Salt

[Cuddles]

Two things about it, the first of which is actually to do with science. When cooking somwthing like rice in water, if salt is added to the water, how much will actually end up in the rice? I would have thought most of it would stay dissolved in the water, so very little should be eaten. If this is the case, are all the warnings telling people not to salt water when cooking actually pointless?

The other thing I noticed is that all the warnings about salt say we should not eat more than about 6 grams of salt per day (or at least the one in the canteen at work does). I have never seen food labelled with salt content, it always has sodium content. Does this mean that they are simply calling salt sodium, or should they be warning us to eat less than 3 grams of sodium per day? If the latter, surely all the warnings are useless, since the average person is unlikely to notice the difference between the warnings and the actual labels.

 

[nimzov]

Two things about it, the first of which is actually to do with science. When cooking somwthing like rice in water, if salt is added to the water, how much will actually end up in the rice? I would have thought most of it would stay dissolved in the water, so very little should be eaten. If this is the case, are all the warnings telling people not to salt water when cooking actually pointless?

I don't know how much is absorbed, but I think that adding salt to water has to do with raising the temperature of the boiling water to 106^oC and thus reducing the cooking time.

nimzo

 

[Katana]

The USDA suggests not consuming more than 2400mg of sodium daily (the rough equivalent to a teaspoon of table salt). Sodium makes up roughly 40% of sodium chloride (salt), so multiply 2400 x 2.5 and you get the 6000mg (or 6g) recommendation that you saw.

Perhaps a useful way to remember: salt = sodium x 2.5

Some people may consider salt to be synonymous with sodium, but it's really the sodium recommendations that food label percentages are based on (i.e. why a serving with 480mg sodium contains 20% of the recommended daily allowance). If you go by the 6g rule, you may think you're doing great.

I don't know if that helps or not.

As for the rice question, since the water containing the salt is absorbed by the rice, wouldn't all of the salt end up in the rice?

What I don't know is how much salt is absorbed by something like pasta that absorbs only a small amount of the cooking water. Probably depends on the a variety of factors. For one, I doubt that fresh pasta would pick up as much as dry.

 

[Katana]

I don't know how much is absorbed, but I think that adding salt to water has to do with raising the temperature of the boiling water to 106^oC and reducing the cooking time.

nimzo

I used to think that, too, until I forgot to put salt in rice once. Yuck.

 

[kmortis]

Two things about it, the first of which is actually to do with science. When cooking somwthing like rice in water, if salt is added to the water, how much will actually end up in the rice? I would have thought most of it would stay dissolved in the water, so very little should be eaten. If this is the case, are all the warnings telling people not to salt water when cooking actually pointless?

The other thing I noticed is that all the warnings about salt say we should not eat more than about 6 grams of salt per day (or at least the one in the canteen at work does). I have never seen food labelled with salt content, it always has sodium content. Does this mean that they are simply calling salt sodium, or should they be warning us to eat less than 3 grams of sodium per day? If the latter, surely all the warnings are useless, since the average person is unlikely to notice the difference between the warnings and the actual labels.

If you're only talking rice, quite a bit, if not all, of it would end up in the rice as if the rice is properly cooked, it should absorb all the liquid it's cooked in.

If you expand this question to other boiled foods (ie frozen veggies or potatoes), then the amount would lessen. I know that Alton Brown tell you to salt your pasta water 'cause it's "the only time to season the pasta". I'd imagine that the amount absorbed would be related to how porous the food is. A potato would absorb more than a wax bean would, say.

I don't know how much is absorbed, but I think that adding salt to water has to do with raising the temperature of the boiling water to 106^oC and reducing the cooking time.

nimzo

Actaully, this is not entirely true. I know someone here once did this as an experiment in the chem class that they taught (I think it was athon, but don't quote me, I just remember that they were in the British school system) and found that the difference was so slight as to be negligable.

 

[nimzov]

Actaully, this is not entirely true. I know someone here once did this as an experiment in the chem class that they taught (I think it was athon, but don't quote me, I just remember that they were in the British school system) and found that the difference was so slight as to be negligable.

