EFFECT OF GELATIN ADDITION AND HOT-AIR TEMPERATURE ON THE DRYING BEHAVIOUR AND QUALITY ATTRIBUTES OF SHEA (Vitellaria paradoxa) FRUIT LEATHER

Abstract

Shea (Vitellaria paradoxa) fruit is a widely available wild fruit known for its nutritional and health benefits. However, its seasonal nature and high perishability limit its consumption. This study explored the effects of adding gelatin and using different drying air temperatures (50 °C and 60 °C) on the drying process, energy use, colour, bioactive and sensory properties of shea fruit leather. The findings indicated that gelatin had a positive influence on drying efficiency, while drying air temperature significantly (p<0.05) influenced the drying time. The Midilli et al. model was the best fit in describing the drying process of the shea fruit leather. Moisture diffusivity increased from 3.91 x 10-12 – 2.76 x 10-11 m2/s for both 50 and 60 °C, while activation energy varied between 13.20 and 87.71 kJ/mol. The energy consumption also decreased as the drying air temperature was increased from 50 °C to 60 °C. The different drying air temperatures and gelatin additions significantly (p < 0.05) influenced the colour parameters of the shea fruit leather. The overall colour change (ΔE*) significantly (p < 0.05) increased as drying air temperature increased and decreased as gelatin levels increased. Drying the shea fruit leather at a lower temperature (50 °C) was found to reduce total carotenoid contents, while the highest retention of total flavonoid, total phenolics and total antioxidant contents was observed at 60 °C. Overall liking scores ranged from 5.77 to 6.27 at 50 °C and from 5.80 to 6.27 at 60 °C, with mid-range gelatin levels being generally preferred