Horticultural Maturity Indices
At maturity, the fruit naturally falls (abscises) from the
tree at the articulation of the fruit stem with the fruit and
then ripens in 2 to 4 days, with the fruit normally splitting
into segments of irregular width at the stylar end.
Ripening results in an increase in soluble sugars and a
decrease in starch and pulp firmness, all of which occur
before natural fruit splitting (dehiscence) starts.
To prevent natural fruit fall (abscising), fruit may
be tied to the limb or harvested at maturity. Maturity
is judged by appearance (fruit stalk thickness and flexibility,
abscission zone, or carpel sutures), number of
days from flowering, and a hollow sound when tapped
with a wood or rattan stick or knife. Days from flowering
and tapping are the most reliable criteria (Siriphanich
1996). ‘Chanee’ durian takes 2 to 4 days to ripen after
harvest, while ‘Monthong’ durian takes 4 to 6 days,
depending on maturity. Fruit at 85% maturity, based
upon days from anthesis and rind characteristics, ripen to
excellent quality in less than 1 week at 28 to 31°C (82.4
to 87.8°F). Ripening takes longer than 1 week at 22°C
(71.6 °F). Fruit that are 95% mature when harvested have
already commenced ripening, while 75% mature fruit
may ripen with an inferior quality. Fruit collected from
the ground after falling are more subject to disease and
fracture and have a short shelf-life (2 to 3 days), instead
of 7 to 8 days if picked from the tree. In Thailand, the
fruit is harvested with the stem (peduncle) attached and
the fruit stem is wrapped in a leaf or paper by retailers
to reduce wilting and maintain the fresh appearance of