Hydrocolloids absorb water and give consistency to the batter, trapping the gas cells produced by yeast.
Without them, the batter would be so liquid that it would be almost impossible to retain the gas and would result in a dense final product. Hydrocolloids also help to retain moisture and delay staling.
Emulsifiers are stabilising ingredients that reduce the surface tension of emulsions. They locate between two phases (air and dough) allowing one phase to remain suspended in the other one without separating. In gluten-free baking, emulsifiers surround the gas bubbles and prevent coalescing, producing consistent fine bubbles in the crumb instead of big holes. They also produce stronger and more stable doughs with a better crumb structure, loaf volume and longer shelf-life.
Alba Hernandez Beltran, bakery scientist, Campden BRI
Campden BRI provides technical support to the food, drinks and allied industries worldwide. Its activities are built on a programme of industrial relevant research and innovation steered by industry. See campdenbri.co.uk or telephone 01386 842000