Viscous food is aspirated into a glass capillary tube with the inner diameter of approximately 0.5 mm if the food is to be examined by transmission electron microscopy. If the sample is destined for examination by scanning electron microscopy, it is aspirated into a Pasteur pipette having the diameter of 1.0 mm. In each case, the lower end of the glass tube is sealed with a droplet of 40°C warm 3% agar sol. After the sol solidifies, the pipette is dipped in the same agar sol and a coating, 0.2 to 0.5 mm thick, is formed around the glass tube by manipulating it while the sol is still liquid. Dipping may be repeated in order to form a uniform coating of desired thickness. The agar gel sleeve is then trimmed, and the pipette is withdrawn, whereby the sample slides into the agar gel sleeve. The free upper end of the agar gel tube is then sealed with a drop of the agar sol. The subsequent preparation of the encapsulated sample for electron microscopy is the same as that of a solid sample.
"Encapsulation of Viscous Foods in Agar Gel Tubes for Electron Microscopy,"
Food Structure: Vol. 7
, Article 12.
Available at: http://digitalcommons.usu.edu/foodmicrostructure/vol7/iss2/12