Artwork-Miya Arts Gouache over Jack Richeson Artist Casein on Hahnemühle Cézanne Cold Press. Brushes: Jack Richeson 713995 Watermedia Pocket Plein Air Brush Set Photo reference from Skeeze on Pixabay.
So how did I get from this to that? And what’s this Casein thing? Aren’t I all about the gouache these days?
The story starts long ago. We’ve found recipes for Casein adhesive, a homemade curd made from soured skim milk from the 11th century, though we suspect the Egyptians were using it well before that.
The Persians used gouache as early as the 9th century. Like watercolor it is natural pigment bound with gum arabic. The main difference between the two comes in the way each is made.
Up until acrylic paint became available, these Casein and Gouache were the choice for professional illustrators because they are quick to dry and their matte surfaces are easily reproduced.
Obviously, I wasn’t around for all of this – I’m old but not that old. Casein is hard to find, and it has a strange smell. Whereas Gouache can be rewet and easily reactivated, Casein will eventually become harder to reactivate – requiring a mix of ammonia and water.
So why even try it? Many illustrators still use it as an undercoat for watercolor, gouache, acrylics and oils. You can prep your paper with any color, and then paint over it later. You know me – I have to try these things. I HAVE to! It’s a thing.
I just bought one color – Raw Sienna and painted my mushrooms with gouache. I’ll try watercolor next.
The smell isn’t too bad, but I doubt I’ll use a lot of casein unless I do want to prep a surface. I may pick up a color that is good for the sky, too. Eventually.
Life Imitates Doodles 
These mushrooms are so beautiful, so nice!
Thank you, shaninge!
I love those ‘shrooms! And thank you for discussing casein and gouache. I’ve seen paintings done with the former wth great results, too, but I don’t think I would get past the “smell.” 😀 Meanwhile, I’ll be working in some gouache studies with the primaries I still have before investing in the fun colors, like Holbein Opera and Lilac.
Thank you, Kathy. I don’t think it will be long before I invest in a set of professional gouache – though I might buy a tube or two of fun colors first, just to see if they really are that much different from my ‘kids’ set.
You’ve piqued my interest about casein. If it’s used as an undercoat – have you tried doing twin paintings, one with casein and one without?
I haven’t done that yet, though it’s on the list of experiments to try. I’ve got some travel and heavy-duty family stuff coming up soon, so my experiments will end in a few days and not start up again for a couple of weeks. I’m kind of sad about that, because I’m having lots of fun!