Quality of pomegranate peel cultivar Valenciana as determined by different drying methods

Abstract

Abstract The pomegranate fruit exhibits medicinal properties due to the nutraceutical characteristics, especially of its peel. The objective of this study was to analyze the influence of different drying methods on the physicochemical and biochemical characteristics of the pomegranate peel. The experiment was conducted in a completely randomized design in subdivided plots: 4 (full sun [SUN], drying chamber [DC] at 60 ± 2 °C, cold chamber at 10 °C and 60% relative humidity (RH) [CC], solar dryer [SD]) × 2 (presence or absence of 1% ascorbic acid [AA]). The analyzed variables were mass loss, index of drying heterogeneity (IHD), Hue internal (LI, CI, HI) and external (LE, CE, HE) angles, as well as Chroma, of the peel, and finally, total phenolic compound (TCFT) and flavonoid (TFLA) content. DC treatment led to the shortest drying time, followed by SUN and SD treatments. A reduction in IHD was observed with respect to time, which was more pronounced in DC treatment. CC treatment produced a more positive response both for LI and LE. TCFT and TFLA content produced from DC treatment presented an interaction effect, which was reduced by the application of AA. On the other hand, dehydration without the application of AA in the drying chamber or in full sun resulted in the best responses in TCFT and TFLA content.