Acoustic probing to estimate freshness of tomato

The freshness of vegetables attracts significant interest, because consumers will determine the way of cooking based on the maturity of the vegetable or select better vegetables in supermarkets based on the freshness information. This paper focuses on tomatoes, and reports our preliminary studies on acoustic probing techniques to estimate their storage term. We hit an acoustic probe that sweeps audible band to a sample and capture an transmitted acoustic signal by using a microphone. We collect transmitted signals for samples with various storage terms and the obtained signals are used to train a classifier. In our study, twelve sample tomatoes were measured during fourteen days. We found the amplitude of the transmitted signal obviously decreases as the tomato matures.