Lye from Ash

These jars contain wood ash from various sources and are being tested for alkalinity. High alkaline ash water is the base for a traditional Japanese fermentation vat. No matter where you are or what kind of indigo you are using, a high alkaline, oxygen free atmosphere is essential. These conditions can be met in various natural or synthetic chemical ways and they all have their advocates. I like the natural fermentation way for several reasons and one of them is I have access to good quality ash left after potter friends fire their kilns. I couldn't reason burning down a specific kind of tree just for my dye pot so even though it is not the traditionally preferred kind it is doing it's job well.

It is the fermentation in a fermentation vat that causes the loss of oxygen(reduction). The high alkali from the wood ash dissolves the normally insoluble indigo making it lose an oxygen molecule. In this state it is colorless and called 'indigo white'. When you lower what you want to dye into the vat the indigo attaches itself to the fibers and when you lift it out oxygen from the air re-attaches itself to the indigo, oxidizing it, which causes the fabric to turn blue right before your very eyes. It can make you feel a little like an alchemist, or a witch, and this is when, if you are going to get bit by the bug, you will.

I make my ash water by putting the ash into a bucket, filling it up with hot water and stirring it everyday for a week. The ph level varies according to the type of wood and how it was burned and apparently other things. The highest ph level I ever got from wood ash was 13. I am working now with 10.8 but my 40 liter vat is maintaining at 11.4 and doing great.

I heard at one point that bacteria in the ash aids the fermentation process but I have never read that anywhere. I have read that the bacteria in the dye root madder, added to some vats in India, does help.