Pawpaw

Recomendaciones para mantener la calidad poscosecha

Índices de madurez

Índices de madurez

Pawpaw (Asimina triloba; family Annonaceace) is the largest edible fruit native to the eastern U.S. The fruit ripens between mid August and mid October, depending on genotypes and growing location.

The only way to detect if ripening has commenced is to gently press or squeeze the fruit to determine if softening is evident. Some cultivars exhibit a change in skin color from darker to lighter green or even to yellow, and some also exhibit some skin browning or darkening at more advanced stages of ripening. Flesh may be cream-colored, yellow, or light orange, depending on cultivar, when fully ripe. Ripening is accompanied by an increase in soluble solids including sugars (sweetness) and significant aroma production. Pawpaws should be picked when flesh softening is first evident, as they ripen rapidly and become too soft to handle within 3 to 5 days.

Índices de calidad
  • Green to yellowish-green skin, firm fruits with minimal brown discoloration on the skin.
  • Soft, custard-like flesh
  • Sweetness (glucose, fructose and sucrose) at >18-20% soluble solids
  • Intense aroma reminiscent of banana, mango, and/or pineapple.
  • Free of bruises and decay
Temperatura óptima

0-4°C (32-40°F) for a maximum of 4 weeks

Lower temperatures within this range and especially longer periods of cold storage may induce chilling injury.

Tasa de respiración

Respiration at harvest may be 50-100 mg CO2/ kg•hr at 20°C (68°F), and may increase 2- to 5-fold to a peak within 3 days.

Respuestas al etileno

Field and laboratory studies to date using chemicals, atmospheric modification, or heat treatments that have been effective at modifying ripening behavior in many climacteric species via effects on ethylene biosynthesis or action have failed to appreciably alter ripening of pawpaw.

Humedad relativa óptima

90-95%

Tasa de producción de etileno

Ethylene production at harvest may be 1-4 µg/kg•hr at 20°C (68°F), and it may increase to 5-15 µg/kg•hr within 3 days.

Pawpaw exhibits increasing respiration and ethylene production with peak values within 3 days after harvest indicating it is a climacteric fruit.

Respuestas a la atmósfera controlada (AC)

There is no information on their response to CA storage.

 Temperature & Controlled Atmosphere Photos

1pawpawHarvestIntact

Title: Pawpaw genotype #8 20 Intact at Harvest

Photo Credit: Federica Galli, University of Kentucky, Lexington

3pawpawHarvestXSection2

Title: Storage Effects, X-Cut at Harvest

Photo Credit: Federica Galli, University of Kentucky, Lexington

10pawpawAfter4weeks4C_72hIntact

Title: Storage Effects, Intact at 4 weeks + 72 hrs 4°C

Photo Credit: Federica Galli, University of Kentucky, Lexington

8pawpawAfter4Weeks4CIntact

Title: Storage Effects, Intact at 4 weeks 4°C

Photo Credit: Federica Galli, University of Kentucky, Lexington

14pawpawAfter8Weeks4C_72hIntact

Title: Storage Effects, Intact at 8 weeks + 72 Hrs 4°C

Photo Credit: Federica Galli, University of Kentucky, Lexington

12pawpawAfter8Weeks4CIntact

Title: Storage Effects, Intact at 8 weeks 4°C

Photo Credit: Federica Galli, University of Kentucky, Lexington

11pawpawAfter4Weeks4C_72hXSection

Title: Storage Effects, X-Cut at 4 weeks + 72 hrs 4°C

Photo Credit: Federica Galli, University of Kentucky, Lexington

9pawpawAfter4Weeks4CXSection

Title: Storage Effects, X-Cut at 4 weeks 4°C

Photo Credit: Federica Galli, University of Kentucky, Lexington

15pawpawAfter8Weeks4C_72hXSection

Title: Storage Effects, X-Cut at 8 weeks + 72 Hrs 4°C

Photo Credit: Federica Galli, University of Kentucky, Lexington

13pawpawAfter8Weeks4CXSection

Title: Storage Effects, X-Cut at 8 weeks 4°C

Photo Credit: Federica Galli, University of Kentucky, Lexington

   
Fisiopatías y daños físicos

Chilling Injury. Both skin and internal flesh browning of pawpaw have been observed by 6 weeks at 0-4°C (32-40°F).

Physical Injury. Similar to wound-induced browning in banana, pawpaws can be bruised during ripening. Thus, gentle handling to minimize bruising is essential to reducing postharvest losses.

Shriveling. Symptoms become visible by 6 weeks of cold storage.

Enfermedades

Postharvest diseases of pawpaws from Cladosporium spp. and Fusarium spp. have been observed by 6 weeks of 0-4°C (32-40°F) storage.