# Why is it important to put salt in cold water for cooking potatoes?



## french fries (Sep 5, 2008)

I was reading a Robuchon cookbook. He's explaining how to cook potatoes in boiling water, and he explains that the salt should be put in the cold water along with the potatoes, before turning the heat on. A little later in the text, he insists: "and remember, there's a reason why you should put the salt at the very beginning of the cooking". 

Anyone knows what that reason is? 

Thanks!


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## phatch (Mar 29, 2002)

It gives the potatoes time to absorb the salt somewhat. So it's about flavor.


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## french fries (Sep 5, 2008)

Great, thanks Phatch.


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## chefbillyb (Feb 8, 2009)

I think it may be a bit more important when using the potatoes for potato salad. I don't think it really matters if your making mashed potatoes, your going to season anyway...........6 of one half a dozen of another....ChefbillyB


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## french fries (Sep 5, 2008)

ChefBillyB said:


> I think it may be a bit more important when using the potatoes for potato salad. I don't think it really matters if your making mashed potatoes, your going to season anyway...........6 of one half a dozen of another....ChefbillyB


Thanks ChefBillyB, however in this case, this was for Robuchon's famous mashed potatoes recipe (Robuchon became quite famous for his fabulous mashed potatoes in France), and apparently, from the way he wrote the recipe, the salting of the cold water was a very important step, I just wish he'd explained why.


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## chefbuba (Feb 17, 2010)

Anything will taste good with a 2:1 ratio of potato to butter!


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## granny smith (Jan 31, 2011)

I've tried boiling potatoes with and without salt. They don't seem to get as soft without the salt in the water. I don't know why. I've noticed the same thing with noodles. The outside gets tender, but the inside is still hard (potatoes _and_ noodles)


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## koukouvagia (Apr 3, 2008)

I thought it wasn't good to put salt in a stainless steel pot unless the water was already boiling.  Doesn't it ruin the cookware?


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## brianshaw (Dec 18, 2010)

My grandmother did this back in the days before Messr Robuchon and his wonderful cookbook. She insisted it was essential. And she was Irish and lived in Maine... so she knows about potatos!

The reason she told me was because it is too easy to forget to salt the water if you don't work in an organized and methodical way. I think she's right.

My wife does nto subscribe to this philosophy so I often have a burn on one of my fingers since I'll dip a finger in the boiling pot to check for salt in the water. It is better to get it in "too late" than not at all.

The only danger I know of from adding salt to boiling water is that it causes the water to "explode" when the salt is added. That never happens if salt is added to cold water.



French Fries said:


> Anyone knows what that reason is?


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## brianshaw (Dec 18, 2010)

I think that's how those rust spots get on the bottom of stainless steel pots.



Koukouvagia said:


> I thought it wasn't good to put salt in a stainless steel pot unless the water was already boiling. Doesn't it ruin the cookware?


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## phatch (Mar 29, 2002)

It won't damage your cookware  in the time it's concentrated before it dissolves. If you're worried about it, stir it as you add it to speed up the dissolving .


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## benway (May 24, 2009)

The important part here is that you put the salt in cold water, its that you put the salt in before the potatoes.  The idea is to season the potatoes from the inside.  The purpose for starting both the potatoes and salt in cold water is that the gradual temperature increase will help the potatoes cook more evenly as opposed to dropping quartered potatoes in already boiling water where the edges/outside will be overcooked by the time the center is done.


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## wldbeast (Sep 8, 2014)

Question why add salt at the beginning of the cooking process and not at the end. I actually do both the salt added at the beginning changes the chemical makeup of the water and the density. Allowing it to come to a boil quicker. I also have started the water under heat and just before it boils add the salt usually the water immediately boils.

I adjust the salt after the cooking process by adding salt to taste, but I'm a believer in salt and pepper are personal choices and not everyone has the same reception or even the same amount of receptors.

WB


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## chefedb (Apr 3, 2010)

Some people think salt makes water a lot hotter. It actually raises the  temp. about 2 degrees only. Don't believe me test it with a thermometer. Only thing I can say is that its' habit.. As  Chef Bubba says'' butter in particular amount he uses in his potatoes would have to taste   good''


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## phatch (Mar 29, 2002)

wldbeast said:


> Allowing it to come to a boil quicker. I also have started the water under heat and just before it boils add the salt usually the water immediately boils.


It won't boil quicker. It raises the boiling point fractionally, but so little it doesn't matter. You have to add a large quantity of salt to appreciably raise the boiling point. Chefeds claim of 2 degrees is interesting, but I suspect an error of some sort to see that large of a jump in temp as that would take a fair amount of salt.

