Influence of maturity stages on postharvest physico-chemical properties of grapefruit (Citrus paradisi var. ‘Shamber Tarnab’) under different storage durations

The present study was conducted to evaluate the effect of maturity stages on the physicochemical characteristics of grapefruit (Citrus paradisi cv. ‘Shamber Tarnab’) under storage conditions for 60 days at ambient temperature (16±1 °C with 55-60% relative humidity). Grapefruits were harvested at different maturity stages, namely mature green (MG) and full ripe (FR). The fruits of both stages were assessed for different physical quality parameters at 15 days interval. The experimental results showed that ascorbic acid content, titratable acidity, fruit firmness, percent disease incidence was higher at FR stage. In contrast, weight loss, percent juice content, total soluble solid (TSS), and TSS/acid ratio at MG (mature green) were lower than that of FR fruits. Regarding storage durations, the fruit firmness, titratable acidity, percent juice content, ascorbic acid content decreased significantly, whilst total soluble solid, TSS/Acid ratio, weight loss, and percent disease incidence increased significantly with the extension of storage duration from 0 to 60 days. As concerned to its interactive effects, the highest ascorbic acid content, titratable acidity, percent juice content, and maximum fruit firmness were observed in fresh grapefruit, harvested at (MG) mature green stages, whereas the maximum total soluble solid, percent disease incidence, and TSS/Acid ratio were recorded in fruit harvested at (FR) full ripe stage, stored for 60 days at room temperature. Similarly, the Pearson’s Correlation Analysis (p> 0.05) of grapefruit was positive effect for most of the quality traits of grapefruit at different storage durations and maturity stages. It was concluded that grapefruit could be harvested at the mature green stage (MG) for sustaining quality attributes up to 60 days of storage at room temperature.