Soaking Potatoes And Rice To Remove Starch?

[aliciahere]

This is something that I have heard for years. My mom taught me that you soak potatoes in water after you cut them and let them sit for up to 12 hours. After soaking you drain the water and the starch, if you cook the potatoes in the water they were soaking in it would cook the starch back into the potatoes. She advised me that soaking will remove most of the starch and will let the potatoes cook better (crisper).

I also found this when searching on how to cook the perfect sushi rice. That you should first rinse (several times), and then soak the rice to remove a majority of the starch.

I don't know if this is true, I tried to find more information on the interwebs but I can't find anything other than antidotal info. I also tried to search here to see if this question had been addressed already, and couldn't find any info here either....

So here I leave it - anybody have any idea if this is true? Any studies done on it? I know that with both foods they do taste and cook up better if they are soaked prior to cooking.

 

[Derek]

The sushi rice I have says to rinse until water is clear and soak 30 minutes, but the long grain white rice I have (of the same brand) says to just cook. No rinsing or soaking. So I don't know if it has anything to do with removing starch. I'd say just eat potatoes and rice and don't worry about having to remove starch. Seems like a lot of hassle/work for nothing IMO.

 

[tara]

Potatoes are mostly water, starch, and fibre. Soaking to remove starch would probably reduce the minerals and ketoacids too. I don't see any nutritional benefit, but maybe some textural difference, if that is important to you. My guess is it's the same with the rice - won't change the nutrition, might change the texture slightly.

If you are experimenting with leaving out starch, soaking isn't going to get rid of most of it. If you can manage the starch OK, why bother with such a procedure?

 

[James IV]

Soaking just about anything in salt water will make it easier to digest. Soaking starches in salt water will remove some of the amylose. I dont belie nutrient removal is a concern, since soaking them will allow for more complete digestion, so you'll probably break even.

If you have poor digestion, soaking starches may be a good thing to experiment with.

 

[onioneyedox]

Isn't rinsing meant to just remove starch from the surfaces. In case of rice the milling (or whatever) dust so that end product is fluffy and grains stay somewhat separate. And potato water doesn't wroth which makes boiling easier (though just good rinse is enough after peeling for that, no 12h soaking needed. Maybe the tip is just that you can peel them 12h in advance if needed)

 

[Westside PUFAs]

Saying you will remove the starch from a potato by soaking it is like saying you are going to remove the protein from a steak by soaking it. Picture a piece of steak or fish. It's not that steak or fish has protein, it is protein. It's a lump of pure protein. It's not that a potato has starch, it is starch. A steak has fat within the muscle which is the white part but it is very little. Within that is also some vitamins and minerals. The rest is protein. Groud beef has more fat because they grind the protein and mix in added fat. That is different than a piece of un-grinded meat which is mostly lean. When you peel the skin off a potato you have a ball of pure white starch. Within that ball of pure white starch are some pectins, fiber, vitamins and minerals, keto acids, and unstudied/undiscovered phytonutrients. Some potatoes such as new potatoes have more sugar and less starch but all roots or tubers have starch. Storing sunlight as starch is their basic function. During baking or steaming, the starch molecules absorb the surrounding moisture and swell and separate. This process of starch-grain bonding is called gelatinization, and can differ in potato varieties. The starch goes through three structural changes. It swells by absorbing water and increases its volume, the crystalline structure melts, and the granule is disrupted releasing the amylose. We humans then have a lot of amylase sitting in our mouths, in our spit, ready to start digesting the starch. The only way to remove the starch from the potato would be to run it through a centrifugal juicer. You are then left with the water of the potato and within that is going to be various micronutrients. But even still there will be a small amount of starch in the juiced water. It would take fancy lab equipment and knowledge of how to remove all of the starch from the juice. Just like it would take fancy lab equipment to remove all of the fat from unprocessed milk. Even if it is allowed to settle and rise to the top and skimmed, there is still some fat within the rest of the milk. But remember when you juice the potato and remove the starch you are removing the carbohydrate content so you have to get carbohydrate from somewhere else.

 

[jyb]

post 110323 Soaking just about anything in salt water will make it easier to digest. Soaking starches in salt water will remove some of the amylose. I dont belie nutrient removal is a concern, since soaking them will allow for more complete digestion, so you'll probably break even.

