Postharvest quality of grapefruit (Citrus paradisi Macf.) produced from initial plantings in Ceará state, Brazil

Abstract

Ceará state, northeast Brazil, is gaining attention as the most significant emerging fruit production region in the country. Citrus, including grapefruit, traditionally cultivated in the south, was recently implanted. However, data on postharvest quality of grapefruit grown under local conditions are nonexistent. A study was designed to examine postharvest quality of locally grown ‘Star Ruby’ and ‘Ruby Red’ grapefruits. Fruits were assessed for size and shape, pulp color, peel thickness, juice content, soluble solids (SS), titratable acidity (TA), pH, SS/TA ratio, and ascorbic acid at harvest and at the fifteenth day of storage. A second set of fruits were accessed for mass loss and peel color. Results suggested that locally grown grapefruits are of good size and shape, presenting orange peel color and reddish pulp color, and appropriate peel thickness. Fruits yielded a high amount of juice, rich in ascorbic acid, and with values of SS, TA, and pH comparable to those found in traditional grapefruit growing areas. SS to TA ratio was above the least recommended for good flavor. Peel color varied from yellow to pinkish. Mass loss increased, while luminosity and hue angle decreased following the same pattern for the two varieties.