Fructose Powder

Fructose (fruit sugar) is the reducing agent in the popular 1-2-3 fructose indigo vat, developed by master dyer Michel Garcia. In an alkaline bath with lime, fructose removes oxygen from the indigo so it can dissolve and dye fiber. It is a simple, natural and long-lasting alternative to chemical reducers.

Sizes: 50 g (1.76 oz) and 400 g. Use with our natural indigo extract.

The 1-2-3 recipe

By weight: 1 part indigo : 2 parts slaked lime (calcium hydroxide) : 3 parts fructose.

• Light blues: about 2 g indigo per liter of vat
• Medium blues: 3–5 g per liter
• Dark navy: 7–10 g per liter

Example for a medium 3-liter vat: 10 g indigo, 20 g lime and 30 g fructose.

How to make a fructose indigo vat

1. Fill a lidded stainless steel or plastic container with hot water (about 50 °C / 120 °F).
2. Stir in the fructose until dissolved.
3. Mix the indigo into a smooth paste with a little warm water and add it to the vat.
4. Sprinkle in the lime and stir gently in a circle, without splashing.
5. Cover and leave for about an hour, until the liquid under the surface turns clear yellow-green and a coppery "flower" forms on top. Vats often work even better after a day or two.
6. Dye at 30–40 °C (85–105 °F): lower wet fiber in gently, wait a few minutes, lift out and let it oxidize to blue in the air. Repeat for darker shades.

Keeping the vat healthy

• pH about 9–10 for wool and silk, 11–12 for cotton and linen.
• If the vat turns blue or stops dyeing, add a spoonful of fructose and a spoonful of lime, stir gently and let it rest warm.
• Use real fructose, not table sugar, and fresh lime: old lime that has absorbed air will not work.
• Never stir up the sediment while dyeing, and do several short dips rather than one long one.

Learn more: Indigo vat guide with 3 blue shades · Shop natural indigo

Frequently asked questions

Why use fructose for an indigo vat?

Fructose is a natural reducing agent. With lime it removes oxygen from indigo so it dissolves and can dye fiber, without harsh chemical reducers.

Can I use table sugar instead of fructose?

No. Table sugar (sucrose) does not reduce indigo well. Use fructose.

How much fructose do I need?

Three times the weight of your indigo. For 10 g of indigo, use 30 g of fructose and 20 g of lime.

Work out exact grams for your fabric with our free natural dye calculator and WOF chart.