Microencapsulation of ginger (Zingiber officinale) extract by spray drying technology

• Ginger (Zingiber officinale Roscoe) extract (GE) contains high levels of 6-gingerol.
• Microencapsulation process can reduce the concentration of 6-gingerol in GE.
• Microencapsulation process can influence the antioxidant activity of GE.

The aim of this study was to evaluate the effect of microencapsulation of ginger (Zingiber officinale Roscoe) extract using maltodextrin (MD) and/or gum arabic (GA) as microencapsulation agents on its 6-gingerol content, total phenolic and antioxidant activity. Four slurries containing 95 mL/100 mL of ginger extract (2 g solids/100 mL) and 5 g/100 mL of a blend of maltodextrin:gum arabic of weight ratios (4:1, 1:4, 5:0, and 0:5 g:g) were prepared and they were separately spray dried at 160 °C inlet air temperature to produce ginger extract powders. Ginger extract contained 20.6 ± 0.2 (mg/g solids) 6-gingerol, 7.7 ± 0.6 (mg/g solids) gallic acid equivalents and had an antioxidant activity of 19.9 ± 0.8 (μmol Trolox/g solids). Microencapsulation resulted in a decline in the quantity of 6-gingerol present in ginger extract regardless of the maltodextrin and gum arabic blend. Microencapsulation of ginger extract also reduced gallic acid equivalents and antioxidant activity. Ginger extract dried with maltodextrin:gum arabic (1:4 g:g) and (0:5 g:g) had larger particle size than that dried with maltodextrin:gum arabic (4:1 g:g) and (5:0 g:g). Maltodextrin:gum arabic (4:1 g:g) and (5:0 g:g) had better morphological properties than maltodextrin:gum arabic (4:1 g:g) and (5:0 g:g). Microencapsulated ginger extract powder may be used as a novel food ingredient.