Apple Golden Delicious
Maturity Indices
Apple Golden Delicious Color change from dark green to light green or yellowish-green. Firmness of 17 pounds-force, 20 to 40% of cortex clear of starch. Generally about 135 to 150 days from full bloom.
Quality Indices
- Firmness, crispness, lack of mealiness <>LI> Flavor, including soluble solids, titratable acidity and flavor volatiles.
- Freedom from defects such as bruising, decay, stem or blossom-end cracks, bitter pit, scald, internal browning, or shrivel.
Apple Golden Delicious Optimum Temperature
0°C ± 1°C (32°F ± 2°F); Freezing temperature: -1.7°C (29°F)
Optimum Relative Humidity Optimum Relative Humidity
90-95% RH
Rates of Respiration
Temperature | 0°C (32°F) | 5°C (41°F) | 10°C (50°F) | 20°C (68°F) |
ml CO2/ kg·hr | 3-6 | 4-8 | 7-12 | 15-30 |
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.
Higher rates for riper apples.
Rates of Ethylene Production
Temperature | 0°C (32°F) | 5°C (41°F) | 10°C (50°F) | 20°C (68°F) |
µl/ kg·hr | 1-10 | 2-25 | 5-60 | 20-150 |
Higher rates for riper apples.
Responses to Ethylene
Ethylene stimulates ripening. Mixed results on the benefits of scrubbing ethylene from storage rooms, depending on harvest maturity, and duration and type of storage (air or CA).
Responses to Controlled Atmospheres (CA)
Fruit to be stored longer than one month benefit from CA storage in terms of retention of flesh firmness, acidity, and skin color. CA storage potential is up to 10 months (vs. 6 months in air).
Recommended atmospheres: 1 to 3% O 2 + 1.5 to 3% CO2