Desenvolvimento de um Nariz Eletrônico aplicado à determinação do estágio de maturação em pessegueiros

Abstract

In regions with the predominance of agriculture, inspection of the quality and fruit maturity index in the orchard is usually analyzed by the farmer’s experience, which can be subject to errors and generate a greater cost of time and money. Depending on the fruit harvest period, the fruit may have different qualities at different points in the planting area. Volatile organic compounds (VOCs) vary in quantity and type depending on the different stages of fruit growth. Thus, monitoring equipment that generates a rapid and accurate response to the growth cycle of the peaches in the crop is desirable, together with a low marketing cost. To this end, the electronic noses are an alternative, since it allows online monitoring of the VOCs generated by the crop. In this context, a prototype was developed to identify the maturation of the Eragil peach in the pre-harvest growth cycle, which comprised the period from August to December 2018, in Brazil. Models with the 13 gas sensors made with a metal oxide semiconductor (MOS) and the reduction to 6 sensors were studied with the aid of the Pearson’s Chi-square test, for comparison. Samples with 4 growth stages were used for the training and construction of the model. The 1.92 % error rate in the sample test step using the Random Forest method with linear discriminant analysis for the reduced data set for 6 sensors shows that the device is promising for monitoring of areas with an intense emission of VOCs. The results obtained in this research are satisfactory, in the quantitative (errors) and qualitative comparisons given by the equipment, based on what was found in the bibliographical research, since the applications tend to carry out the measurement of the post-harvest fruit and not the evaluation of the fruit during its growth, in the orcha