Effect of ethylene and temperature conditioning on sensory attributes and chemical composition of 'Bartlett' pears.

'Bartlett' pears are resistant to ripening after harvest. Ethylene and temperature conditioning have been successfully used to stimulate fruit ripening with improved eating quality over non-conditioned fruit. However, few studies have evaluated the effect of different conditioning treatments on the sensory attributes of the fruit. In this study, we compared a descriptive sensory evaluation with the chemical composition of 'Bartlett' pears after the fruit were exposed to the following conditioning treatments: 2 d 100 μl L-1 ethylene, 14 or 7 d at 0 °C, 7 or 3 d at 10 °C, or untreated control at 20 °C. Fruit were softened to 27, 18 and 9 N firmness before evaluation. At 9 N, fruit conditioned at 0 °C produced high levels of esters, and fruit conditioned at 0 °C for 14 d also were high in sweet taste and fruity flavor attributes. Fruit treated at 10 °C had lower concentrations of esters, but fruit treated at 10 °C for 3 d was high in sweet taste perception. Ethylene treated fruit produced low levels of esters and high levels of aldehydes and were associated with apple aroma, similar to the untreated control fruit. Water soluble pectin levels were highly and positively correlated with juiciness and sweetness and negatively correlated with firmness, crunchiness, and grittiness. Future studies should determine whether consumer liking of 'Bartlett' pear fruit is also influenced by conditioning treatment. [ABSTRACT FROM AUTHOR]