Under-Reduced Fructose Vat

Q: I have been dyeing in a fructose vat and no matter how many times I rinse my pieces the water still runs blue. Am I doing something wrong?

A: My guess is that the indigo in your vat isn’t fully reduced. Fructose vats are often “under-reduced” which means that the color is more weakly adhered to the fabric and thus rinses out more. You can just add new reducing ingredients to your old vat contents so you don’t waste the indigo though you’ll begin to build up more sediment which makes the dyeing more challenging (as you’ll need to make sure your fabric doesn’t get that material on it).