Effect of storage temperature and ethylene treatment on guava (Psidium guajava L.) fruit ripening

Abstract

Storage of guava (Psidium guajava L. cv. Beaumont) at 15 °C delayed deterioration of quarter-yellow and half-yellow fruit and allowed gradual ripening of mature-green fruit to full color in 11 days. Ripening was delayed most by the lowest temperature (10 °C) for the mature-green fruit, and decreasingly less for the riper fruit and higher temperatures (20 °C). Treating fruit with 100 μl l−1 ethylene (C2H4) at 20 °C for 24 h resulted in a significant increase in the rate of skin yellowing and softening of immature-green fruit, whereas ethylene-treated mature-green and quarter-yellow fruit did not differ from nontreated control fruit in rate of skin yellowing and softening. Titratable acidity (TA) and total soluble solids (TSS) of fruit at mature-green and later stages were not significantly affected by ethylene treatment. Immature-green fruit, whether or not treated with ethylene, became ‘gummy’ and shrivelled during ripening and had a higher juice viscosity.