Potential of microencapsulation to protect ascorbic acid under different temperature and pH during heating process

Potential of microencapsulation to protect ascorbic acid under different temperature and pH during heating processAbstractAscorbic acid (Vitamin C) is an important nutritional component which increases quality and technological properties of food but is naturally unstable. In order to increase the stability of ascorbic acid under a variety of processing conditions, the potential of microencapsulation has been investigated in this work. Six microcapsule formulations were prepared containing gum Arabic (GA), maltodextrin (MD) and chitosan at ratios of 4:1:1, 1:4:1, 1:1:4, 2:2:2, 3:2:1, 3:1:2, respectively. Encapsulation efficiency was varied depending on microcapsules composition and ranged from 40.5% to 80.4%. Microcapsules with higher efficiency were then further characterized by SEM and DSC. Finally, the retention of encapsulated ascorbic acid was evaluated under different simulated process conditions in term of temperature (50, 70, 90 ºC) and pH (3, 4, 5) over time (0 to 200 min). The rate of loss for ascorbic acid varied widely between samples and those encapsulated were more stable at different temperature and pH especially at 50 ºC and pH 5