The scavenging activity of encapsulated EBN hydrolysates using different combinations of polysaccharides as wall material by spray drying

Abstract

Encapsulation process has been widely applied in food industry to improve the properties and stability of bioactive ingredients. However, a suitable type of wall material needs to be studied as different wall formulation will produce powders with different characteristics. This research aims to evaluate the influences using different combination of polysaccharides as the wall material on the encapsulation process of edible bird's nest (EBN) hydrolysates. 3% w/v of EBN hydrolysate was encapsulated with 10% w/v maltodextrin (MD), a combination of 9% MD and 1% carboxymethyl cellulose (MD-CMC) and a combination of 9.95% MD and 0.05% xanthan gum (MD-XG). The recovery yield, encapsulation efficiency, moisture content, water activity, solubility, hygroscopicity, morphology, structure and scavenging activity of the spray dried powders were evaluated. Although the recovery yield of MD (24.86 ± 0.13%), MD-CMC (8.57 ± 0.23%) and MD-XG (16.02 ± 0.18%) were significantly different, the encapsulation efficiency of MD (85.97 ± 0.01%), MD-CMC (81.15 ± 0.01%) and MD-XG (86.58 ± 0.01%) were not, proving all the formulations possess high efficiency to encapsulate EBN hydrolysates. MD-XG also showed the lowest moisture content (6.18 ± 1.01%), lowest water activity (0.25 ± 0.01), highest solubility (90.48 ± 0.23%) and lowest hygroscopicity (7.20 ± 0.01%). The highest scavenging activity was observed when EBN was encapsulated with MD-XG (55.89 ± 0.01%), followed by MD-CMC (50.88 ± 0.01%) and the lowest when encapsulated with MD (27.77 ± 0.01%). The morphology of encapsulated EBN hydrolysates depended on the type of wall material and all of them showed an amorphous structure. Thus, different concentration of MD and combination with other polysaccharides can affect the physicochemical properties and scavenging activity of encapsulated EBN hydrolysates.