Influence of different combinations of wall materials on encapsulation of Nigella sativa oil by spray dryer

Modulating of microencapsulated virgin coconut oil-based creamer

This work aims to produce a virgin coconut oil (VCO) creamer through two drying stages; spray drying followed by fluidised bed drying, and to examine its antioxidant properties and oxidative stability during different storage conditions. Evaluation of the physicochemical properties of spray dry VCO and oxidative stability of the VCO creamer were performed using peroxide value (PV), antioxidant activity (DPPH), and total phenolic content (TPC) at 25, 4, and 25 °C, respectively, for 8 weeks. Agglomeration process has improved the agglomerated VCO creamer's properties in terms of moisture content (4.34%), solubility (85.2%), water activity (0.32%), and bulk density (0.36 g/cm3). The morphology of agglomerated VCO creamer showed cluster and irregular shapes with enlargement in the particle size, (d32) 395 µm and (d43) 426 µm. The overall oxidative results showed stability for the agglomerated VCO creamer stored at 4 °C in terms of TPC, DPPH and PV over 8 weeks followed by creamer stored at 25 °C which had similar stability with slight differences. The creamer stored at 38 °C showed rapid degradation for all oxidation tests from week 2 onwards. Agglomeration technology has indicated to be effective in the stabilization of virgin coconut oil against lipid oxidation and prolonging its shelf-life.

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Effects of different proteins and maltodextrin combinations as wall material on the characteristics of Cornus officinalis flavonoids microcapsules

The flavonoids in Cornus officinalis (CO) have various pharmacological activities, however, the flavonoid instability limits its application in food and pharmaceutical industries. In this study, Cornus officinalis flavonoid (COF) microcapsules were prepared by using a combination of whey isolate protein (WPI), soy isolate protein (SPI), gelatin (GE), and maltodextrin (MD) as wall materials, respectively. Meanwhile, the encapsulation efficiency, solubility, color, particle size, thermal stability and microstructure as well as the antioxidant capacity of microcapsules were assessed. When the protein/MD ratio was 3:7, three kinds of combined wall materials realized high encapsulation efficiency (96.32–98.24%) and water solubility index (89.20–90.10%). Compared with other wall material combinations, the microcapsules with WPI-MD wall ratio at 3:7 had lower particle size (7.17 μm), lower moisture content (6.13%), higher encapsulation efficiency (98.24%), better water solubility index (90.1%), higher thermal stability (86.00°C), brightness L* (67.84) and higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging capacity (6.98 mgVc/g), and better flowability. Results suggested that WPI and MD could be better wall materials applied in encapsulating COF.