If you have poor digestion, soaking starches may be a good thing to experiment with.

Potato and some other vegetable can lose most minerals like potassium in water. I drink the cooking water and throw out most of the potatoes.

 

[James IV]

post 110323 Soaking just about anything in salt water will make it easier to digest. Soaking starches in salt water will remove some of the amylose. I dont belie nutrient removal is a concern, since soaking them will allow for more complete digestion, so you'll probably break even.

If you have poor digestion, soaking starches may be a good thing to experiment with.

Potato and some other vegetable can lose most minerals like potassium in water. I drink the cooking water and throw out most of the potatoes.

I was referring to soaking the potatoes. Which results in insignificant mineral loss. Boiling them is another story.

I suppose the question is what is one's reason for costuming the potatoes.

 

[tara]

Westside, I agree with most of what you said, but since I too have a habit of pedantry -

post 110397 all roots or tubers have starch

Not all roots have much if any starch. For instance, turnips (at least some kinds), radishes and carrots have little or none.

post 110455 I suppose the question is what is one's reason for consuming the potatoes.

Indeed.

 

[Westside PUFAs]

post 110458 Not all roots have much if any starch. For instance, turnips (at least some kinds), radishes and carrots have little or none.

Composition data of various foods is extremely lacking like when Peat talks about his attempts to test the protein in fruits. The ~ symbol seen on databases means it wasn't tested for that chemical. Some tubers have more sugar like beets and sweet potatoes but it depends on the variety. Carrots don't have much starch, they have some but they are related to parsnips which have lots of starch and they look just like carrots just a different color:

There are also non-tubers, above-ground plants that have starch like squash and grains. But it seems like non-commercial food may be a different story as in these very large turnips:

 

[tara]

post 110461 Composition data of various foods is extremely lacking like when Peat talks about his attempts to test the protein in fruits.

Yes. I don't necessarily expect nutritiondata etc to be very precise. Also, the mineral and carbohydrate content at least, and maybe protein too, can vary a lot, depending on growing conditions and what's in the soil and maturity/ripeness.

post 110461 Composition data of various foods is extremely lacking like when Peat talks about his attempts to test the protein in fruits. The ~ symbol seen on databases means it wasn't tested for that chemical.

I understand that ~ means not measured. But if the total carbs are measured, and fibre and sugar quantities are listed and add up to the total carbs, I deduce that the starch content is negligible. Not necessarily 0, but close. I think that applies to the ones I mentioned.

post 110461 Carrots don't have much starch, they have some but they are related to parsnips which have lots of starch and they look just like carrots just a different color:

Parsnips are common fare around here. Indeed they are similar in shape, and both umbrelliferae. They are very different in taste and texture to carrots, though, and as you say, more starchy. I don't know if any of the umbrelliferae roots other than carrots have fibre that can be eaten raw to similar effect as carrots. No one round here eats parsnips raw - they are generally roasted. I think humans mostly eat the above ground portions of the other edible ones. Not going to experiment with hemlock. :)

 

[aliciahere]

Wow, this received a lot more attention than what I was expecting - thanks for the replies.

Yes

post 110365 Isn't rinsing meant to just remove starch from the surfaces. In case of rice the milling (or whatever) dust so that end product is fluffy and grains stay somewhat separate. And potato water doesn't wroth which makes boiling easier (though just good rinse is enough after peeling for that, no 12h soaking needed. Maybe the tip is just that you can peel them 12h in advance if needed)

Yeah, one of the benefits that my Mom explained was that you could cut the potatoes early, soak them till supper and they wouldn't brown - she advised me it was twofold. Looking into it a bit more, yes, I think it does just remove the starch from the surface.


I don't appear to have an issue digesting starch, my tummy likes potatoes and rice - nice warm feelings in my belly after eating :)

Thanks for the input everybody!

 

[Luna]

There is a benefit to soaking.

Soaking raw potato slices in water for 15 to 30 minutes before frying or roasting helps reduce acrylamide formation during cooking. (Soaked potatoes should be drained and blotted dry before cooking to prevent splattering or fires.) Acrylamide