title: Ultrasound assisted immersion freezing of broccoli (Brassica oleracea L. var. botrytis L.).
abstract: OBJECTIVE
  The aim of this study was to research the ultrasound-assisted freezing (UAF) of broccoli.
  
  
  METHODS
  CaCl2 solution was used as freezing medium. The comparative advantage of using UAF over normal freezing on the freezing time, cell-wall bound calcium to total calcium ratio, textural properties, color, drip loss and L-ascorbic acid contents was evaluated.
  
  
  RESULTS
  The application of UAF at selected acoustic intensity with a range of 0.250-0.412 W/cm(2) decreased the freezing time and the loss of cell-wall bound calcium content. Compared to normal freezing, the values of textural properties, color, L-ascorbic acid content were better preserved and the drip loss was significantly minimized by the application of UAF. However, when outside that range of acoustic intensity, the quality of the ultrasound-assisted frozen broccoli was inferior compared to that of the normally frozen samples.
  
  
  CONCLUSIONS
  Selected the appropriate acoustic intensity was very important for the application of UAF.
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, 214122 Wuxi, Jiangsu, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Xin
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, 214122 Wuxi, Jiangsu, China; School of Food Science and Technology, Jiangnan University, 214122 Wuxi, Jiangsu, China. Electronic address: min@jiangnan.edu.cn.
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.affiliation: School of Health Sciences, University of Ballarat, Mount Helen, Victoria 3353, Australia.
authors.forename: Benu
authors.initials: B
authors.lastname: Adhikari
mesh_terms: D001205:Ascorbic Acid / Q000032:analysis; D001937:Brassica / Q000737:chemistry* / Q000528:radiation effects*; D002118:Calcium / Q000032:analysis; D002122:Calcium Chloride / Q000737:chemistry; D002473:Cell Wall / Q000737:chemistry / Q000528:radiation effects; D003116:Color; D005519:Food Preservation / Q000379:methods*; D005615:Freezing; D012996:Solutions; D014465:Ultrasonics / Q000379:methods*; D014815:Vitamins / Q000032:analysis
chemical_list: D012996:Solutions; D014815:Vitamins; D002122:Calcium Chloride; D001205:Ascorbic Acid; D002118:Calcium
keywords: Broccoli; Freezing; Microstructure; Quality; Ultrasound