A new method for the determination of saccharin based on thin-layer chromatography and spectrophotometry.

Saccharin is extracted from the acidified liquid food with chloroform. This solvent is evaporated; the residue is dissolved in ethyl acetate and applied on a silica gel GF254 plate. After chromatographic separation, the saccharin band is scraped off and extracted with 1% sodium carbonate solution. After centrifugation, absorbances at 235 and 244 nm are measured, and the difference A235-A244 is obtained. Standards similarly treated permit to get a calibrating plot and calculate the amount of saccharin in the sample. The method has good precision (C.V. 6%) and accuracy (91.2% recovery).

Tyramine content of some Cuban cheeses.

The tyramine content of 8 types of cheeses made in Cuba were determined. Values obtained ranged from 0-425 micrograms/g. Highest results were found in Camembert-type cheese and lowest ones in Salami (processed type) cheese. It may be concluded that patients taking monoamine-oxidase inhibiting drugs should better not eat cheese, except processed or short-maturing types.