A new cryo-STEM method for imaging food colloids in the scanning electron microscope.
A new cryo-scanning transmission electron microscopy (cryo-STEM) technique for imaging casein micelles in a field emission scanning electron microscope is presented. Thin films of micellar casein suspensions on lacey carbon grids were prepared using a modified sample holder developed by Gatan UK. Bright and dark field images were obtained at -135°C showing casein micelles in their frozen hydrated state and in the size range 30-500 nm. Results were compared favorably with published images of casein micelles obtained with conventional cryo-transmission electron microscopy, suggesting that cryo-STEM is a useful alternative technique for visualizing food colloids close to their native state.
Gee
V L
VL
Food Processing & Functionality Department, Moorepark Food Research Centre, Teagasc, Fermoy, Co. Cork, Ireland.
Carey
M A
MA
Auty
M A E
MA
D002364:Caseins / Q000648:ultrastructure; D003102:Colloids; D020285:Cryoelectron Microscopy / Q000379:methods*; D005502:Food; D046911:Macromolecular Substances / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning / Q000379:methods*
D002364:Caseins; D003102:Colloids; D046911:Macromolecular Substances