Ascorbate question for Gainer

Discussion in 'B&W: Film, Paper, Chemistry' started by Maine-iac, Nov 22, 2004.

  1. Maine-iac

    Maine-iac Member

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    Pat,

    I noticed in one post that you mentioned that Health Food store Vitamin C is mostly calcium and has a precipitate problem. I haven't noticed that. Of course, I bought two large jars of Vitamin C powder (with rose hips!) about five years ago, and am still working away at them, so perhaps newer products are different. The only precipitate I notice is a settling out of the rose hips which I simply deal with by not emptying the gradutate completely into my tank.

    Is it really necessary to mix baking soda with the Vitamin C powder, or do different brands of Vitamin C powder available in health food stores contain different ingredients?

    Larry
     
  2. Jordan

    Jordan Member

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    Larry, I'm not Patrick but perhaps I can answer... You need to look carefully at the label, basically, and distinguish between Vitamin C itself (ascorbic acid) and its salts (sodium ascorbate, calcium ascorbate, etc.) They are not directly interchangeable in developers for obvious reasons.

    Most health-food stores sell the acid form of Vitamin C, like your Rose Hips preparation, but I've found (by reading the labels) that many of the Vitamin C supplements sold at these stores are actually in the form of calcium ascorbate, the calcium salt of vitamin C. These are usually marketed as neutralized Vitamin C or "Ester-C" or things like that.

    This use of calcium ascorbate is good for the body -- it should be less jarring to the stomach and also provides a source of calcium -- but no good for developers. As soon as you add this calcium ascorbate to a solution of alkali you will get a precipitate, various hydroxides of calcium (lime) or calcium carbonate (marble, chalk) etc.

    I did manage to find powdered Vitamin C at a store called the Vitamin Shoppe or something like that. It was a chain and they had a few stores in Boston so I presume you may find one in Maine too. They sold powdered pure Vitamin C (no rose hips) in 200-g bottles for a reasonable price. I've been using it in Gainer developers with good luck.
     
  3. Maine-iac

    Maine-iac Member

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    Thanks, Jordan for the clarification. In looking back at the original post, I see I was thinking "ascorbic acid" when the post was about ascorbate. Yes, it is the ascorbic acid I use rather than the ascorbate. At the time I bought it, I could only find it with the Rose Hips, so bought it and discovered that apart from the rose hips settling out at the bottom, it worked fine.
     
  4. dancqu

    dancqu Member

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    At www.leeners.com they have ascorbic acid for $19.95 a pound plus
    S&H. Is that a good price? Perhaps the local wine and beer homebrew
    outlets have smaller amounts at a good price. Dan
     
  5. Jordan

    Jordan Member

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    Dan, I'm not in the US anymore but when I lived there and was buying my ascorbic acid at the "Vitamin Shoppe" I seem to remember paying around $7 for about 175g. So your price is not out of line.

    I seem to remember Pat telling me about how he got some ridiculously large (for any of us -- not for him) quantity of some isomer of ascorbic acid for a relatively low price. Perhaps he'll see this thread and chime in.
     
  6. gainer

    gainer Subscriber

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    Yep, I saw it. Erythorbic acid is also known as isoascorbic acid, the same as in Xtol. It has the same empirical formula as the vitamin, but is a mirror image. Our bodies can tell the difference, but our films cannot. It is obtainable in various quantities from www.kicgroup.com. Of course, if you are getting small quantities, you can use up your savings in shipping costs, so check around.

    What I meant about calcium ascorbate was that it is the ascorbate salt most often found at health food stores. You can often get ascorbic acid, but sometimes a part of it is from rose hips, as you found. I suppose that gives it an extra aura of "nature" for the health nuts.
     
  7. titrisol

    titrisol Member

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    erythorbic acid has the same antioxidant qualities as ascrobid, but is not absorbed by our bodies because it is an isomer, yet it is used in some food products where vitamin claims are not necessary.

    It is produced in great quantities and used for apple sauces, some meat products, canned vegetables/fruits and some adhesives.

    Films will not know the difference, unless it's caught a cold :wink:

    ERYTHORBIC ACID:
    CAS # 000089-65-6
    Molecular Weight: 176.13
    Molecular Formula: C6H8O6
    Structutre: [​IMG]
     
  8. gainer

    gainer Subscriber

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    I should have mentioned that calcium ascorbate makes sense for human consumption because both calcium and vitamin C are needed for repair of connective tissue and bones. You get both in one bottle.