Antistaling properties of encapsulated maltogenic amylase in gluten-free bread.

Staling of bakery products especially gluten-free products is a challenge on the development of these products. For retarding staling of gluten-free bread, maltogenic amylase (MAase) at concentrations of 8.2, 45, and 82 mg/ml was encapsulated into beeswax (BW) at 1%, 2.5%, and 4% levels. Results showed the treatment with 8.2 mg/ml MAase and 2.5% beeswax had the highest encapsulation efficiency (42.04%) and chosen for subsequent experiments. The size of encapsulated particles was 362.70 nm and had a zeta potential of -15.35 mV. Surface morphology of encapsulated MAase was almost spherical with layered appearance. The free and encapsulated MAase with the activity of 5.2 µmol/min were used in gluten-free batter and breads, respectively. In the rheological tests, batters containing free and encapsulated MAase showed lower cross over point than control batter (without enzyme or wall material) (59 and 53 Hz, respectively). Encapsulated MAase contained bread had darker crust, whiter and softer crumb, and more aerated structure in comparison with free MAase loaded one. Both breads containing MAase as free or encapsulated had higher moisture content and water activity in crust and crumb than control bread. However, bread with free MAase had softer crumb after four days of storage, and bread with encapsulated MAase had higher sensorial acceptability than other breads after 2 and 4 days of storage.