Abstract
Odour is an important quality factor in the selection of the apple. How many chemical constituents are there in apple odour and how to quickly detect them is a subject in food, gardening and computer science. With the development of sensor, network communication and embedded computer technology, the electronic nose research becomes a hot topic. The chemical constituents of odours from different apple cultivars were studied in this paper. It is showed that the smell of fresh, good quality apple, the content of the chemical constituents is balanced. According to the characteristics of apple odours, it carries on exploratory research for the apple odours detection as the apple quality identification basis. It designs a portable apple odour detection system with six SnO2 gas sensors as its odour collector and TMS320VC5402 as its processor. There is other hardware such as high precision A/D converter MAX1403, a 3 * 5 keyboard, and LCD in the system. It introduces interface circuit DSP to A/D converter and keyboard with the characteristics of different varieties of apples odours. A BP neural network is applied in the pattern recognition of apple odours. It studies on the extraction method of characteristic value, the improving for BP algorithm, the BP neural network transplanting to DSP platform. This system can automatically identify apple odour and its application will provide a new method for apple quality identification.
