Re: casein

Hello Judy,

Judy Seigel wrote:

>David, I haven't done casein but am determined to at least mix some and
>print a test strip for this issue (and having said that in public, hope I
>will...). I've got Lukas Werth's instructions from P-F, and as soon as the
>snow, hail and howling wind stop will go to Kremer for some of their
>casein... I also bought some dry milk for another approach... but I wonder
>if you would share your method for making casein? Where did you get your
>instructions?
>

I tried a few different recipes, some I found online and in books. This
is a hodge podged method I put together through my experiences.

Materials:
1 Cup Water
1/4 cup Powdered Milk
28 % Acetic Acid (or Vinegar or Lemon Juice)
Ammonia
Cheese Cloth (or a stocking as I prefer)

Make the water hot, almost boiling works well for me (I use a microwave)
then mix in the powdered milk. Most instructions say to use a few drops
of Acetic acid, then you mix it for what feels like forever (to me) and
eventually the milk curdles and you get the casein. Now you can call me
lazy, but what I do from here is I put about 15 ml of acetic acid (or
1/4 cup of vinegar) into a measuring cup and then pour the milk mixture
into it. This curdles it immediately and a few swirls of the cup and
you've got instant curds and whey. Some of the curds are small so I use
a stocking to filter them from the whey but you can also use cheese
cloth as well. Rinse the curds for a few minutes until they no longer
smell acidic. Fold over the stocking/cheesecloth and squeeze all the
water from the curds. If you're like me you'll stand there and play
with the curd for a while and comment to yourself how bizarre it feels.
Then crumble the curds into the bottom of a jar and pour enough ammonia
to cover them completely. Put a lid on the jar and shake it up.

If you like casein you can play with the amount of ammonia. The way I
described it will give you a fairly thick colloid, slightly thicker than
gum.

As ammonia looses it's strength once it's opened I've found that fresh
ammonia will dissolve the curd in 8 hours or less. After a few weeks
you may need to leave it for 24 hours or more before it dissolves
completely. You can't imagine how happy I was when I found a local
store selling ammonia in small 16 oz bottles. I was having to buy half
gallons before this. Now it seems like I always have fresh ammonia.

I'm not sure what the shelf life of casein is, but I've used it for as
long as two weeks without any variations. BTW: Casein hardens into a
gelatin looking slime if it's stored in a fairly cool place. Hold it
under warm water for a few second and shake it up to liquefy it again.
This confused me the first time it happened as I thought I hadn't added
enough ammonia. I had actually just left it in a window sill the night
a cold front moved in..lol

For developing, I float the print face down for about ten minutes in a
tray of room temperature water. Then I move it to another tray of
slightly warm water for ten more minutes. If the print is fairly dense
sometimes another 10 minute soak might be necessary. I've heard
recommendations of adding ammonia to the water for developing. This
speeds up development, but I find it easier to control by just using
warmer water. Ammonia can also be used if the print is slightly
overexposed, and not developing easy. It can "save" the print but the
prints I've had to do this with always look flat and lack contrast and
not worth saving anyway.

Hope my babbling is at least somewhat comprehensible. I really need to
subscribe to P-F, are back issues still available?

-David-
Received on Mon Feb 9 21:19:48 2004