Annona Species Monograph.pdf - Crops for the Future

Chapter 11. Harvest & Processing
independent and probably started at fruit detachment (Bruinsma and Paull,
1984; Paull, 1990). After the climacteric peak, volatile compounds are
released, sugar and organic acid concentrations decrease, and there is a loss
of fruit quality. The degree of skin darkening is a useful marker for these
stages (Paull et al., 1983). The best time for soursop consumption is 6 to 7
days after harvesting (Paull, 1982).
Sugar apple fruits soften during their second ethylene peak. The physicalchemical
properties of sugar apple change very quickly after this peak, and
abscissic acid increases dramatically and may have a role in fruit ripening
(Tsay and Wu, 1990). Sugar apple fruits reach physiological maturity 15 to
17 weeks after pollination, when soluble solids and titratable acids increase
(Pal and Kumar, 1995; Mosca et al., 1997 a). Mature sugar apple fruits, at
ambient temperature (28 ± 3°C), ripen 2 to 5 days after the harvest point.
Ripening is completed and fruits should be consumed when softening is
apparent, and also when the soluble solids content reaches 28 o Brix and
titratable acids fall to 0.3% (Pal and Kumar, 1995; Mosca et al., 1997 a).
11.3.2 Handling
Annona fruits usually ripen 3 to 7 days after harvesting, thus becoming soft
and easily injured. Careful, appropriate handling and transportation of fruit is
necessary to avoid skin bruising. The fruits are very delicate, so one layer of
fruits per box is recommended for storage and for shipment. If 2 or 3 fruit
layers are used, fruits must be protected with soft cushioning between them
(Calzavara and Müller, 1987; FDA, undated). A single layer in trays
containing 6 to 8 kg of fruits is best (George et al., 1987; Accorsi and
Manica, 1994). As long as the fruits stay firm it is possible to transport them
to distant markets, but they should be wrapped individually with soft
materials, such as paper bags or polystyrene gloves (Salunkhe and Desai,
1984; Coronel, 1994; Lucas, 1994). A pre-cooling treatment prior to
shipment improves the post-harvest life (George, 1984), except for sugar
apple (Singh, 1992).
Aseptic treatment of tools and containers helps to prevent post-harvest
infections from pests and diseases. These routines include the immersion of
pruning scissors in fungicide solution (benomyl 1 g a.i./l) after every fruit
harvested, to avoid transmission of fungal diseases, mainly Lasiodiplodia
theobromae (Alves et al., 1997; Mororó et al., 1997).
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