Enzymes as stabilizers of bread structure

The aim of this project was to study the effects of enzymes (a-amylase, two laccases, lipase and xylanase) on the structure of mixed wheat bread (85 wheat /15 graham flour), especially when baked from prefermented frozen dough. Preparations containing bacterial a-amylase, two laccases, lipase, xylanase, a mixture of xylanase and laccase or a mixture of a-amylase, lipase and xylanase were added to the dough. The dough was divided into two parts for different baking methods: 1) immediate baking after final proofing and 2) freezing for 1 week after prefermentation. Specific volume and firmness of the breads were analysed. The mixtures of enzymes were most effective in improving loaf volume and retaining softness of bread with both baking methods. Freezing of dough affected negatively the ability of lipase and laccase 2 to improve the quality of bread.