Abstract: A bread quality-improving composition and a process for the production of bread using the composition. More particularly, a bread quality-improving composition which contains a maltotriose-forming enzyme or a maltotriose-forming enzyme, glucose oxidase and/or hemicellulase and a process for the production of dough and bread using the composition. The bread quality-improving composition renders possible the easy handling of dough without covering it with wheat flour and the like, the exclusion of additives for use in the control of water content, an improvement in elasticity and ductility of bread when baked, the prevention of bread solidification and other problems such as a reduction in bread volume when frozen dough is used and the elimination or reduction of emulsifying agents.

Abstract: A novel .alpha.-1,6-glucosidase having the following properties:(1) Action: The enzyme acts on an .alpha.-1,6-glucoside bond to produce linear amylose;(2) Substrate specificity: The enzyme has the following relative activity to polysaccharides:______________________________________ Polysaccharide Relative activity (%) ______________________________________ Pullulan 100 Maize soluble amylopectin 13.5 Soluble starch 6.7 Oyster glycogen 1.7 Hare glycogen 2.6 Maize amylopectin 3.8 Potato amylopectin 4.0 ______________________________________(3) Km value and Vmax to pullulan: the enzyme has Km value of 0.14 mg/ml and Vmax of 70.0 .mu.mol/min/mg protein;(4) Optimum pH: 5.0 to 5.5;(5) pH stability: The enzyme is stable in the pH range of 4.5 to 6.5 for 30 minutes at 40.degree. C. and in the pH range of 5.0 to 6.0 for 30 minutes at 50.degree. C.;(6) Optimum temperature: Approximately 55.degree. C.;(7) Thermal stability: Treatment at pH 4.