Agar-agar, sometimes referred to as China grass, kanten, or just agar, is a gelatinous polysaccharide derived from red algae. Agar is used to gel many food products, such as puddings, desserts, jelly candy, soups, sauces, and more. Agar is a popular vegetarian alternative to gelatin, which is made from animal bones, skin, and connective tissue.

Agar is also a much more powerful gelling agent than gelatin. One teaspoon of agar will give as much thickening power as eight teaspoons of gelatin.

The use of agar-agar in foods is based on its inherent properties:
• High gelling capacity
• Wide pH working range
• Resistance to heat treatment
• Large hysteresis (difference between melting and gelling points)
• No effect on flavours
• Reversible gels
• Gel stability

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