FOOD SCIENCE ›› 2011, Vol. 32 ›› Issue (10): 300-303.doi: 10.7506/spkx1002-6630-201110069

• Technology Application • Previous Articles     Next Articles

Optimization of Preparation Process for Vacuum Freeze-drying Highland Barley Green Powder

DUAN Li-hao1,2,CHEN Yuan-tao1,2,*,ZHANG Wei1,WANG Xiao-lan1,2,CAI Lin-sen1,2, FAN Yan-qing2,HA Wen-xiu1   

  1. 1. Department of Chemistry, Qinghai Normal University, Xining 810008, China; 2. Huzhu Highland Barley Research and Development Center, Qinghai Normal University, Xining 810008, China
  • Online:2011-05-25 Published:2011-04-08

Abstract: The effect of vacuum freeze-drying on highland barley green powder was investigated using freeze-drying velocity and retention rate of flavonoids and SOD as the indicators. The optimal process conditions were explored to be pre-freezing temperature of -40 ℃, pre-freezing time of 4 h, loading materiel thickness of 5 mm, working pressure of 60 Pa, sublimation temperature of 40 ℃ and resolution temperature of 50 ℃. Under the optimal conditions, the retention rates of flavonoids and SOD were 69.3% and 20.1%, respectively. The sample revealed bright green color and fresh grass smell. These results indicated that vacuum freeze-drying was a useful method to prepare highland barley green powder.

Key words: highland barley, barley green powder, vacuum freezing, drying

CLC Number: