An aroma sensor for assessing peach quality

A gas concentration transducer has been used to build an aroma sensor whose signals are related to concentration levels of delta and gamma decalactones, which are the main volatiles that compose peach aroma. In order to estimate the efficiency of assessing peach quality with the sensor, its readings were compared with peach quality classes determined by experts depending on fruit external appearance (colour, firmness, and estimated maturity). The sensor was able to reproduce this classification with a 75-85% success rate. No clear relationship was found between the signal of the sensor and other quality parameters, such as sugar content or firmness. However, preliminary tests have succesfully demonstrated the possibility of using these transducers to detect rotten fruit in cool chambers. (C) 1999 Silsoe Research Institute.