2-Alkylcyclobutanones as makers in the detection of irradiated liquid egg -a modified method of processing

Drying for several hours at 100 C may result in a considerable loss of 2-alkylcyclobutanones. It also tends to lead to interfering peaks so that results obtained by mass spectrometry in connection with the SIM technique may wrongly suggest the presence of small amounts of 2-alkylcyclobutanones. An alternative to this procedure is offered by lyophilization. This method also has its limitations in that it is largely dependent upon the available facilities and conditions of lyophilization (duration, vacuum, sample heating). It would therefore appear wise for any laboratory to thoroughly analyze the recovery rate of its lyophilization plant and, if required, to resort to other methods of drying (like short-term drying for 2 h at 100 C). The North Hessian Supervisory Office recommends to avoid drying altogether. Instead, liquid egg should be mixed with large quantities of sodium sulfate and then directly subjected to fat extraction using the Soxhlet apparatus (recovery rate approx. 90%). (orig./vhe)