Can anyone supply answers to the following questions?

1) Is the compound 'potassium chloride' contained in organic tomatoes? (I was thinking 'no' but a raw food expert told me otherwise and I want to double-check.)

2) Could you supply a source for chloride levels of various plant foods (and let me know whether you have it to hand?)

Thanks in anticipation!

I know...not the sexiest of topics, is it? 20 have viewed and fallen asleep.

Debbie,

Potassium Chloride is used as a synthetic fertilizer compound, so it isn't typical in organic farming[David Zane Mason, interpolate your superior knowledge here]. The ubiquitousness of synthesized halites means there's probably drift, though in minuscule amounts. I doubt there have been exact data compiled on ratios found in common produce crops, but you could check the Environmental Working Group's website to see if there is a list. Good luck.

THanks, Tamukha. That's exactly why I thought it wouldn't be found in organic tomatoes, and didn't feel confident about what I'd been told. Good to know you feel similarly.

Yes, David, can you help here?

> 2) Could you supply a source for chloride levels
> of various plant foods...

Debbie,
Chloride is an essential 'trace' nutrient for plant growth. It is considered generally ubiquitous in nature. It looks like it's mostly taken for granted and "forgotten" when tracking mineral content of foods, but at least plant foods should have a trace amount. It's a bit frustrating that chloride tends to be lumped with the discussion of salt (sodium chloride) as minerals we get plenty of by salting our foods. This doesn't give much info to the no-salt group. But if animals can live without table salt so can we...

"Sixteen chemical elements are known to be important to a plant's growth and survival. The sixteen chemical elements are divided into two main groups: non-mineral and mineral." [www.agr.state.nc.us]

hope this helps



Edited 1 time(s). Last edit at 04/29/2009 01:53PM by loeve.

I agree, loeve.

It would be good to have those figures though.

> It would be good to have those figures though.

Debbie,
It's interesting that plants need only trace amounts of chloride, but animals need macro amounts. Maybe partly it's because animals need chloride to produce hydrochloric acid for digestion.

The British Nutrition Foundation notes a Reference Nutrient Intake of sodium of 1.6g/day in order to meet nutritional needs:

"The chemical name for salt is sodium chloride. Sodium makes up about 40% of salt by weight (chloride the other 60%)."

"On average discretionary salt has been estimated to account for around 15 to 20% of total sodium intake. Sodium naturally present in food accounts for about 15%, and salt added to food during manufacture or processing accounts for the difference i.e. 60 to 70% of total sodium intake.

"In the body sodium is required for the maintenance of extracellular fluid volume and hence blood pressure (BP), and for the generation and transmission of electrical impulses in nerves and muscles and the uptake of certain nutrients from the small intestine. Based on physiological requirements, the Reference Nutrient Intake for sodium is 1.6g per day (equivalent to 4.2g salt per day) and the Lower Reference Nutrient Intake for sodium is 0.58g per day (equivalent to 1.5g salt per day)."

"...Based on physiological requirements, the Reference Nutrient Intake for sodium is 1.6g per day (equivalent to 4.2g salt per day) and the Lower Reference Nutrient Intake for sodium is 0.58g per day (equivalent to 1.5g salt per day)."


[www.nutrition.org.uk]

..oddly it may be the cattle industry that has compiled more data on optimum added sodium chloride. Animals are often removed from their natural sources of minerals, eating purified food sadly from the confines of cages and out of bins, missing out on direct soil sources of essential minerals. Salt is added to animal feed at the rate of 3g/kilo of alfalfa and such other natural foods.

[www.ansi.okstate.edu]

..translated to the strict 'fruiter' and/or fresh veggie eater that's a little like adding 3g of table salt per kilo of produce!

..so exactly how much chloride is in plant foods? I'll try to get back on that...

again, hope this helps



Edited 2 time(s). Last edit at 04/30/2009 01:52PM by loeve.

> It would be good to have those figures though.

Debbie,
The chloride content of tomatoes is 108mg/cup (180g) [www.whfoods.com] (whfoods as an 'in-depth' nutrient content button!)

BTW, the sodium content of tomatoes is 16.2mg, calcium 9mg, and potassium 399.6mg -- all salts.

