Real-time monitoring of color variations of apple slices and effects of pre-treatment and drying air temperature


An attempt was made to quantify the contribution of chemical pre-treatment on the color changes of apple slices during hot air drying. The monitored color attributes of apple slices were computed real time at drying air temperatures of 50, 60, and 70 °C. The apple slices dried in a computer vision system (CVS) assisted-hot air dryer both with and without pre-treatment. The quantities of measured color parameters for pre-treated (P.T.) samples were subtracted from the values obtained for untreated (U.T.) samples at the same water content. For this purpose, an artificial neural network was developed and used satisfactorily for mapping out the color parameters of P.T. samples at calculated moisture ratio for U.T. sample to compute the physio-chemically significant difference. From the results, it can be derived that a CVS seems to be a promising tool when it comes to detecting and monitoring the effects of various pre-treatments on being-processed foodstuffs .

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We would like to appreciate the financial fund provided by the University of Tehran for supporting this project.

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Correspondence to Mohammad Hossein Nadian.

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Nadian, M.H., Rafiee, S. & Golzarian, M.R. Real-time monitoring of color variations of apple slices and effects of pre-treatment and drying air temperature. Food Measure 10, 493–506 (2016).

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  • Apple slices
  • Chemical pre-treatment
  • Computer vision system (CVS)
  • Color parameters
  • Artificial neural network