Postharvest treatments to reduce chilling injury symptoms in stored ...

lychee, and nectarine; it has been approved for grapefruit, papaya, and mango. The
disadvantage of this treatment is fruit weight loss and shrivelling which occurs due to low
air humidity.
2.3.3 Hot water-treatment (HWT)
Hot water (HW) is an effective heat transfer medium and, within a short time a
uniform temperature profile will be maintained (Couey, 1989). The additional benefit of
HWT is that it can control postharvest diseases such as anthracnose and stem end rot
(Couey 1989; McGuire 1991). This treatment is commonly used for disinfestation of
mango from fruit flies (Sharp et al., 1988, 1989; Sharp 1986; Segarra-Carmona et al.,
1990; Nascimento et al., 1992). This treatment is cheaper than any other heat-treatment
and is also effective on commercial scale in the USA. Recommended temperature ranges
are between 43-46 °C; above 46 ºC the fruit experiences excessive damage. Usually a
single dip procedure is used either in batch process or continuously for 65-90 min
depending on fruit size and cultivars.
2.3.4 Physiological responses to heat-treatment
Physiological response to heat treatment in the fruits has been summarized by
Jacobi et al., (2001), according to that:
i) Heat-treatment increases fruit heat tolerance which depends upon a number of
factors including species, stage of fruit maturity, fruit size, exposure to
different environmental factors, time, duration and type of application.
ii) When harvested fruits are transferred from ambient growth temperature to an
elevated temperature, stress is induced and the impact depends upon length of
exposure and temperature difference.
iii) Heat-treatment also develops external or internal heat injuries in many
cultivars.
iv) Heat-treatment can affect fruits ripening either inhibiting, promoting or
disrupting the ripening process.
v) Heat-treatment accelerates the yellowing of the mango fruit skin and
uniformity of skin color is also observed. However, in many cultivars fruit
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