Ascorbic Acid - Powder vs Crystals

fingerpig

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Hi All

Assuming the l-Ascorbic Acid powder I bought (health product labelled as Vitamin C) is just that i.e. no extra ingredients...

Is this the same weight for weight as l_Ascorbic Acid in crystal form?

The reason I ask is that I am getting some very low activity from my FX55 brew (up to two stops speed loss) and having checked all that I can (incl PH of the final soup which is circa 8.2) I ordered some fresh l-ascorbic acid from Silverprint - besides it being expensive - it is in crystal form.

I've had a search and cant find any reference to any differences between power and crystal and also cant see anywhere where one form or the other is specified.

Can anybody clarify the differences (if any) between l-ascorbic acid in powder and crystal forms and any factoring of weights when interchanging one for the other?

Merry Xmas all and thanks for all the knowledge contained here in these forums.

Cheerz
Mark
 

Gerald C Koch

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The physical form whether powder or crystals would have no effect on its use. However products sold in health stores may not be pure ascorbic acid. Are you weighing out the chemical or just measuring a volume as is sometimes done. In this case the physical form would matter. In the US pure ascorbic acid would be labeled as USP grade. Is there a British equivalent? What does the label say exactly.

The formula for FX-55 is proprietary and never published so I have no reference as to what the pH should be. The pH of most of the Crawley formulas is available.
 
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Anon Ymous

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Crawley released the formula for FX-55 to the public domain back in 2008. It was never proprietary.
 
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fingerpig

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Thx Gerald
I'll have to check the label closely for the detail.
I measure my chemicals by weight not by volume. Is it therefore safe to assume that a specified weight of ascorbic acid can be either powder (assuming it is pure) or crystal?
Cheerz
Mark
 

Zathras

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I have used the Vitamin C crystals from Trader Joe's with good results in Pat Gainer's formulas. It sells for $11.99 per pound and claims that it is 100% pure Ascorbic Acid.
 

Gerald C Koch

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fingerpig said:
Thx Gerald
I'll have to check the label closely for the detail.
I measure my chemicals by weight not by volume. Is it therefore safe to assume that a specified weight of ascorbic acid can be either powder (assuming it is pure) or crystal?
Cheerz
Mark
Click to expand...

YES

There is also isoascorbic acid (also known as erythorbic acid) that actually is a bit more active as a developer. It is used extensively for food preservation.
 

Gerald C Koch

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Anon Ymous said:
Crawley released the formula for FX-55 to the public domain back in 2008. It was never proprietary.
Click to expand...

Sorry, I was thinking of Paterson FX-50. The formula was never released by Crawley. I understand that FX-55 may be similar to FX-50 but not the same.
 

Mick Fagan

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I purchase this locally from a cheap Chemist shop chain. There are two types of this packaging in this country, but the contents according to the writing on the exterior are identical. My usage with this tells me they are one and the same, 100% pure Ascorbic Acid.

For what it's worth, the suggested retail price of this product is $13.95 AUD. Online as in here, it sells for $11.85 plus shipping. I am fortunate enough to be able to bicycle down to my local cheap chemist shop and purchase this for $6.99 AUD.

I believe the Melrose brand of Ascorbic Acid is sourced from the USA, but I cannot be sure of that.

https://www.vitaminking.com.au/vita...UrQuy0qsAmdXqo88LGB1gWoHwReFIc7JhRhoC50Hw_wcB

The version on that packet, which I am currently using, says: Ascorbic Acid, Crystalline Powder.

The version on another packet with slightly different pictures on the outside and from the same company, but generally sold through different chemist and health food places to the cheaper chain, just states, "Vitamin C 100% pure Ascorbic Acid powder.

Mick.
 

Gerald C Koch

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A few years ago a poster wanted to know why his Vitamin C powder was pink and did not completely dissolve. Finally when he was asked to carefully read the label it was found that besides ascorbic acid it also contained powdered rose hips. Worthless for photography be he need not fear contracting scurvy. Always read the label.
 

Pixophrenic

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Hi, somewhat odd to reply after all these years, but I think that your problem was that the FX-55 recipe calls for sodium salt of ascorbic acid, which is slightly alkaline unlike pure ascorbic acid, so your final solution had a pH too low for the developer to work. If you use ascorbic acid, and omit the bicarbonate and bisulfite from the recipe, you get a developer that is relatively active (7-8 min at 23 C) but it only keeps for about a day.
 

removed account4

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hi mark

i get my vit c powder from trader joe's,
it works great and is relatively inexpensive ( without buying 50lbs ).
i've been using this vit c for about 11 years to make caffenol C ...

good luck!
john
 
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