Influence of intermittent ratio and fruit thickness on Guava fruit drying: An experimental analysis

The intermittent drying behavior of guava (Sodium guajava L) fruit grown in the Ballari (15.1394 0N, 76.92140E) area of Karnataka state, India, were experimentally studied on ATMEGA328 Microcontroller-based dryer. This research aimed to explore the effects of intermittent-ratio, and thickness for guava fruit on the drying curves utilizing a Taguchi design of experiment (DoE) & ANOVA. The drying operation was carried out for 2,3,5 and 7mm thick guava at 1.5 m/sec velocities with different intermittent ratios (α =Toff/ (Ton+Toff), where Ton and Toff are the on and off time of each 1-hour heating cycle) =1,0.25,0 and 0.75, respectively. The drying regime was observed all through a major falling rate. The study articulates that intermittent ratio and fruit thickness of fruit have an important effect on dehydration. The drying rate is found to be optimum for the intermittency ratio α=0.25 thereby reducing the effective drying time. Drying time increased with increased thickness of fruit. The statistical analysis shows, that the Henderson & Pabis and logarithmic model is a superior model to explain the intermittent drying nature of Guava fruit.