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.

Optimization of encapsulation of maltogenic amylase into a mixture of maltodextrin and beeswax and its application in gluten-free bread.

In this work maltogenic amylase (MAase) was encapsulated into the mixture of maltodexrin and beeswax (BW) for retarding staling of gluten-free bread. The effects of maltogenic amylase (MAase) concentration (8.2, 45, and 82 mg/ml), maltodextrin with dextrose equivalent (DE) 4-7 (MD) (1, 2.5, and 4%) and, BW (1, 2.5, and 4%) on the encapsulation efficiency (EE) of encapsulated enzyme were optimized using RSM. The optimized formulation was MAase with 8.2 mg/ml, MD 4% and BW 1%, leading to the highest EE (79.35%), thus chosen for subsequent experiments. The prepared particles were 1,190.50 nm with PDI of 0.336 and zeta potential of -8.30 mV. Surface morphologies of produced particles were almost spherical with layered appearance. Batter with this formulation led to higher cross over point in frequency sweep than free enzyme-loaded batter. Lower weight loss, higher volume index, darker crust color, whiter crumb color, more aerated microstructure, less hardness in crumb, and higher sensorial acceptability on the first day and during storage period in the breads containing encapsulated MAase was observed.