SOLAR OSMOVAC‐DEHYDRATION of PAPAYA

A solar osmotic dryer was designed and constructed to test the utilization of solar energy in the two-step osmovac-dehydration of papaya. Drying rates measured in solar versus nonsolar osmotic dehydration experiments showed that solar osmotic drying had higher drying rates and sucrose uptake in the papaya samples (0.6 cm thick × 4 cm long × 2 cm wide) than in the nonsolar runs. In separate experiments, drying rates from solar vacuumdrying (as a second step of the osmovac-drying process) were about twice those of nonsolar vacuum-drying. Drying rates of both solar and nonsolar vacuum-drying reached the end of the constant-rate period in about 3 h. Sensory qualities of solar osmovac-dried papaya were comparable to those of vacuum-dried or solar osmotic-nonsolar vacuum-dried. These results suggest the possibility of drying rate increase and quality retention in utilizing solar energy in the osmovac-dehydration process.