HOT WATER TREATMENTS FOR THE POSTHARVEST CONTROL OF FRUIT FLY AND ANTHRACNOSE IN THE CARIBBEAN MANGO 'JULIE'

Breadfruit from Samoa potentially host the Pacific fruit fly (Bactrocera xanthodes) and so their export to New Zealand requires a disinfestation treatment. Heat treatments by air (HAT) or water (HWT) are common fruit-fly disinfestation treatments for tropical crops. Two breadfruit cultivars – Puou and Ma’afala – were subjected to three heat treatments, HAT-1 (minimum 47.2oC for 20 min at core), HAT-2 (49.0oC for 100 min at core) and HWT (47.2oC for 20 min at core), and an untreated control was also included. Fruit were stored for one week at 15oC followed by three days at 25oC. Disorders observed were heat damage to the skin (blackening) and increased decay on the body and stem-end. Heat damage was at an acceptably low level following HAT-1 but was unacceptable following HAT-2 or HWT. Initial results suggest that a HAT can be tolerated, but the effect of ramp rate and the potential of using a two-step HWT system should be examined.

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Effects of microwave-assisted hot water treatments designed against Mexican fruit fly (Anastrepha ludens ) on grapefruit (Citrus paradisi ) quality

Journal of the Science of Food and Agriculture ◽

10.1002/jsfa.8844 ◽

2018 ◽

Vol 98 (10) ◽

pp. 3659-3666 ◽

Cited By ~ 3

Author(s):

Nohemi Soto-Reyes ◽

Aurelio López-Malo ◽

Roberto Rojas-Laguna ◽

Julián Andrés Gómez-Salazar ◽

María Elena Sosa-Morales

Keyword(s):

Fruit Fly ◽

Hot Water ◽

Anastrepha Ludens ◽

Citrus Paradisi ◽

Mexican Fruit Fly ◽

Microwave Assisted ◽

Water Treatments

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Commodity Heating Medium and Mexican Fruit Fly Mortality

HortScience ◽

10.21273/hortsci.33.3.533e ◽

1998 ◽

Vol 33 (3) ◽

pp. 533e-533

Author(s):

Krista C. Shellie

Keyword(s):

Carbon Dioxide ◽

Variable Temperature ◽

Larval Mortality ◽

Fruit Fly ◽

Hot Water ◽

Water Bath ◽

Controlled Atmosphere ◽

Mexican Fruit Fly ◽

Temperature Water ◽

Heating Medium

The objective of this research was to investigate whether the medium used to transfer heat to a commodity influenced the mortality of Mexican fruit fly larvae. A similar 2-h heat dose was delivered to grapefruit via immersion in a variable temperature water bath or via exposure to a rapidly circulating gas. The concentration of oxygen and carbon dioxide inside the grapefruit was analyzed at 30-min intervals and grapefruit center temperatures recorded every 60 s during heating. The mortality of larvae located inside grapefruit during heating in a controlled atmosphere or in hot water was significantly higher than that of larvae located inside grapefruit heated in air. The internal atmosphere of grapefruit heated in a controlled atmosphere or in hot water contained significantly higher levels of carbon dioxide and lower levels of oxygen than grapefruit heated in air. Larval mortality was compared after larvae were heated in media by rapidly circulating air or by an atmosphere containing 4 kPa of oxygen and 18 kPa of carbon dioxide to evaluate whether the altered atmosphere or a heat-induced fruit metabolite was responsible for enhanced mortality. The significantly higher mortality of larvae heated in media in the presence of an altered atmosphere suggested that the altered atmosphere enhanced larval mortality. Results from this research suggest that reducing oxygen and or increasing the level of carbon dioxide during heating can enhance mortality of the Mexican fruit fly and potentially reduce the heat dose required for quarantine security.

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Alfa fibers for Cereplast bio-composites reinforcement: Effects of chemical and biological treatments on the mechanical properties

Polymers and Polymer Composites ◽

10.1177/09673911211006067 ◽

2021 ◽

pp. 096739112110060

Author(s):

Mouna Werchefani ◽

Catherine Lacoste ◽

Hafedh Belguith ◽

Chedly Bradai

Keyword(s):

Charpy Impact ◽

Impact Testing ◽

Hot Water ◽

Cellulose Content ◽

Twin Screw ◽

Electron Microscopy Analysis ◽

Alfa Fibers ◽

Charpy Impact Testing ◽

Water Treatments ◽

The Impact

The present work is a comparative study of the impact of Alfa fiber modifications on the Cereplast composites mechanical behavior. Various treatments have been employed, including mechanical, soda, saltwater-retting, hot-water treatments and enzymatic treatment using xylanase. Chemical and morphological analyses were carried out in order to determine the changes of the biochemical composition and the dimensions of fibers. Cereplast composites reinforced with Alfa fibers were fabricated using a twin-screw extrusion followed by an injection molding technique with a fiber load of 20 wt. %. Resulting materials were assessed by means of tensile, flexural and Charpy impact testing. Scanning Electron Microscopy analysis was carried out to investigate the interfacial properties of the composites. The results have shown a significant enhancement of mechanical strengths and rigidities for the xylanase-treated fiber composites, owing to the increase of cellulose content, the enhancement of defibrillation level and the improvement of matrix-fiber adhesion. The data proved that the technology of enzymes can be used as a powerful and eco-friendly approach to modify fiber surfaces and to increase their potential of reinforcement.

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