So the saltiness of tomatoes could be attributed to small but significant, IMO, amounts of chloride, sodium, and calcium, and lots of potassium; stated this way because plants uptake these minerals in their dissolved elemental state, and not as they may appear or have have been added to the soil (sodium chloride, potassium chloride). [genomebiology.com]

Edit: "Potassium may be detected by taste because it triggers three of the five types of taste sensations, according to concentration. Dilute solutions of potassium ion taste sweet (allowing moderate concentrations in milk and juices), while higher concentrations become increasingly bitter/alkaline, and finally also salty to the taste... [en.wikipedia.org]



Edited 1 time(s). Last edit at 05/01/2009 12:28PM by loeve.

Loeve,

Thank you so much for going to so much effort.

Already familiar with salt/sodium chloride (the compound) subject matter.

It's specifically potassium chloride (the compound) and chloride (not the compound :-)) I'm researching, and you've really helped.

I'm not sure potassium 'as such' would account for the salty taste, as there are lots of other foods (eg fruits) higher in potassium than tomatoes and they don't taste salty. Having said that, perhaps it's because the tomato is a non-sweet fruit.

I was really interested in the compound 'potassium chloride' rather than 'potassium', as 'potassium chloride' is sometimes used as a salt 'substitute' for those on low-sodium diets, and that's why I felt 'potassium chloride' could be accounting for the salty taste. But then 'potassium chloride'is usually part of artificial fertilisers, so only non-organic tomatoes would be affected.

Anyhow, I'd like to thank you enormously for supplying these figures:

'The chloride content of tomatoes is 108mg/cup (180g) [www.whfoods.com] (whfoods as an 'in-depth' nutrient content button!)'

I'd actually found it ridiculously hard to obtain figures for chloride in mg - USDA doesn't include it in the nutrients list.

So, excellent, Loeve! And many thanks for taking the time.

Cool, I'm also interested in potassium chloride (KCl), the compound, having used it myself and being curious from plant biology and human health perspectives.

My understanding is that KCl freely dissolves in water, so KCl added to soil as fertilizer would be dissolved by rain into K+ and Cl-, and that plants would then uptake the K+ and Cl- independently via metabolic transporters according to its needs. [www.jbc.org]

As an example of how potassium and chloride are found in nature, sea water contains salt ions; chloride, sodium, magnesium, calcium and potassium:

Total Molal Composition of Seawater (Salinity = 35)[5] Component Concentration (mol/kg)
H2O 53.6
Cl- 0.546
Na+ 0.469
Mg2+ 0.0528
SO42- 0.0282
Ca2+ 0.0103
K+ 0.0102
[en.wikipedia.org]

..in sea water solution they occur in the stable ionic form (plus or minus an electron), and not as common salt (NaCl) or potassium chloride unless as part of ancient dryed salt ocean deposites, or refined by manufacturing.

Adding KCl to soil as fertilizer is mainly a way to get potassium, which is highly reactive (even explosive) alone as K, packaged and delivered to the soil (with Chloride taging along as a cheap stabilizer), again then freely dissolving into K+ and Cl- which are the stable bioavailable forms selectively absorbable by plant roots.



Edited 2 time(s). Last edit at 05/02/2009 02:39PM by loeve.

Hmm....so if it simply dissolves into potassium and chloride ions then that blows my theory re potassium chloride accounting for the salty taste in non-organic tomatoes :-) (perhaps I'll go back to the other hypothesis, which was high 'glutamates').

Debbie,
I'm not 100% confident with this chemistry stuff, but the KCl theory for the saltiness of tomatoes may be directly or indirectly true in that the levels of potassium and chloride are significant even though they may be in the dissolved ion forms (K+ and Cl-), the taste effect being that of KCl, IMO. So lets see, if there's 108mg chloride/cup of tomato then that's enough to simulate about 270mg of KCl (KCl is 60% potassium by weight). Plus there's 237mg of N+ salt beyond what might conceivably be paired with Cl-.

Between the savory glutamates and subtle salts in non-sweet tomatoes I like your theory a lot.

That's good (as it might be seen in print soon, ie published...)