Using a “home-made” cryo-preparation chamber for SEM imaging of milk gel microstructure

A short article for the New Zealand Microscopy In Focus newsletter. Cryo-scanning electron microscopy (Cryo-SEM) is an advanced microscopy technique that allows observations of samples at high resolutions, often with better preservation to the inherent structure of samples compared to the conventional SEM methods. Cryo-SEM is particularly useful for soft matter samples (those with sensitive/delicate structure) such as milk gels. The investment of a complete advanced cryo-SEM system, however, is costly and not always affordable. In this article, we describe the development of a “home-designed” cryo-preparation process, which was used successfully for the microstructure characterisationof yoghurt gels. This unique cryo-preparation device could provide an alternative cost-effective solution for cryo-SEM visualisationof other similar types of highly-hydrated soft matter materials, such as food and hydrogels.