Determination of shrinkage characteristics of pumpkin discs during convection, microwave, and combined drying using computer-aided technique: Image processing application

Image processing techniques are used in several fields and gained popularity in food processing. In this study the drying and shrinkage characteristics of pumpkin slices were determined by using thresholding method. A continuous measurement of the weight change and an imaging of the pumpkin slices to measure the area of the sample before and after drying were performed to define the shrinkage characteristics. The drying times of the pumpkin discs were between 8.5-9 and 55-65 minutes for 2 mm thick samples. Drying in the microwave oven resulted in 85% less time and lower values of water activity were obtained. The shrinkage rate of samples dried by microwave drying method (46-60%) was found to be statistically lower than samples prepared by convection drying method (58-73%) (p < 0.05). Non-parametric Spearman correlation coefficient technique was used to evaluate the relationship between the moisture content and shrinkage for drying under different conditions.Practical application With the advancement of image processing technologies, there is significant potential for food safety and preservation. This research will lead to advancements in the fields of food quality and preservation analyses for food manufacturers. Furthermore, this technology can be employed in the food business for quick quality determination for mass production. This research indicates that image processing may be used to evaluate food shrinkage characterization. It is expected that the application of this technology will serve the food sector by optimizing process parameters and energy usage, saving time, and developing sustainable systems, particularly in the large-scale food industry where mass manufacturing is carried out.