MATURITY & QUALITY
Maturity Indices
Fresh market figs must be harvested when almost fully ripe to be of good eating quality. Skin color and flesh firmness are dependable maturity and ripeness indices ‘Black Mission’ figs should be light to dark purple rather than black and should yield to slight pressure. ‘Calimyrna’ figs should be yellowish-white to light yellow and firm.
Quality Indices
Fresh figs’ skin color and flesh firmness are related to their quality and postharvest-life. Flavor is influenced by stage of ripeness and overripe figs can become undesirable due to fermentative products. Other quality indices include absence of defects (such as bird-peck, sunburn, scab, skin break, and stem shrivel), insects, and decay.
TEMPERATURE & CONTROLLED ATMOSPHERE (CA)
Optimum Temperature
-1°C to 0°C (30°F to 32°F)
Expedited forced-air cooling to 0°C (32°F) is strongly recommended.
Optimum Relative Humidity
90-95%
Rates of Respiration Production
| Temperature | ml CO2/ kg·hr | |
| °C | °F | |
| 0 | 32 | 2-4 |
| 5 | 41 | 5-8 |
| 10 | 50 | 9-12 |
| 20 | 68 | 20-3 |
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
| Temperature | 0°C(32°F) | 5°C(41°F) | 10°C(50°F) | 20°C(68°F) |
| ul C2H4/kg·hr | 0.4-0.8 | 0.8-1.5 | 1.5-3.0 | 4.0-6.0 |
Responses to Ethylene
Figs are slightly sensitive to ethylene action on stimulating softening and decay severity, especially if kept at 5°C (41°F) or higher temperatures.
Responses to Controlled Atmospheres (CA)
CA combinations of 5-10% oxygen and 15-20% carbon dioxide are effective in decay control, firmness retention, and reduction of respiration and ethylene production rates. Postharvest-life at optimum temperature and relative humidity depends upon cultivar and ripeness stage at harvest and ranges from 1 to 2 weeks in air and from 3 to 4 weeks in CA for California-grown ‘Black Mission’ and ‘Calimyrna” figs.
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