Experimental design with pellet heating time of 1.00, 1.33, 1.67, 2.00, 2.33, 2.67, 3.00, 3.33, 3.67, and 4.00 min was studied to investigate the effects of pellet heating time on the physical properties (expansion ratio, density and breaking strength) of vacuum-puffed Yukwa. The size and shape of vacuum-puffed Yukwa varied with respect to the pellet heating time.As pellet heating time increased, a values and b values tended to increase. The maximum expansion (4.626) with the lowest bulk density (0.112) was obtained at 3.33 min heating time, whereas the minimum expansion (2.954) with the highest bulk density (0.208) was found at 1 min. The breaking strength of vacuumpuffed Yukwa decreased significantly as the pellet heating time increased. Overall, the heating time had significant impacts on the physical properties of vacuum-puffed Yukwa.

• Xiao-jun Shen(Coconut Research Institute, Chinese Academy of Tropical Agriculture Sciences, China)
• Xiao-yu Li(Coconut Research Institute, Chinese Academy of Tropical Agriculture Sciences, China)
• Gi-Hyung Ryu(Department of Food Science and Technology, Kongju National University) Corresponding author