Figure 6.

SHG imaging of potato starch granule. Different polarizations of the fundamental laser radiation were used as indicated in the bottom left corner of the panels, including linearly polarized light oriented horizontally (a) and vertically (b), as well as circularly polarized light (d) and (e). The polarization anisotropy image shown in (c) was calculated from images (a) and (b). Image (e) presents a pre-treated starch granule in 68 °C water for 20 s and shows a reduction in SHG intensity due to the heat treatment. The scale bar in (a) is 3 μm and 20 μm for (e). A schematic model of a starch granule is shown in (f).