Mordant/Indigo - Fructose

Fructose Crystalline is a natural reducing agent used in the preparation of sustainable indigo vats. Made from 100% pure crystalline fruit sugar, it offers a gentle, eco-friendly alternative to synthetic reducers such as sodium hydrosulphite, allowing indigo to be reduced and used without harsh chemicals.

In an indigo vat, fructose works by gradually consuming oxygen, enabling the indigo pigment to convert into its soluble “leuco” form. This process creates a stable, easy-to-manage vat that produces rich, lasting blues without releasing harmful by-products. Fructose is widely used in so-called “1-2-3 vats” (one part indigo, two parts lime, three parts fructose), which are known for being reliable, low-odour, and straightforward to maintain. It performs consistently with both natural indigo and woad, and is suitable for dyeing a wide range of fibres including wool, silk, cotton and linen.

Favoured by both beginners and experienced dyers, fructose vats offer a controlled, sustainable approach to indigo dyeing, making them ideal for home studios, workshops and educational settings.

Benefits

• Natural, non-toxic alternative to synthetic reducing agents
• Creates stable, easy-to-control indigo vats
• Supports long-lasting vats with minimal maintenance
• Odourless and suitable for indoor use
• Produces strong, vibrant blue tones without chemical runoff

Perfect For

• Natural indigo or woad dye vats
• Eco-textile and sustainable fashion studios
• Educational workshops and home dyeing setups
• Traditional indigo dyeing and craft production

Technical

• 100% pure crystalline fructose for natural indigo reduction.
• Non-toxic, biodegradable, and food-grade safe.
• Used in 1-2-3 indigo vat formula (1:2:3 ratio with lime and indigo).
• Compatible with indigofera, woad, or natural indigo extracts.
• Maintains steady vat reduction without strong odours or fumes.
• Ideal vat temperature: 40–50°C for optimal reduction.