α,α-Trehalases

Enzymes that hydrolyse α,α-trehalose, the non-reducing disaccharide of two glucose units linked α-1,1, into two molecules of glucose. Trehalose is prized in food technology as a protectant: it stabilises proteins, membranes, and flavours during drying and freezing, which is why it is added to frozen foods, dried fruits, and baked goods. Trehalases in yeast and in the human gut determine how this sugar is metabolised; baker’s yeast expresses trehalase to mobilise its trehalose reserves when fermentation starts, affecting dough performance. Measuring trehalase activity helps explain trehalose utilisation in fermentations, and the enzyme is a research tool for carbohydrate biochemistry.