Figs - Tropical and Subtropical Fruits: Postharvest Physiology, Processing and Packaging - page 445

changes. After harvest, figs may continue to soften and
change color, but their sugar level does not increase (Ak-
soy, 1997; Rodov et al., 2002). As a result, the fruit picked
at underripe stage never reaches optimal flavor.

Fungicide treatments can control many postharvest fig
pathogens (Michailides et al., 1996 ; Nitta, 1997), however,
applying fungicides on edible figs is often prohibited (Al-
fieri and El-Gholl, 1993). Bordeaux mix is a wide-spectrum
copper-based fungicide and pesticide applied in orchards
for more than a century. Although copper spray residue on
edible fig fruit was deemed undesirable in the 1970s (Wani
and Thirumalachar, 1973) , the treatment continued to be
used on figs in Brazil (Raga et al., 2003); fruit from that
region usually can be recognized by greenish sediment on
the skin surface.
Other recommendations to reduce postharvest diseases
are controlling orchard insects to reduce fruit damage and
transmission of fungi; using effective control of preharvest
diseases; enforcing strict sanitation of picking and trans-
porting containers; supervising careful handling to mini-
mize abrasions, cracks, and other physical damage; avoid-
ing picking figs for fresh market from the ground; enforcing
prompt cooling to 0 ◦ C(32 ◦ F); and maintaining the cold
chain all the way to the consumer (Crisosto and Kader,
2009).

Physiological disorders
Figs are susceptible to some physiological disorders dur-
ing the fresh fruit storage. The controlled atmosphere (CA)
related disorders are important as extended storage in CA
can result in loss of characteristic flavor. Figs exposed to
less than 2% O 2 and/or more than 25% CO 2 develop off fla-
vors due to fermentative metabolism (Crisosto and Kader,
2009).

Postharvest pathology
Figs are attacked by a range of pathogens. Various fungal
species, such as Botrytis cinerea, Rhizopus nigricans, Al-
ternaria alternata, Aspergillus spp., Penicillium spp., and
Cladosporium herbarum, were registered as causal agents
of postharvest fig rots (Piga et al., 1995; Nascimento et al.,
1999; Montealegre et al., 2000):

Quality characteristics and criteria
Quality descriptors of fresh figs comprise fruit size, firm-
ness, skin color, flesh color, flavor, sugar content, and acid-
ity. Other quality indices include defects (such as bird-peck,
sunburn, scabs, cracks, and shriveling), insect infestation,
and decay (Crisosto and Kader, 2004).
The postharvest behavior of fruit is greatly affected by
cultivar characteristics. Turkish 'Bursa Siyahı' is charac-
terized by large dark-colored firm fruit, high sugar content,
and long postharvest life and is the best fig cultivar for
fresh consumption. 'Bursa Siyahı' belongs to the Smyrna
type and therefore requires Blastophaga pollination for fruit
development. At optimal conditions 'Bursa Siyahı' main-
tains high quality for up to 6 weeks (T urk, 1989) and is
not prone to cracking (Aksoy and Ana¸, 1994b). Aksoy
(1981) studied cultivar effects on fresh fig storage, espe-
cially, weight loss; the fastest desiccation was observed in
'Sarılop' ('Calimyrna') fig, a cultivar primarily selected for
drying, while the cultivar 'Akca,' used for fresh consump-
tion, demonstrated 2.5 times slower weight loss. Comparing
fig cultivars by their response to vibrational stress revealed
'Masui Dauphine' as a sensitive cultivar while 'Celeste'
and 'Brunswick' were relatively tolerant to vibration (Mao
et al., as cited by Flaishman et al., 2008). In a similar study
on 'Sarılop,' 'Bursa Siyahı,' and 'Yediveren' figs, the latter
cultivar was found to be the most resistant to transporta-
tion mechanical stresses whereas 'Sarılop' was the most
susceptible (Aksoy et al., 2003).

Alternaria rot: Caused by Alternaria tenuis, appears as
small, round, brown-to-black spots over the fruit surface.
Any cracks on the skin make the fruit more susceptible
to the rot.
Black mold rot: Caused by Aspergillus niger, appears as
dark or yellowish spots in the flesh with no external
symptoms. At advanced stages, the skin and flesh turn
slightly pink color and white mycelia with black spore
masses follow.
Endosepsis (soft rot): Caused by Fusarium moniliforms,
appears in the cavity of the fig making the pulp soft,
watery and brown with sometimes an offensive odor.
Souring: Caused by various yeasts and bacteria, is a prehar-
vest problem resulting from yeasts and bacteria carried
into the figs by insects, especially vinegar flies, resulting
in odors of alcohol or acetic acid.

Even when not displaying visible fungal decay, over-
ripe figs in storage undergo rapid degradation, expressed
as excessive softening, tissue maceration, and exudation of
syrupy liquid from the ostiole, which eventually may stim-
ulate the growth of epiphytic microorganisms. As a result,
termination of storage life of fig fruit is typically a result of
combined effect of physiological (overripening) and patho-
logical (decay) factors. It may take from 1 to 2 days to 4 to
6 weeks to reach this degradation stage, depending on envi-
ronmental conditions (primarily temperature), initial fruit
ripening stage, and cultivar peculiarities.