Mathematical modelling of thin layer dried potato and effects of different variables on drying behaviour and quality characteristics

Abstract

The drying kinetics and quality characteristics of three potato (Solanum tuberosum) cultivars (Agria, Granola and Marabel) cut into circles and squares were studied at 60 degrees C and 70 degrees C using a convective drier. Drying times were varied between 105 and 220 min depending on variety, shape and temperature and falling rate period was observed during hot air drying. Four mathematical models were fitted to the experimental data. A logarithmic model was found to be the best for all the samples. The results showed that the drying kinetics of potato were significantly affected by variety, shape and temperature. Drying rate was found to be the highest in variety Marabel and it increased with the increase in temperature and was also higher in square-shaped potatoes than circle-shaped ones. Variety significantly affected the total polyphenol content (TPC) of dried potatoes, whereas variety, shape and their interactions had significant effects on their antioxidant capacities (AC). After drying, the highest TPC and AC were recorded for variety Agria. Concerning colour properties, while the drying temperature and shape had a significant effect on L value, variety and shape significantly affected other colour values of potato samples. These results demonstrated that when choosing the most suitable variety for convective drying of potato, it is necessary to consider the quality characteristics as well as the drying kinetics.