Determination of seasonal influences on sensory attributes of South African cactus pear cultivars

Abstract

This paper reports on the effect of cultivar and season on sensory quality of cactus pear fruit. The sensory quality was evaluated by the Free Choice Profiling (FCP) method over the two agricultural seasons of 2007 and 2008. The five most frequently-used attributes used by the panel were sweet, sour, bitter, fruity and prickly pear, with the corresponding cultivars for season 2007 being Fresno, Robusta, Sharsheret, Malta and Amersfoort. For season 2008, the corresponding cultivars for the same attributes changed to Nudosa, Sharsheret, Robusta, Roly Poly and Ficus Indice, respectively. The FCP technique could successfully distinguish between the two seasons, but not between the majority of the cactus pear cultivars. The exception was Monterey and Robusta where FCP was able to differentiate them clearly from the rest of the cultivars. In an attempt to determine whether sensory quality of cactus pear fruit was influenced by the physico-chemical parameters, Pearson correlation analysis was performed between the physico-chemical and sensory data. Physico-chemical parameters like pulp glucose, pulp fructose and percentage pulp were correlated with sensory attributes like sweet, fruity and prickly pear. The descriptor “sweet” had a positive correlation (r = 0.2477) with pulp glucose and pulp fructose content (r = 0.2636) at a significance level of p < 0.05. A negative correlation at a significance level of p < 0.01 between the taste attributes “prickly pear” (r = 0.4259) and “sweet” (r = 0.3561) and % pulp was observed. “Prickly pear” had a positive correlation (r = 0.3547) with pulp pH at a significance level of p < 0.01.