Evaluation of a Machine Olfaction to Classify the Quality of Dried Date Fruit by Electrohydrodynamic, Hot Air, and the Hybrid Drying Techniques

The dried products quality is influenced by the drying methods and different temperatures, especially on their smell and aroma. The electrohydrodynamic (EHD) method as a non-thermal drying method has an increasing effect on the rate of evaporation of product moisture content in ambient temperature and pressure, and preserve quality in dried food products. The objective of this study was to classify the quality of dried dates at three different air velocity by different drying conditions of electrohydrodynamic (EHD in 25 and 35 °C), hot air (HA at 60 °C) and hybrid drying (EHD-HA at 60 °C) techniques based on odor using a multi-sensory olfactory machine. The results showed that dried date fruit quality base on its odor was classified to three classes (1: EHD at 25°C, 2: EHD at 35°C and 3: HA and EHD-HA at 60 °C). The response of metal oxide semiconductor sensors in EHD method at 25 °C was higher than the others which show the aroma of dried date fruit in class 1 is conserved more better than the other classes. Finally, the effective sensors were determined to recognize the odor of date fruit.