Olive (Elaeagnus latifolia) pulp and leather: Characterization after thermal treatment and interrelations among quality attributes

Abstract

The effect of thermal treatment (60 °C for 0–45 min) on the flow behavior of wild olive (Elaeagnus latifolia) pulp, and the sensory and textural properties of the developed fruit leather were investigated. The suitability of Cross, Carreau and Carreau-Yasuda models was examined to explain the flow behavior of olive pulp; Carreau model with high correlation coefficients (r = 0.985–0.998, p ≤ 0.01) was the best. The experimental yield stress and apparent viscosity of thermally treated pulp were higher than that of native pulp. The leather obtained after 15min of heat treatment followed by drying of pulp exhibited high peak force (0.87 N), failure energy (2.35 mJ) and elongation (20.5%). The cluster analysis concerning the attributes of the pulp and leather indicated that the apparent viscosity and elongation possessed a poor inter-relation. The physicochemical properties showed that the prepared leathers contained high amounts of phenolic compounds. Thermal treatment of olive pulp is thus a feasible method to prepare health-benefitting fruit leather.