Reponses of some tropical fruits to insecticidal atmospheres.
Yahia E. M.
Author Affiliation: Centro de Investigación en Alimentación y Desarrollo, Hermosillo, Sonora, Mexico.
: 371-376
Abstract : Physiological and biochemical responses of mango (cv. Keitt), pawpaw (cv. Sunrise) and avocado (cv. Hass) fruits to atmospheres that have potential as insect quarantine treatments (?0.5% O2 and ?50% CO2) were evaluated. Samples of fruits were evaluated for enzyme activity, respiration rate, flesh firmness, external appearance, internal quality and sensory properties. Avocado fruits were very sensitive, mango fruits were very tolerant and pawpaw fruits were intermediate in their level of tolerance to such extreme atmospheres. Insecticidal atmospheres resulted in changes in glycolytic and tricarboxylic acid cycle activities and slightly increased alcohol dehydrogenase and pyruvate decarboxylase (PDC) activities in mango fruits but caused no fruit injury or detrimental sensory changes after exposure for up to 5 days. Pawpaw fruits developed decay and off-flavours and had increased PDC and lactate dehydrogenase activity after 2 days. Avocados developed injury, had increased production of ethanol and acetaldehyde, had increased activity of anaerobic enzymes and decreased concentration of 3 glycolytic intermediates after one day of exposure to these atmospheres.