I agree that adding a bit of salt won't change much the boiling point of water. I think you have to add about 25 grams of salt to one liter of water to raise the boiling temperature to 106.

That is quite a large amount of salt in cooking.

nimzo

 

[NeilC]

Depends how you cook your rice.

If you use a large pad of water and strain the rice then not so much but the method I use (water to 1.5 times volume of the rice) leaves the pad empty so all the salt must be in the rice.

 

[joobz]

I always thought people salted water they were going to boil to reduce the lag time before the boiling started.

If you add salt (in the form of kosher or large granuals), you have nucleated sites which can help reach a boil sooner.

 

[russingram]

I've seen people cook rice like pasta (i.e. large quantity of water, strain the rice when it's done), but my Amah in Hong Kong taught me to add rice to the pot, add an amount of water that covers the rice to a depth equivalent to the length of your first index finger joint (i.e., to the first knuckle), bring water to a boil, reduce heat to low, cover the pot, and cook for 20 minutes (don't peek!). Fluff with a fork, and serve. This seems to work with any size pot and any size finger. It doesn't work with large quantities, though (more than 2 lbs of rice).

Anywho, with this method, all the water is absorbed by the rice, therefore, so is the salt.

 

[Cuddles]

Just to clarify, I meant any food cooked in water, not just rice. There is so little salt used that it can't make a difference to the boiling temperature. Nucleation sites can't make any difference if you've got a pan full of food, if you boil the water first, this would be done in a kettle without salt anyway. I'm pretty sure that the only difference the salt makes is to the taste (although I don't notice that either), I was just wondering if there could actually be enough used for there to be any reason to warn against it.

Katana - The problem I have is that our health advice talks about salt (at least I have never seen any mention of sodium), while food labels talk about sodium. What you say is entirely true, but anyone without an understanding of chemistry won't know this, so the advice seems fairly useless if people can't compare the health advice with what they are actually eating.

 

[kmortis]

Just to clarify, I meant any food cooked in water, not just rice. There is so little salt used that it can't make a difference to the boiling temperature. Nucleation sites can't make any difference if you've got a pan full of food, if you boil the water first, this would be done in a kettle without salt anyway. I'm pretty sure that the only difference the salt makes is to the taste (although I don't notice that either), I was just wondering if there could actually be enough used for there to be any reason to warn against it.

Depends on how hypertensive (or other salt-sensitive disorder) you are. I know that some heart paitents are told simply do not add ANY salt, ever. Others can get away with a little. Me? I always add at least a little salt to any boiling water or sautee (excepting mushrooms who get salted at the end of the cooking process).

And you'll rarely ever notice the salt if it's properly added, but you'll defiantly notice if it's not there. Salt helps bring out certain flavors, as does alcohol, oils and other additives.

Besides, it's the only rock we eat.

 

[Katana]

Katana - The problem I have is that our health advice talks about salt (at least I have never seen any mention of sodium), while food labels talk about sodium. What you say is entirely true, but anyone without an understanding of chemistry won't know this, so the advice seems fairly useless if people can't compare the health advice with what they are actually eating.

I hear you. Do you live in the UK? The reason why I ask is because, when I looked up the 6g recommendation that you mentioned, I found sites, including one from the government, primarily in the UK.

From http://www.food.gov.uk/multimedia/faq/readymealqanda/:

If you want to make a healthy choice when choosing which food products to buy, you might find it useful to check the nutrition information on the food label. Information is usually given about the sodium content. There are about 2.5g of sodium in 6g of salt.

Use the following rules of thumb to judge a little or a lot of sodium in ready prepared foods including ready meals:

0.5g sodium or more per 100g of food = a lot
0.1g sodium or less per 100g of food = a little
Quantities between these figures mean the product has a moderate amount of sodium.

It does seem silly to stand by the 6g of salt recommendation but have food labels in mg of sodium. The U.S. seems to stick with sodium content as the focus of recommendations, which is consistent with the food labeling in the country.

