Equipment: Confocal scanning laser microscopy
Confocal scanning laser microscopy is similar to epi-fluorescence microscopy, where a fluorescent dye is added to label the component of interest. General protein and fat dyes can reveal ingredient distributions in real products (Fig. 4). A key feature of confocal microscopy is three-dimensional imaging of food structures. Additional features have been added to our microscope including a micro-tensile testing stage for solid foods (Fig. 5) and a cryo-optical shearing stage for liquid/semi-solid foods. These attachments will facilitate the real-time study of food structures during shearing and tensile testing.
Figure 4. Confocal scanning laser micrograph of bread showing starch (brown) fat (purple dots)
and gluten network (red). Multiple dyes were used to simultaneously image the different components.
Figure 5: Confocal image set showing fracture path through a fat filled whey protein gel formed at different pH’s.
The microstructure of the gel affects protein fracture properties and fat (yellow) mobility and release.