Establishing a Consumer Quality Index for Fresh Plums (Prunus salicina Lindell)

Plums are primarily marketed for fresh consumption, canning, freezing, jam and jelly. Unfortunately, plum consumption has remained steady or declined. Consumers complain about a lack of flavor quality but are willing to pay for higher quality. Thus, absence of flavor and cold storage disorders are the main barriers to consumption. Plum cultivars are sensitive to gel breakdown, flesh browning and 'off flavors'. Consumer approval and postharvest life are controlled by genotype, quality attributes, harvest date and proper postharvest handling. A consumer quality index (CQI) based on soluble solids concentration (SSC) and minimum firmness is proposed to maximize flavor and postharvest life. In most cases, late harvest increases quality attributes. Our work and industry experience demonstrated that using critical bruising thresholds (CBT) based on minimum firmness measured at harvest acts as a reliable predictor of how late to harvest safely for maximum visual and sensory quality. Plums tolerated late harvest well because of their high tolerance to bruising damage, but suitable postharvest temperature management and selling within the potential postharvest life are required to maintain flavor and avoid the beginning of chilling injury. Thus, to maximize flavor and postharvest life, a CQI based on SSC and minimum firmness measured at consumption is proposed. This article provides guidance on using this CQI, combined with proper postharvest handling techniques, such as correct harvest date determination and temperature management, to maintain quality and increase consumption.