European production of peaches and nectarines in 2013 was about 3 million tons, 51% of which were nectarines. An important increase in the proportion of nectarine production has been observed in the last years at most peach production areas.
BigTop® is nowadays considered the reference nectarine cultivar in Europe for fresh consumption, known as a slow-softening rate cultivar and appreciated for its early coloration resulting in greatly colored fruit, optimum fruit size, high sweetness, juiciness and flavor. Recent studies have also shown that it is a particularly suitable cultivar for fresh-cut production.
Spanish scientists have studied the relationships between storage duration and temperature of nectarines harvested at different ripening stages and consumer perception. In the work, Big Top® nectarines from different maturity stages were exposed to different temperatures and periods of storage with the objective of characterizing their effect on standard quality parameters, sensory attributes and consumer satisfaction.
At harvesting, fruit were divided into three categories according to the IAD index (index of absorbance difference) based on Vis spectroscopy. Fruit were classified into three different categories by decreasing values of the IAD (M1: IAD 0.17–0.15; M2: IAD 0.14–0.12; M3: IAD 0.11–0.09) and stored at 20, 10, 4 or −1°C for up to 49 days depending on storage temperature.
Physico-chemical parameters (soluble solids concentration, titratable acidity, flesh firmness) were measured for the three maturity categories at harvest and after up to 49 days of storage.
Consumer satisfaction and sensory attributes were also measured on fruit from all three categories at harvest, as well as on fruit from the intermediate maturity class after storage at the different tested temperatures for up to 49 days. Each consumer, from a panel of 81 consumers, was asked to indicate his/her degree of liking/disliking using a nine-point hedonic scale (1, dislike extremely; 9, like extremely).
At harvest time, consumer's satisfaction increased significantly with maturity stage at harvest, mainly due to an upper sweetness and flavor perception and higher SSC value detected in the most mature class.
For short storage periods, Big Top® nectarines kept at 20°C received the highest scores for peach flavor intensity and overall acceptance. For longer storage periods, no significant differences among temperatures were observed on sensory quality or consumer satisfaction, except for fruit stored for the longest period (7 weeks), for which higher consumer acceptance was found for fruit stored at −1°C than at 4°C. Results suggested that higher acceptance scores were associated mainly to more intense perception of flavor.
Scientists conclude that it is important to differentiate the fruit for direct consumption from that of which will be consumed after a storage period. The results demonstrated the importance of the ripening stage at harvest and postharvest storage temperature and duration in the perception of organoleptic attributes and overall satisfaction of the final consumer. Sweetness and flavor perception should be incorporated in peaches/nectarines postharvest studies in order to predict their effects in consumer acceptance. On the other hand, this work also outlines the importance of considering physicochemical parameters not as goals, but as tools to monitor the optimum quality demanded by the consumers.