The reaction you see when you add salt to nearly boiling water is about nucleation sites. You'll see the same thing happen along a scratch in the pan, or around the tines on a fork you hold against the bottom of a pot.

http://www.newton.dep.anl.gov/askasci/gen01/gen01021.htm


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## saw1958 (Nov 14, 2015)

I have a BS in science as well as a BA in Art & Graphic Design. The reason I found to add S A L T to cool water is really just to add it right before cooking to increase the boiling point. This means the water will take " longer" to boil because it will boil at a higher temp. Now, the reason for this is....How many of you boil on high and the water foams up and boils over ruining your stove and food? It is a small change in BP so I would still try "Med High" or even "Medium" to boil those taters instead of "High".


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## phatch (Mar 29, 2002)

The boiling point change is insignificant in the amount of salt used. 

The boiling point is raised by 0.5 degrees Celsius for water with 29.2 grams of salt dissolved in each kg of water. That's over an ounce of salt in a liter of water for about 1 degree fahrenheit.  About 2 Tablespoons of Kosher Salt into a liter of water. 

Considering I'm boiling water at 200 degrees at my elevation, then I'd say we need to worry about elevation a lot more than salt in the water for extra heat.


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## kuan (Jun 11, 2001)

The potato will suck the salt either way.  Remember there's that trick where we put a potato in the soup if it's too salty.

Besides, I'm guessing after you cook and mash the potatoes it's all basically brine and potato so what's the point?


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## mr jerry10ml (Dec 24, 2015)

There is no logical reason to put salt in water before boiling taters.... the only thing that salt does is raise the boiling point of the water. Most that do add salt,  is because they have seen someone else do it......(without explanation). By the way...if you add salt, the rise in temperature is miniscule........so,   keep your salt for where it's needed.


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## flipflopgirl (Jun 27, 2012)

Mr Jerry10ML said:


> Most that do add salt, is because they have seen someone else do it.....


My mom made the best roast beef (Pikes Peak cut) in the world.

So good that the preacher and family were always invited making us a party of almost 20 ppl .

So she would do a REALLY big hunk o meat.

I noticed she always cut the meat in half before browning and covering to braise on top of stove.

So for years I always followed her recipe exactly.

One day my sister was over and observed the whole process and asked me why I did it.

Well SISTER this is the way mom always did it.

I thought she was gonna bust a gut laughing.

Turns out mom's dutch oven was not tall enuff to hold a huge piece of meat and cover as well.

So she had to make it fit.

Which meant cutting it into two equal size chunks and fitting it into the pot like a puzzle.

To say I felt pretty dumb was an understatement /img/vbsmilies/smilies/crazy.gif lol.

mimi


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## jock (Dec 4, 2001)

So, it turns out that the chemistry involved in salting potato (and pasta) water is hugely complex. Scientific studies have been done on the effects of salt on starches. They talk about salting-in ions which reduce the gelatinization of starches and salting-out ions which increase starch gelatinization.

The sodium in sodium chloride is a salting-in ion and so reduces starch gelatinization, while the chloride is somewhere in the neutral zone. So, while most of us salt our potato and pasta water to make the food taste better (and salt does that very well too) there is another reason Robuchon insists on salting the cold water for his potatoes. It is reasonable to suggest that the state of the starches in the cooked potatoes will affect the texture, if not the taste, of the finished mashed potatoes. 

I should point out that this is a simplified explanation of a very complex subject of which I have only a rudimentary understanding. That said, it has been my experience that nothing in cooking is "just that simple". Behind all that we do as cooks there is a world of science. 

Jock


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## maryb (Mar 21, 2008)

flipflopgirl said:


> My mom made the best roast beef (Pikes Peak cut) in the world.
> 
> So good that the preacher and family were always invited making us a party of almost 20 ppl .
> 
> ...


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## maryb (Mar 21, 2008)

Mr Jerry10ML said:


> There is no logical reason to put salt in water before boiling taters.... the only thing that salt does is raise the boiling point of the water. Most that do add salt, is because they have seen someone else do it......(without explanation). By the way...if you add salt, the rise in temperature is miniscule........so, keep your salt for where it's needed.


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## foodpump (Oct 10, 2005)

For me, it has nothing to do with flavour. Salt does not readily dissolve in cold water, it just settles to the bottom of the pot. Many cookware mnfctrs. ask that you not do this as heat plus salt will cause pitting, particularily with aluminum. Salt will dissolve almost immediatly in hot water though.


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## welldonechef (Sep 28, 2008)

The reason comes from why you put the potatoes in cold water first. If you put your salt in at the beginning, the potatoes will flavor as they heat through. If you add the salt later when the water boils, the potatoes will not be uniformly seasoned. 
I'm pretty sure that this was discovered by trial and error.


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