A new maltogenic amylase from Bacillus licheniformis R-53 significantly improves bread quality and extends shelf life

Maltogenic amylase suppressed starch retrogradation in baked products. Here, a maltogenic amylase-producing strain of bacteria was screened and identified as Bacillus licheniformis R-53. Its coding gene was cloned and over-expressed in Bacillus subtilis WB600. Recombinant maltogenic amylase BLMA exhibited activity of 3235 U/mg under optimal conditions (60 °C and pH 6.5), with a good thermostability and pH stability. Mixolab experiment showed that a concentration of 60 ppm BLMA significantly improved the operating characteristics of dough. Baking test indicated the recombinant BLMA reduced bread hardness by 2.12 times compared with the control. Compared with maltogenic amylase from Novozymes (Novamyl 3D BG) and Angel Yeast Co. Ltd. (MAM100), BLMA has better effect on improving the bread volume, and almost the same effect on reducing hardness, improving elasticity and maintaining sensory as Novamyl 3D BG. Adding BLMA improved bread quality, increased bread volume and decreased hardness during storage, thus extending its shelf life.