SUMMARY Low‐temperature electron microscopy combined with electron diffraction allows determination of the state of structural preservation as well as that of the solidified cellular water in frozen‐hydrated sections. Apple leaves frozen at high pressure and cryosectioned with glass knives covered with a very thin layer of frozen water exhibit a minimum of artefacts and are thin enough for structural analysis. The Zeiss 902 EM energy‐filtering microscope helps to improve the poor contrast of frozen‐hydrated sections by imaging in the zero‐loss mode. All sections analysed showed the electron diffraction pattern of vitreous water. This is ideal: the character of the liquid phase is preserved. A very high yield of good cryosections is achieved because the samples are vitrified and the friction on the glass knife surface is reduced by a thin ice layer.

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