Postharvest heat and cold treatment to control Ceratitis capitata on cactus pear fruit.
In order to work out a quarantine treatment for cactus pear fruit a factorial experimental plan was carried combining postharvest water dips at 20, 50, 54, 58 and 60 degrees C and storage at 1 degrees C for 3, 6 and 10 days. Cactus pear fruit cv 'Rossa' were artificially infested with Med. fly eggs (at least 20 eggs per fruit) then left in the lab at 25 degrees C for 4 days. Treatments took place by dipping the fruit at each water temperature for 2 mm. At each established time fruit was picked and checked for vital larvae and degree of chilling injury (CI). Probit 9 requirements were achieved in all cases when fruit was cold-stored for 10 days. When fruit was kept for 6 days the quarantine requirement was achieved only by dipping the fruit at 58 and 60 degrees C while none dip treatment was effective if fruit was stored for 3 days at 1 degrees C. All Fruit stored for 10 days at 1 degrees C showed severe CI symptoms and when kept for 6 days the same degree of CI was found on fruit dipped in water at 20, 58 and 60 degrees C. No CI was observed after 3 days at 1 degrees C. In conclusion only when fruit was dipped at 50-54 degrees C and stored for 10 days at 1 degrees C the probit 9 condition was attained with acceptable CI symptoms.
D'Hallewin
G
G
ISPA-CNR Sezione di Sassari, Via Dei Mille 48, 1-07100 Sassari, Italy. Guy.dhallewin@ispa.cnr.it
Venditti
T
T
Molinu
M G
MG
Dore
A
A
Serusi
A
A
D000818:Animals; D033622:Ceratitis capitata / Q000254:growth & development*; D003080:Cold Temperature; D005511:Food Handling / Q000379:methods*; D005519:Food Preservation / Q000379:methods*; D006358:Hot Temperature; D029747:Opuntia / Q000469:parasitology*; D013997:Time Factors