing the boiled noodles, which washes off and leaches out more vitamins down the sink-drain.

If you drain noodles after boiling and don't want them to stick together, just run a Stick of butter very fast through the whole batch, which immediately improves the flavor, or put your thumb almost totally over the top of a bottle of first-pressed olive oil, and sprinkle a teaspoon or so over that batch of noodles and stir fast.

I have thereby never had any problems of sticky lumps, when stored in the refrigerator, and I have preserved a better level of nutrition.

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    How do you mean, the sodium helps fill water molecules? Do you have a source for this? Jun 27, 2013 at 8:59
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    Even assuming that your theory is right, which I doubt very much, it doesn't matter. Noodles are typically made from refined semolina, and will therefore have a negligible amount of Vit B (and other vitamins) to start with. One would have to eat whole grain noodles to get any vitamins from them, and these are in my experience a niche product.
    – rumtscho
    Jun 27, 2013 at 10:49
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it is actually to help the pasta absorb water.. it's done with meat chicken fish also..

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    Hi Jim - can you give us some more detail about how that works, with references if possible? This site is after a bit more than one-sentence answers. Jul 24, 2013 at 9:06
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Aside from the flavor implications of adding salt, salty water has a higher boiling point than pure water, so you can cook whatever you are boiling at a higher temperature. The more salt, the higher the boiling point, up to the limit of a fully saturated solution.

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    This is a myth: adding salt changes the boiling point by a fraction of a degree at best.
    – Marti
    Nov 7, 2010 at 2:52
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    It needs to be quite salty to make a significant move, but the effect can be measurable. It's roughly 3 tablespoons per quart to move the boiling point one full degree Fahrenheit. Which is somewhere in the same ballpark of boiling point change as 1/8 of a mile.
    – wrosecrans
    Nov 7, 2010 at 20:43
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    Three tablespoons per quart is a ton - more than 1.5x as salty as seawater. And a difference of 1°F in water temperature makes basically no difference to the pasta cooking - you can even cook pasta in 200°F water (not even boiling!) and you won't be able to tell the difference. What you will notice from adding that much salt, however, is that your pasta ends up unbearably salty.
    – Cascabel
    Apr 26, 2013 at 23:12
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It has to do with Osmosis (https://en.wikipedia.org/wiki/Osmosis). The saltier the water the less water gets pulled in by the pasta. Adding salt will keep your pasta nice and firm and not too bloated. That is also why you should never drink distilled water in Chemistry class. The exact opposite will happen, since there are no Salts in distilled water, your cells having a higher salt level will pull in all the water literally making them pop.

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  • I hate to say it, but that is simply not true. Sure one drop will do little harm, but a full bottle will most definatly kill you. Even regular water can be harmful in high enough dose. It often happens that little kids with a low body mass do drinking games with water and end up in the hospital. With Distilled water the dose needed to seriously cause harm is much lower. I do not make a habit of responding to people with a clear lack of education in a certain field, but since kids might read this i did feel the responsibility to make it clear that this is in fact very dangerous.
    – Geen naam
    Jan 13, 2016 at 11:37
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    Logic: Dangerous chemicals (e.g. bleach, drain cleaner) have extensive warnings (keep out of reach of children, call poison control if ingested, etc). A gallon jug of distilled water has no warnings on it. Science: Water intoxication (medical term: euvolemic hyponatremia) is a danger because of sodium imbalance, not cells exploding (osmotic lysis). Long term (i.e. years) drinking only distilled water can cause dangerous mineral imbalances, but one bottle won't "definitely kill you."
    – Erica
    Jan 13, 2016 at 12:44
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    In addition to the articles and information I have linked to in my comments, I also suggest you read the StackExchange "Be Nice" policy. Constructive feedback about erroneous information is welcome, but insults like "people with a clear lack of education in a certain field" are not. Not only is it simply rude, but your own argument is weakened when you resort to personal attacks to make your point.
    – Erica
    Jan 13, 2016 at 13:03
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    No. The reason you don't drink distilled water in chemistry class is that you don't know how clean the distilled water storage is and you don't know how clean is whatever vessel you're using to carry the distilled water. Either or both of them could be contaminated with bacteria or chemicals. If that contamination messes up your experiment, that's annoying; if it poisons you, that's a really big deal. You don't drink anything in chemistry class. Nov 29, 2016 at 13:20

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