On this page
Quick answer
A banana ripening chamber ripens green bananas in 4–6 days by pre-cooling fruit to 14–16°C, then dosing pure ethylene at 100–150 ppm for 18–24 hours at 15–18°C and 90–95% RH with continuous CO₂ scrubbing. A single 5 MT chamber costs about ₹6–9 lakh and a 6-chamber, 30 MT facility ₹55–70 lakh. FSSAI bans calcium carbide ripening.
Key takeaways
- Chamber sizes run from 18–22 m² for 4–5 MT per cycle to 90–110 m² for 24–30 MT per cycle.
- For 30 MT of daily dispatch, 6 medium chambers run in rotation so that one completes ripening every day.
- A 5 MT chamber uses a 4–5 TR Daikin scroll unit, a 2,500–4,000 CFM centrifugal fan and 100mm gas-tight PUF panels.
- On a job-work model, a 30 MT facility processing 144 MT a month at ₹3.50/kg earns about ₹60 lakh a year and pays back in about 20 months.
- Backup power is essential, because a single 6-hour outage can damage an entire batch.
Why Ripening Chambers Exist
Banana is a climacteric fruit — it produces ethylene as it ripens. Bananas are harvested green, transported under cool conditions, then deliberately ripened through controlled ethylene exposure.
The traditional alternative — calcium carbide on a shed floor — produces uneven ripening, off-flavours, acetylene gas residues (banned by FSSAI), and health risks. A modern ripening chamber uses pure ethylene at 100–150 ppm for uniform, market-ready fruit with no chemical residues.
The 4-Day Ripening Cycle
Day 0 — Pre-cooling: Green bananas arrive. Chamber pre-cools fruit to 14–16°C over 4–6 hours.
Day 1 — Gassing: Ethylene at 100–150 ppm. Temperature 15–18°C. Humidity 90–95%. CO₂ scrubbed continuously. Duration: 18–24 hours.
Day 2 — Colour break: Ethylene flushed. Fresh air introduced. First yellow patches appear at tips.
Day 3 — Yellowing: Hold at 14–17°C. Bananas progress to mostly yellow.
Day 4 — Market ready: Full yellow with slight green at tips. Dispatch to retail.
Chamber Sizing
| Size | Floor area | Crates/cycle | MT/cycle |
|---|---|---|---|
| Small | 18–22 m² | 200–250 | 4–5 MT |
| Medium | 32–40 m² | 400–500 | 8–10 MT |
| Large | 55–70 m² | 700–850 | 14–17 MT |
| Industrial | 90–110 m² | 1,200–1,500 | 24–30 MT |
For 30 MT daily dispatch: 6 medium chambers in rotation (one ripening every day).
Equipment Specification (5 MT Chamber)
Refrigeration: Daikin scroll ODU 4–5 TR, indoor evaporator with EC fans, R32/R410A, EEV.
Humidification: Ultrasonic 4–6 kg/hour in supply duct.
Air handling: Centrifugal fan 2,500–4,000 CFM, motorised fresh air and exhaust dampers, ductwork for uniform velocity (3–5 m/s).
Ethylene: Medical-grade cylinder with mass flow controller, over-feed protection.
CO₂ scrubber: Lime or activated carbon.
Sensors: 2 temperature, 1 humidity, 1 CO₂, 1 ethylene analyser, PLC/BMS, HMI touchscreen, remote alarm.
Construction: 100mm PUF panels (gas-tight), 3.0–3.5m ceiling.
Capex Breakdown
Single 5 MT chamber: ₹6.1–9.1 lakh
6-chamber facility (30 MT):
- Chambers: ₹45 lakh
- Shared utilities (DG, water, HT): ₹6 lakh
- Civil work: ₹8 lakh
- Common equipment: ₹4 lakh
- Total: ₹63 lakh
100 MT industrial (10 chambers):
- Chambers: ₹95 lakh
- Shared utilities: ₹14 lakh
- Civil: ₹16 lakh
- Total: ₹1.33 crore
ROI Math — 30 MT Facility
Job-work model: 144 MT/month processed × ₹3.50/kg = ₹60 lakh/year revenue. OpEx: ₹22 lakh/year. EBITDA: ₹38 lakh/year. Payback: ~20 months.
Own-account model: Buy green at ₹26/kg, sell ripe at ₹38–42/kg. Margin ~₹10/kg after 4% wastage. Higher returns but requires ₹40–60 lakh working capital.
Most facilities run a hybrid: own-account for major customers, job-work for spare capacity.
Common Mistakes
- Cheap construction with leaky doors — ethylene escapes, uneven ripening
- Shared chambers with normal cold storage — fundamentally different conditions
- No CO₂ scrubbing — off-flavours from high CO₂
- Wrong air velocity — too low: uneven; too high: dehydration
- Underpowered humidification — can't hold 90–95% RH
- Manual ethylene dosing — inconsistent concentrations
- No backup power — single 6-hour outage damages entire batch
FAQ
Frequently asked questions
How much does a banana ripening chamber cost in India?
A single 5 MT chamber costs ₹6–9 lakh. A 30 MT facility (6 chambers) runs ₹55–70 lakh. A 100 MT industrial facility costs ₹1.2–1.5 crore.
How long does it take to ripen bananas in a chamber?
4–6 days for a complete cycle: pre-cool, gas, colour break, yellowing, market-ready.
Is calcium carbide ripening legal in India?
No. Calcium carbide is banned under FSSAI Regulation. Ethylene generators or pure ethylene gas are the legal alternatives.
Do banana ripening chambers qualify for NHB subsidy?
Yes. Eligible under NHB at 35% capital subsidy (50% for NE states).
Written by
HyperCold Engineering Team
Cold room and cold storage engineers at HyperCold™, a Daikin equipment partner founded in 2020 and headquartered in Sirsaganj, Firozabad (UP). We design, manufacture PUF panels for, install and maintain cold rooms across India.