Fei tecnai 12 biotwin electron microscope

Confocal Scanning Laser Microscopy. Each ice cream mix (2 mL) was dyed with 10 μL of fluorescein isothiocyanate (0.1% wt/vol in acetone) and Nile red (0.01% wt/vol in ethanol). The dyes were added to the mixes 24 h before observation under an Olympus Fluoview 1000 confocal microscope (Olympus Corp.) at excitation wavelengths of 488 and 633 nm for the blue and red fluorescent probes, respectively. The fluorescing images were overlaid, and the location of the fat and protein was determined. This method was modified from He et al. (2019) (link).
Cryogenic Electron Microscopy. Non-HPJ-treated serum and 400 MPa-treated serum were observed under cryogenic electron microscopy following methods described by Hettiarachchi et al. (2018) (link). Briefly, the samples were diluted 30-fold with protein-free serum. Then, 3 mL of each sample was placed onto a glowdischarged perforated carbon film supported on a 200-mesh copper grid (Ted Pella, Redding, CA). The grids were vitrified by submersion in liquid ethane and transferred into a single-tilt cryoholder under liquid nitrogen. The samples were then observed using an FEI Tecnai 12 BioTwin electron microscope (120 kV; FEI Company, Hillsboro, OR), and images were selected from approximately 20 images taken with a Gatan Orius SC 1000 CCD camera (Gatan Inc., Pleasanton, CA).

Non-HPJ-treated model milk, 400 MPa-treated skim milk, and 400 MPa-treated model milk were observed using cryogenic transmission electron microscopy (Cryo-TEM), following the methods described by Hettiarachchi et al. (2018) (link) with slight modifications. Samples were diluted 10-fold with distilled water before being added onto a glow-discharged perforated carbon film supported on a 200-mesh copper grid (Ted Pella). The grids were then vitrified in liquid ethane and transferred into a single-tilt cryoholder under liquid nitrogen. The samples were observed with an FEI Tecnai 12 BioTwin electron microscope (120 kV; FEI Company), and ~20 representative images were taken with a Gatan Orius SC 1000 CCD camera (Gatan Inc.).