Abstract: Garlic powder was prepared by microwave-vacuum and vacuum drying,and then was microencapsulated in order to protect alliinase activity throughout human stomach and improve ratio of alliin transforming into allicin. Studies on the release kinetics of microencapsulated garlic granulates in vitro in simulated intestinal fluid indicated that release of garlic powder can be controlled in intestine by the human stomach condition,which it passes through scanning electron microscope revealed that wall materisals are of good integrity,and core materials are well embedded in the microcapsules. Storage stability of microencapsulated garlic powder was compared with common garlic powder. The glass-transition temperatures of common garlic powder and microencapsulated garlic powder measured by DSC are -2.9 ℃ and 112 ℃ separately. So microencapsulated garlic powder has good storage stability. The thiosulfinates retention of microencapsulated garlic powder remains above 95% after 10 month storage.

Key words: microwave-vacuum drying, garlic powder, microencapsulation, storage stability