Testing of microencapsulated flavours by electronic nose and SPME–GC

The present study deals with the use of metal oxide gas sensors and the headspace techniques for microencapsulated essential oils of thyme, oregano and cassia. The volatile compounds released from the microencapsulated flavours were tested by an array of the gas sensors. The features of individual odours were described using an analysis of the transient responses of the sensors to the aroma. The coating materials were graded with respect to the leakage of volatile components. The volatile compounds leaking from the microencapsulated flavours were collected by the headspace SPME technique and analysed by GC–MS. Based on the results, the Hi Cap 100 was considered to be the least emitting coating material while the Encapsul 855 was the most leaking matrix in our study.