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  1. #1

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    Vitamin C strength

    I just ran out of the NOW Foods Vitamin C I've using ever since I started making my own developer last year. The replacement is of The Vitamin Shoppe's house brand, which is also supposed to be pure. It's a finer powder, which means it mixes faster, but I've noticed it's weaker than what I used before. I need 40% more by weight to make the film developer as active as with NOW Foods Vitamin C.

    What does this mean? Is the VS powder getting old, or is it just slightly oxidised from the start because it's a finer powder? Anyone else noticed differences between brands?

    I mix the vitamin in just before development, so there should be no issues of impurities that would cause instability in stored solutions.

  2. #2

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    It may be weaker. On the other hand, it may be calcium ascorbate or a mix of calcium and sodium ascorbate. Is it described as ascorbic acid or as an ascorbate?

    My personal choice is Trader Joe's 99% pure ascorbic acid (in the vitamins section).
    Tom Hoskinson
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  3. #3

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    It does say it's the acid form. This is it, C-1000:

    http://www.amazon.com/exec/obidos/AS...020749-8863260

  4. #4

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    Quote Originally Posted by psvensson
    It does say it's the acid form. This is it, C-1000:

    http://www.amazon.com/exec/obidos/AS...020749-8863260
    Interesting - and expensive! A pound of Trader Joe's 99% pure ascorbic acid powder is about $6.00.

    There may be a clue in the description of the C1000. "Ingredients
    Vitamin C: 1000mg." The total weight of the product is 17 ounces??
    Tom Hoskinson
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  5. #5

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    I can get ascorbic acid at my health food store for $16/lb; pricey, but convienient. Is Trader Joes an online outfit, or a retail chain or something completely different?

  6. #6
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    I just picked up some ascorbic acid tablets at my local Costco ... in house brand, 500 tablets of 500mg each for $9 (Canadian which is about $7US). Works fine for me ... complete with insoluble inert floaties

  7. #7

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    The C-1000 only cost $9 in the store - weird that it's so expensive online.

  8. #8
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    it means 1000 mg of VitC/serving, thus it has been diluted with some filler.

    PS. I'm using Erythorbic acid or D-ascorbic acid, which is an isomer of vitamin C that is used in meat curing and beverages as antioxidant, but it doesn;t have the "vitaminic" action of L-ascorbic acid. So far it exhibited the same properties as L-ascorbic acid for film processing.
    Mama took my APX away.....

  9. #9

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    Titrisol, they're saying its 1000mg of Vitamin C per 1/4 tsp, same as NOW Foods. That doesn't really leave space for filler. 1/4 tsp weighs 1g.

    I thought erythrobic acid was isoascorbic, i.e. an even mix of the enantiomers? Or are you using what's left over after they extracted the L-form?

  10. #10
    titrisol's Avatar
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    they are "optical" isomers, which means they are chemically the same but our bodies cannot metabolize erythorbic acid.
    isoascorbic = D-ascorbic

    It is used when companies do not want to claim "vitamin C" in their products, but want the anti-oxidant effect, such as in Ham and other meat products. I think it is a lot cheaper than Vit-C
    Mama took my APX away.....

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