Colour Change

[pastafreak]

Why does my water soluble supplement...magnesium Glycinate...turn my normally red Robinsons-type squash blue?

[minesapint]

It might be useful if you could provide further details oy your red Robinson-type squash. Is it made by Robinsons? What is it called? If not, let's have the manufacturers name and the name of the product. without this information, we are all working in the dark.

You really need to be more specific pastafreak if you want a definitive answer.

[Old_Geezer]

Because it's upset that you used a supplement.

[pastafreak]

For minesapint...this is what I've used.

http://www.sainsburys.co.uk/shop/gb/groceries/squash/robinsons-squash-summer-fruits-66ml

[gingejbee]

The "squash concentrate" contains natural coloring and acidity regulators....so I'm assuming that at the correct pH the liquid is red. Your supplement is changing the pH....so it's acting like a pH indicator (like litmus, for example).

[pastafreak]

Thank you dive buddy and gingejbee for answers that make sense. I assume the effectiveness of the supplement is not changed.
One thing that is odd is that this did not happen when I first used the powder a few weeks ago. Could water supply have anything to do with it?

[pastafreak]

That's interesting. I may buy some bottled water...and see if that makes a difference. The blue colour is off-putting to say the least.

[theprof]

Good effort folks but the answer is a little more complicated.

This Robinsons squash is acidic due to the addition of sodium citrate, a common practice amongst squash manufacturers nowadays for reasons I won't go into here.

The anthocyanins in the squash are a shade of red in colour as long as the squash has a pH below 7 (i.e. acidic). However, magnesium glycinate is a chelated and consequently buffered compound that will raise the pH into the neutral (pH 7) or slightly alkaline pH (pH 7.5) despite the parent compound, Glycine, being an amino acid. Most anthocyanins are blue or purple at pH 7 or above. This is what caused the change in colour.

It's totally harmless pastafreak and you can safely drink it even though the colour may be off-putting. By and large, the water source in the UK will not change anything but I won't exclude it entirely.

[theprof]

I'm grateful you concur divebuddy. However, I'm afraid I was not saying the same thing as closer examination of my post will reveal.

Having been a member of The Answerbank for many years, I post here on the basis of never underestimating the intelligence of a forum member. I post comprehensive answers that can be appreciated by some but less so by others. This way, the reader is either able to take in the answer or skip it if it goes over the top of his or her head. Laconic answers only serve to create more confusion for some people.

The Answerbank has never been a "one size fits all" forum as far as answers are concerned. If you consider my answers wordy on this basis, opinion on here would seem to point to the contrary.

[theprof]

The Answerbank members have a thirst for knowledge. I won't ridicule them by dumbing down my answers.