Thin layer air drying of French fried potatoes

Abstract

Summary A drying system was designed and constructed to investigate the thin layer air drying of French fried Russet Burbank potatoes. This system permitted the weight loss of the sample to be monitored accurately and continuously without removal of the sample from the drying chamber. Constant drying conditions over a practical range were maintained by continuous control using an on-line computer. The drying conditions investigated in this study included dry bulb temperature ranging from 43 to 93C, relative humidity ranging from 10 to 60%, and air velocity ranging from 0.79 to 1.77 m/sec. A logarithmic model was used to describe the drying curve. The factors affecting drying rate are discussed. The dry bulb temperature had a dominant effect at low relative humidity, whereas at high relative humidity other factors also affected the drying rate. Relative humidity affected the drying rate significantly, while air velocity had the least effect on the drying rate. The drying rate constant in the logarithmic model was correlated with relative humidity, dry bulb temperature and airflow rate and a good fit was obtained.