Encapsulation of ginger oleoresin with a combination of maltodextrin and skim milk powder as wall material

Abstract Ginger oleoresin has active ingredients that are very sensitive to temperature, light, process and storage conditions. Its thick and sticky physical properties also make it difficult in application and handling. Encapsulation is the solution to overcome this problem. The purpose of this study is to select the concentration of maltodextrin and skim milk powder as wall material, the ratio of emulsifier to oleoresin, and to determine the best formulation affected by the ratio of wall material to oleoresin on the characteristics of encapsulated ginger oleoresin. The best formula for encapsulation is from the ratio of maltodextrin and skim milk powder 0.5 : 1.0 as wall material and oleoresin concentration is 15% of the wall material. This treatment resulted in 92.31% encapsulation efficiency. Increase of maltodextrin concentration leads to increase emulsion viscosity, decrease emulsion stability and increase solubility in water, meanwhile increase of skim milk powder and oleoresin concentration leads to increase the encapsulation efficiency. GC-MS analysis of essential oils in oleoresin and in microcapsules show that there is no different composition of active compounds. The application of ginger oleoresin microcapsules on instant ginger tested by hedonic test found that the highest score consisted of 0.3 g of microcapsules in formula.