Bell Pepper
Recommendations for Maintaining Postharvest Quality
 Marita Cantwell Department
of Vegetable Crops, University of California, Davis, CA 95616
Maturity Indices
Green Peppers: fruit
size, firmness, color Colored Peppers: minimum 50% coloration
Quality Indices * Uniform
shape, size and color typical of variety * Firmness * Freedom from defects
such as cracks, decay, sunburn
Optimum Temperature
Peppers should be cooled as soon as possible to reduce water loss. Peppers
stored above 7.5°C (45°F) suffer more water loss and shrivel. Storage at
7.5°C (45°F) is best for maximum shelf-life (3-5 weeks); peppers can be
stored at 5°C (41°F) for 2 weeks, and although this reduces water loss,
chilling injury will begin to appear after that period. Symptoms of chilling
injury include pitting, decay, discoloration of the seed cavity, softening
without water loss. Ripe or colored peppers are less chilling sensitive
than green peppers.
Optimum Relative > 95%; firmness of peppers is directly related to water loss
Rates of Respiration Temperature 5°C(41°F) 10°C(50°F) 20°C(68°F) ml
CO2/kg·hr 3-4 5-8 18-20 To calcualte heat production multiply ml CO2/kg·hr
by 440 to get BTU/ton/ day or by 122 to get kcal/metric ton/day.
Rates of Ethylene Production Bell peppers are nonclimacteric in behaviour
and produce very low levels of ethylene: 0.1-0.2 µl/kg·hr at 10°-20°C (50°-68°F).
Responses to Ethylene Bell Peppers respond very little to ethylene; to accelerate
ripening or color change, holding partially colored peppers at warm temperatures
of 20-25°C (68-77°F) with high humidity (>95%) is most effective.
Responses to Controlled Atmospheres (CA) Peppers generally do not respond
well to CA. Low O2 atmospheres (2-5% O2) alone have little effect on quality
and high CO2 atmospheres (>5%) can damage peppers (pitting, discoloration,
softening) especially if they are stored below 10°C (50°F). Atmospheres
of 3% O2+ 5% CO2were more beneficial for red than green peppers stored at
5°C (41°F) to 10°C (50°F) for 3-4 weeks. -------------------------
Physiological Disorders Blossom end rot. this disorder occurs as a slight
discoloration or a severe dark sunken lesion at the blossom end; it is caused
by temporary insufficiencies of water and calcium and may occur under high
temperature conditions when the peppers are rapidly growing. Pepper speck.
this disorder appears as spot-like lesions that penetrate the fruit wall;
cause is unknown; some varieties are more susceptible than others. Chilling
injury. symptoms of chilling injury include surface pitting, water-soaked
areas, decay (especially Alternaria), and discoloration of the seed cavity.
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Pathological Disorders On California-grown bell peppers, the most common
decay organisms are Botrytis, Alternaria, and soft rots of fungal and bacterial
origin. Botrytis or Grey mold decay. this is a common decay-causing organism
on peppers; field sanitation and prevention of wounds on the fruit help
reduce its incidence. Botrytis will grow well at the recommended storage
temperatures. High CO2levels (>10%) which can control Botrytis damage peppers.
Hot water dips of peppers can effectively control botrytis rot ( 55°C [130°F]
water for 4 minutes) without causing fruit injury. Alternaria rot. the presence
of black Altenaria rot, especially on the stem end of the pepper is a symptom
of chilling injury; best control measure is to store at 7.2°C (45°F) Bacterial
Soft Rot. soft rotting areas can be caused by several bacteria which attack
damaged tissue; soft rots can also common on washed or hydrocooled peppers
where water sanitation was deficient ------------------------------------------------------------------------
Other Commonn Postharvest Defects Mechanical damage (crushing, stem punctures,
cracks, etc.) is very common on peppers; physical injury not only detracts
from the visual quality of the peppers but also causes increased weight
loss and decay.
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