Effects of drying methods on nutrients and organoleptic properties of dried pawpaw chips

Abstract

Fruit dehydration is one of the ways of preserving fruits and supplying consumers with healthy and nutritious fruits, particularly when these fruits are in their off-seasons. Pawpaw (Carica papaya L.) is a tropical plant grown for its edible fruit, having commercial importance because of its high nutritive and medicinal value. However, it is highly perishable. Hence, its processing and preservation are important to retain the product quality and nutritional value. This study investigated the effect of drying methods on the nutrient and organoleptic qualities of pawpaw. Fresh pawpaw fruits were purchased at Oje market in Ibadan, Nigeria. The pawpaw samples were sorted, washed with clean water, peeled and sliced into chips, then the chips were dried using five techniques - solar, open sun, oven, cabinet and dehydrator. Fresh and dried samples were evaluated for physico-chemical properties, selected bioactive compounds, colour, fibre, microbial quality and organoleptic properties. Significant (p≤0.05) differences were observed in the effects of the drying techniques employed. The pawpaw samples that were dried in the dehydrator had significantly (p≤0.05) higher amounts of bioactive compounds and TSS (8.10 ± 0.00°Bx). They also had the most appealing organoleptic properties and showed the least bacterial growth (0.14 ± 0.21 x 104cfu/g) in comparison to the samples dried using other techniques and the fresh sample (91.5 ± 13.44 x 104). While the sun-dried samples had the least fungal load (0.05 ± 0.07 x 103) in comparison to the samples dried using other techniques and the fresh sample (315 ± 7.07 x 103). Results also showed that the samples dried in the dehydrator were the lightest (26.81 ± 0.01) and yellowest (11.42 ± 0.00) of all dried samples. Generally, findings from the study showed that dried fruits portray a greater nutrient density and increased shelf life compared to fresh fruits.