 

[Cuddles]

Depends on how hypertensive (or other salt-sensitive disorder) you are. I know that some heart paitents are told simply do not add ANY salt, ever. Others can get away with a little. Me? I always add at least a little salt to any boiling water or sautee (excepting mushrooms who get salted at the end of the cooking process).

Yes, they are told this. But why? If you add half a gram of salt to a pint of water, and then throw most of it down the sink when you drain it, how can you possibly be getting any significant amount? I would be surprised if it was even measureable.

I hear you. Do you live in the UK? The reason why I ask is because, when I looked up the 6g recommendation that you mentioned, I found sites, including one from the government, primarily in the UK.

From http://www.food.gov.uk/multimedia/faq/readymealqanda/:

It does seem silly to stand by the 6g of salt recommendation but have food labels in mg of sodium. The U.S. seems to stick with sodium content as the focus of recommendations, which is consistent with the food labeling in the country.

Yep. Silly UK. And to think we mock you Americans.

 

[Katana]

Yep. Silly UK. And to think we mock you Americans.

Eh. So we got one thing right.

 

[fuelair]

I don't know how much is absorbed, but I think that adding salt to water has to do with raising the temperature of the boiling water to 106^oC and thus reducing the cooking time.

nimzo

NO!! you have to add LOTS of salt to raise the temp just a little. Salt is to help remove starch - soaking gets some, heating while soaking gets more, heating while soaking in salt water gets even more. Applies to pasta and potatoes. NOT to beans (salty will harden them), most veggies, etc. Sodium is the problem in salt (sodium chloride). Whatever the mass of salt is, sodium is right at 40% so 6 grams of sodium requires 15 grams of salt.

 

[ponderingturtle]

If you're only talking rice, quite a bit, if not all, of it would end up in the rice as if the rice is properly cooked, it should absorb all the liquid it's cooked in.

If you expand this question to other boiled foods (ie frozen veggies or potatoes), then the amount would lessen. I know that Alton Brown tell you to salt your pasta water 'cause it's "the only time to season the pasta". I'd imagine that the amount absorbed would be related to how porous the food is. A potato would absorb more than a wax bean would, say.

Alton also had a individual on his salt show claiming that for 90% of the population with out sodium related hypertension, that excess salt is not much of a problem

Actaully, this is not entirely true. I know someone here once did this as an experiment in the chem class that they taught (I think it was athon, but don't quote me, I just remember that they were in the British school system) and found that the difference was so slight as to be negligable.

That all depends on how much you salt the water. For cooking starches it would be minimal, as you do not want to make the water saturated with salt, but there are recipies for cooking potatoes in water that is saturated because it is quicker and leaves a thin skin of salt on them.

 

[NeilC]

Why would a low concentration of salt in water get rid of starch? What do you mean get rid of? Where does it go?

 

[kmortis]

Alton also had a individual on his salt show claiming that for 90% of the population with out sodium related hypertension, that excess salt is not much of a problem

And if you drink lots o' water, that'll help retain the proper balance.

That all depends on how much you salt the water. For cooking starches it would be minimal, as you do not want to make the water saturated with salt, but there are recipies for cooking potatoes in water that is saturated because it is quicker and leaves a thin skin of salt on them.

Right, the so-called "salt potatoes" that are popular around these parts. Although, I've tried them and they were suprizingly bland.

Splossy,
I'm sure why the salt "gets rid of" the starch, but it has been my experience that I'll have less mealy potatoes with salt than without (assuming I use the same kinds of potatoes in moth batches). The starch just leeches out into the cooking water, which you then pour down the drain.

 

[nimzov]

NO!! you have to add LOTS of salt to raise the temp just a little.

Thanks but I had corrected my post with this one.

I agree that adding a bit of salt won't change much the boiling point of water. I think you have to add about 25 grams of salt to one liter of water to raise the boiling temperature to 106.

That is quite a large amount of salt in cooking.

nimzo

nimzo

 

[NeilC]

I'm not convinced by that starch thing given the concentrations of salt involved and the fact that my personal experience is that it makes no difference.

But the beans thing does interest me. Everyone says it hardens the skins. I'd like to know the chemistry behind this.