My first home made casein emulsion

MichaelFraley · #1 04-19-2011, 01:45 AM

I made a skim milk / tonic water casein emulsion today, and it works extremely well, handling just like Shiva emulsion, but without the ammonia smell.

Granted, anything like this will have a limited shelf (or refrigerator) life, but other than that, do the casein emulsions made with ammonia or borax have advantages that my simple little science experiment doesn't?

Thanks,

Michael

dbclemons · #2 04-19-2011, 08:22 AM

Exactly how did you make the medium, Michael? If you don't use an alkali of some sort, like lime, ammonia, or borax, then the casein isn't converted into a glue.

MichaelFraley · #3 04-19-2011, 12:05 PM

Thanks for responding, David.

I combined the skim milk and the tonic water, which immediately began to curdle, thanks, I think, to the quinine content of the water. I got the idea from the "CSO" web site.

I mashed the curds into a fine paste, combined a little vinegar as a preservative.

I then prepared my pigment by mixing it with water, then adding a bit of my paste.

Other than needing to wait, I think, for the curd to break down a bit further, I'm having good results from the paint. It does't brush away when dry.

dbclemons · #4 04-19-2011, 12:42 PM

Oh, sorry, I overlooked the "tonic" part of your original post. Yes, quinine is an alkali. I'm not sure how effective it is in comparison to the others. It's probably more expensive to produce. It is best to let time do it's thing and cause the casein to gel properly before using.

MichaelFraley · #5 04-19-2011, 02:41 PM

You're undoubtedly right. Thanks for your help.

dbclemons · #6 04-19-2011, 05:53 PM

You might also want to take a close look at the ingredients of the tonic water. If it has anything other than diluted quinine then you're adding something to the paint that it doesn't need, possibly flavorings and sweetners. I've never tried quinine so it would be interesting to make comparisons if it can be acquired in raw form easily.

MichaelFraley · #7 04-19-2011, 06:28 PM

It appears to have sugar and some preservatives. Well, nuts. I hope the sugar doesn't damage things for me in the long run. Yes, tonic water is easily available and at roughly $1 a liter, it seemed to be an experiment worth trying.

The curds are continuing to break down, so it doesn't quite resemble cottage cheese anymore. Trusting that this is a good sign.

dbclemons · #8 04-20-2011, 08:37 AM

Don't sweat over it too much. If it's corn syrup, that's sometimes used in watercolors, as is honey. It's just better when making paint to have control over what exactly is being used with only the things you need.

Quinine is used to help relieve muscle cramps and pains so you might find some at a health food store or pharmacy, but anything edible is likely mixed with other things to make it taste better. Borax, on the other hand, is very easy to get in raw form at a grocery store laundry section, at least for me.

MichaelFraley · #9 04-20-2011, 09:57 PM

David, I've looked for borax (hmm, sounds like an old Space Ghost villain) at the grocery store, but all I've found is the box of stuff with the little old fashioned looking cowgirl on the front. "20 Mule Team" or what have you. Can that possibly be it? As for the sweetener in the tonic water - I'm pretty sure it's corn syrup, since corn syrup is practically in the air we breathe these days ... I used to drink tonic water to help with leg cramps, but it never seemed to do any good, and it was so bitter that I would never have guessed that it had any sweetener at all in it.

dbclemons · #10 04-21-2011, 08:46 AM

"20 Mule Team" is a brand name. It's has traces of other minerals but is still pure borax and okay to use. You can get more refined borax online.

I've also read of people using baking soda but I could never get that to work.

MichaelFraley · #11 04-25-2011, 04:30 PM

Just an update. At this point I've warmed the curds from the skim milk (about 3/4 cup, if packed) with a little cold water and a few tablespoons of borax in a double boiler. So far, most of the curds have dissolved, and I'll eventually fish the remainders out. While the resulting syrup isn't completely cool, it does seem a little thinner than I would have imagined. I added perhaps 1/3 cup of water, but I now have probably over a cup of syrup or glue.

I imagine that when I mix the glue with my pigments, I shouldn't add any water to the mixture. I think that would be just too much.

I'm not at the end of this experiment yet, but I'm still grateful for all of the help.

= Michael

dbclemons · #12 04-25-2011, 08:25 PM

Michael, there's no need for a doubleboiler or constant heat. It sounds to me like your using more water and borax than necessary, which will make your binder more alkaline than it needs to be.

To precipitate the milk into casein curds, I use a little vinegar over heat for a few minutes, about 1:4 vinegar to milk, and then wash the casein well to remove as much excess vinegar as possible.

For 3/4 cup of casein I wouldn't recommend heating more than about 2 ounces of water to near boiling and dissolve in it @ 2 teaspoons of borax. Mix the borax solution in the casein and just let it sit for a few hours at room temperature stirring it occasionally to let the hydrolysis do it's thing and turn the casein into a gel. I keep the container covered so the water doesn't evaporate. You shouldn't have any casein "remainders". You can always dilute the casein later with water if necessary, bit I wouldn't want to start with it too thin.

MichaelFraley · #13 04-25-2011, 09:45 PM

Thanks David. Most of the recipes I found online suggested a double boiler, and I use one for RSG anyway. I warmed the main boiler with some water in it, then placed my jar of curds in it, being careful not to bring it to a boil.

I probably did add a little too much water to the curds, but from what you're describing, I added perhaps another ounce more than you've suggested. The borax ... I probably did add a little too much, but we'll see how it works. I'm just enjoying the process, and will not cry too many tears if it's not completely successful.

= M

MichaelFraley · #14 04-25-2011, 11:51 PM

Did some paint tests tonight on Lenox 100 paper, and so far so good! Not creamy at all, but decent coverage and opacity for being a thin syrup and all. Seems closer to being an ink, really ... No brush-offs of pigment yet, but I'll give that a bit of time.

MichaelFraley · #15 04-30-2011, 08:07 PM

Well, my first try at producing a syrup or glue was all right, even though it was a bit thin. I have no complaints, really. I just know what I'll do next time ... which will probably be tomorrow.

Over the past few days I've also been experimenting with producing a soy-based casein, and have had some good results. I know that there is a Japanese tradition of making dyes with soy milk and pigments - and on paper it works as a nice sort of watercolour. When you curdle the soy milk (the first step in making tofu), the borax doesn't seem to dissolve the curd quite as well, but you end up with a substance which is the consistency of sour cream, and is very nice to paint with. However, I don't know how strong or how stable a soy-based casein paint is, so I'm going back to a regular milk casein base for now. In the west, it's had a long, documented history and a proven track record. I've not been able to uncover a great deal about the strength of soy caseins.

= M

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