1) What are the thermal properties of carrots?
- Specific heat above freezing: 3.92 kJ/kg.K
- Specific heat below freezing: 2.00 kJ/kg.K
- Latent heat of fusion: 293 kJ/kg
2) What is the storage condition for carrots?
a) Fresh:
Storage temperature: 0 °C
Relative Humidity: Topped - 98 to 100%, Bunched – 95 to 98%
Storage life: Mature topped-5 to 9 months, Immature topped – 4 to 6 weeks, Bunched-8 to 12 days
b) Frozen:
Frozen temperature: -18 °C
Relative Humidity: vapor tight packing
Storage life: 1 year +
3) How to store mature topped carrots?
a) After harvest, mature topped carrots should keep at 0 °C cooled to this storage temperature and the life time will be 5 to 9 months
b) Recommended RH is 98 -100% to minimize moisture loss, writing, and decay
c) Air circulation required for between the pallets to remove respiration heat and maintain uniform room temperature
d) Storage in plastic film reduces the weight loss but may increased decay
4) What are the practices for storing of immature carrots?
a) During cooling of immature carrots, hydro-cooling with chlorinated water to reduce the root temperature below 5 °C
b) Storage at high relative humidity of 98-100% is to reduce water loss and loss of crispness
c) It can be stored at 0 °C for the period of 4 to 6 weeks
d) Carrots are packed in polyethylene bags or in cartons
5) How to store bunched carrots?
a) Bunched carrots are stored 8 to 12 days at 0 °C storage temperature
b) Package ice used in containers of bunched carrots to reduce water loss and quality during shipment
c) Prevent storage of carrots from ethylene produce products like some other vegetables
6) Why we are not recommended storage of carrots in Controlled Atmosphere (CA)?
If we store carrots in Controlled Atmosphere (CA,) concentration of o2 less than 3% and concentration of Co2 greater than 5% promote decay.
7) How to store peeled or cut carrots?
a) For storing of peeled carrots, we should maintain atmosphere of 2 to 5% o2 and 15 to 20% Co2
b) Preserve the quality of carrots maintained up to 14 days at 2 °C cold room temperature.
8) List out the diseases and injuries of carrots during cold storage?
a) Bacterial soft rot
b) Black rot
c) Fusarium rot
d) Graymold rot
e) Rhizoctonia crown rot
f) Watery soft rot
g) Freezing injury
9) How to freeze the carrots?
a) First carrots should be peeled to remove the skin by using steam then washed, brushed, or scratched off
b) They are sliced and blanched in boiling water for 3 to 5 minutes
c) Frozen the carrots by using IQF system
10) How to handle the carrots in cold storage?
Carrots in the frozen state are not sensitive to fluctuation of temperature and then if it is thawed and refrozen, the quality of firmness will loose.
