Lemon
Maturity Indices
A minimum juice content by volume of 28 or 30% depending on grade; color Lemon picked at the dark-green stage have the longest postharvest life while those picked fully-yellow must be marketed more rapidly.
Quality Indices
Yellow color intensity and uniformity; size; shape; smoothness; firmness; freedom from decay; and freedom from defects including freezing damage, drying, mechanical damage, rind stains, red blotch, shriveling, and discoloration.
Lemon Optimum Temperature
12-14°C (54-57°F) depending on cultivar, maturity-ripeness stage at harvest, production area, and duration of storage and transport (can be up to 6 months).
Optimum Relative Humidity
90-95%
Rates of Respiration
Temperature | 10°C (50°F) | 15° (59°F) | 20° (68°F) |
ml CO2/ kg·hr | 5-6 | 7-12 | 10-14 |
To calculate 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
< 0.1 µl/kg·hr at 20°C (68°F)
Responses to Ethylene
If degreeing is desired, lemons can be treated with 1-10 ppm ethylene for 1-3 days at 20 to 25°C (68-77°F), but this exposure may accelerate deterioration rate and decay incidence
Responses to Controlled Atmospheres (CA)
CA of 5-10% O2 and 0-10% CO2 can delay senescence including loss of green color of lemons. Fungistatic CO2 levels (10-15% are not used because they may induce off-flavors due to accumulation of fermentative volatiles, especially if O2levels are below 5%. Removal of ethylene from lemon storage facilities can reduce rate of senescence and decay incidence.