Advances in Postharvest Disinfestation of Fruits and Vegetables Using Hot Water Treatment Technology-Updates from Africa

Hot Water Treatment (HWT) provides adequate phytosanitary assurance that treated fruits and vegetables exported abroad are free from devastating quarantine pests. Two systems for HWT are currently available for commercial use namely the batch/jacuzzi and the continuous flow system depending on user requirements. Several protocols have been developed the world over and a few in Africa, but adoption has been lagging because of various factors chief among them lack of large scale validations of experiments to guide application at the commercial level. Mango, Bell pepper, avocado, and French beans play an important role in the livelihoods of people in Africa. However, their export is constrained by pests such as the invasive Oriental fruit fly, the false codling moth, and thrips. To circumvent this issue, disinfestation HWT protocols have been developed which seek to provide quarantine assurance to lucrative export markets. Hot Water Treatment technology has several advantages over other conventional phytosanitary treatments. It provides a triple function of cleaning, disinfesting, and disinfecting and is friendly to users, consumers of the treated commodities, and the environment. We discuss HWT in the context of its future and applicability in Africa. It is the future of postharvest treatments.

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Effect of hot-water immersion on eggs and larvae of Anastrepha grandis (Macquart, 1846) (Diptera: Tephritidae) “in vitro” and on squash (Cucurbita moschata Duchesne, 1786)

REVISTA CHILENA DE ENTOMOLOGÍA ◽

10.35249/rche.47.4.21.01 ◽

2021 ◽

Vol 47 (4) ◽

pp. 653-668

Author(s):

Fernando Berton Baldo ◽

Adalton Raga

Keyword(s):

Water Treatment ◽

Hydrothermal Treatment ◽

Water Immersion ◽

Fruit Fly ◽

Hot Water ◽

Hot Water Treatment ◽

Cucurbita Moschata ◽

Phytosanitary Treatment ◽

Eggs And Larvae

There are risks involved in the production and exportation of fruit fly hosts due to the possible spread of tephritid pests during distribution. Anastrepha grandis attacks cucurbit fruits and is considered an A1 quarantine pest in many countries. The objective of this study was to evaluate the effect of hot water treatment on the eggs and larvae of A. grandis in vitro, and on ‘Atlas’ squash (Cucurbita moschata). The eggs and third-instar larvae of A. grandis were exposed to hot water at temperatures of 42.0, 44.0, 46.0, 46.5, 47.0, 47.5, 48.0, 49.0 and 50.0 (± 0.5) °C for durations of 0 (control), 10, 20, 30 and 60 minutes. Water temperatures of at least 44 °C affected the in vitro larval eclosion of A. grandis during all exposure times. No adults were obtained when in vitro A. grandis larvae were treated at 49 °C and 50 °C at all exposure times and, 48 °C for 30 and 60 minutes. No adults were obtained when squashes infested with A. grandis eggs or larvae were treated at temperatures of 49 °C and 50 °C during any exposure time, as well as subjected to 48 °C for 20 minutes. Anastrepha grandis larvae were slightly more susceptible to hydrothermal treatment than eggs in squashes. Hot water treatment applies at a temperature of 48 °C for 20 minutes is an effective phytosanitary treatment for squashes cv. Atlas infested with eggs and larvae of A. grandis.

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EFFECT OF HOT-WATER TREATMENT IN THE MORTALITY OF FRUIT FLY EGGS

Acta Horticulturae ◽

10.17660/actahortic.2010.877.209 ◽

2010 ◽

pp. 1525-1528

Author(s):

S.M.J. Vieira ◽

B.C. Benedetti ◽

A. Raga ◽

M.F. Souza Filho

Keyword(s):

Water Treatment ◽

Fruit Fly ◽

Hot Water ◽

Hot Water Treatment

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Conditioning with hot air reduces heat damage caused to 'Kensington' mango (Mangifera indica Linn.) by hot water disinfestation treatment

Australian Journal of Experimental Agriculture ◽

10.1071/ea9960507 ◽

1996 ◽

Vol 36 (4) ◽

pp. 507 ◽

Cited By ~ 7

Author(s):

KK Jacobi ◽

LS Wong ◽

JE Giles

Keyword(s):

Water Treatment ◽

Mangifera Indica ◽

Cost Effective ◽

Fruit Fly ◽

Hot Water ◽

Hot Water Treatment ◽

Hot Air ◽

Commercial Scale ◽

Cost Effective Method ◽

Internal Cavities

Hot water treatment (HWT) offers a cost-effective method for fruit fly disinfestation but may cause injury to 'Kensington' mango (Mangifera indica Linn.). Conditioning fruit with hot air before disinfestation may alleviate these injuries. Fruit from 2 major production regions in Queensland were subjected to conditioning treatments with hot air (38-40�C) for 0, 4,8, 12, and 16 h before HWT (fruit core temperature of 45�C held for 30 min). Injuries to fruit not conditioned before HWT included accentuated lenticel spotting, external and internal cavities, and a starchy layer beneath the skin. Fruit conditioned for 8 or 12 h before HWT had minimal injuries. Conditioning with hot air before HWT has the potential to minimise and/or eliminate heat injuries associated with hot water disinfestation treatment. Further testing, particularly on a commercial scale, will be required to optimise these conditioning treatments for use by the Australian mango industry.

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