Effect of cold storage and shelf life on physiological and quality traits of early ripening pear cultivars

Abstract

Similar to other species, pear storage is cultivar-specific such that many early ripening cultivars often have limited storability. The effect of cold storage (2°C) on the qualitative traits of six summer pears (Pyrus communis L., namely cvs. “Carmen”, “Coscia”, “Etrusca”, “Precoce di Fiorano”, “Tosca” and “Turandot”) was investigated. The physical–chemical (weight loss, firmness, soluble solid content and titratable acidity) and sensory (fruit juiciness, sweetness, sourness, aroma, graininess and hardness) evaluations were performed after four, eight, 12 and 16 weeks at 2°C and after a five-day period at 20°C (shelf life). The maximum weight loss was recorded in “Precoce di Fiorano”, ranging from 3.6% to 6.0% after eight and 12 weeks of cold storage, respectively. Additionally, the titratable acidity (TA) was affected by the cold storage, and we observed some cultivar-specific changes. “Carmen” and “Tosca” showed a similar percentage decrease in the TA values compared to all other tested cultivars. A multivariate statistical approach, including a principal component analysis, reduced all datasets into three independent components, which accounted for 78.83% of the total variability and provided a global view of the early ripening pear cultivars in response to cold storage. “Precoce di Fiorano” showed rapid fruit decay as the cold storage period progressed; this cultivar preserved its physical–chemical and sensory traits only for a short cold storage period (i.e., four weeks), whereas “Etrusca”, “Carmen” and “Turandot” can be refrigerated for eight weeks with acceptable changes in their organoleptic characteristics. “Coscia” and “Tosca” showed the longest storability (i.e., 16 weeks).