Post-harvest management of horticultural crops

Horticulture (B.Sc Horticulture) · Practices · free study notes for exams, placements and interviews

In short

Post-harvest management covers every operation applied to a horticultural crop from the moment of harvest until it reaches the consumer - harvesting at the right maturity, pre-cooling, cleaning, sorting, grading, treatment, packaging, storage, transport and ripening. It matters because fruits and vegetables are living, respiring, highly perishable tissues with 75-95% moisture, and India's post-harvest losses in horticulture run to roughly 4-16% by quantity depending on crop (CIPHET 2015 study), worth tens of thousands of crores annually. The subject is examined in B.Sc Horticulture post-harvest technology papers, ICAR JRF/SRF and ASRB NET, and is the core technical round for jobs in cold chain, agri-export, food processing and retail sourcing. Employers test maturity indices, respiration and ethylene behaviour, storage conditions crop by crop, packaging choices and the MIDH/NHB/APEDA/FSSAI framework a graduate must work inside.

Explained

Nature of the produce and causes of loss

Harvested produce is still alive: it respires (consumes O₂, releases CO₂, heat and water), transpires and, in fruits, ripens and senesces. It cannot add photosynthate, so it lives on stored reserves - every hour at high temperature is reserve burnt and shelf life lost.
Respiration rate (mg CO₂ kg⁻¹ h⁻¹ at 5 °C) classifies produce: very low (nuts, dates), low (apple, grape, potato, onion, citrus), moderate (banana, mango, tomato, carrot, cabbage), high (strawberry, cauliflower, bean), very high (asparagus, mushroom, spinach, broccoli, pea, sweet corn). High respiration = short life.
Q₁₀ effect: respiration roughly doubles to quadruples for every 10 °C rise; so temperature is the single most powerful control variable.
Water loss (transpiration): driven by vapour pressure deficit (VPD); 5-10% weight loss causes visible wilting and unsaleability. Controlled by low temperature + high RH (85-95%) + waxing/liners.
Loss categories: physiological (respiration, ripening, sprouting, chilling injury, internal breakdown), pathological (*Colletotrichum* anthracnose in mango, *Penicillium* green/blue mould in citrus, *Botrytis* grey mould in grape, *Rhizopus* in stone fruit), mechanical (impact, compression, vibration/abrasion in transit), and insect/rodent.
Mechanical injury is the gateway: bruises raise respiration and ethylene locally and open the wound to rot. Hence crates, not gunny bags, and ≤4-5 layers deep.

Maturity, harvesting and maturity indices

Physiological maturity: stage at which the organ will complete development and ripen normally after detachment. Horticultural (commercial) maturity: stage at which it is required for its intended use - may be immature (okra, cucumber, baby corn), mature (mango for ripening), or ripe (grape, strawberry).
Climacteric fruits ripen after harvest with a respiration and ethylene peak: mango, banana, papaya, guava, sapota, tomato, apple, pear, custard apple, passion fruit. Harvested mature-unripe for transport.
Non-climacteric fruits do not ripen off the plant: grape, citrus, litchi, pineapple, pomegranate, strawberry, cashew apple, ber. Must be harvested at eating ripeness.
Maturity indices used in India:
- Days from fruit set / full bloom (mango 90-120 days by variety; apple 135-150).
- Specific gravity / float test - mango (sinks in 1% salt solution), watermelon.
- TSS (°Brix) by hand refractometer - grape ≥16 °Brix for table, sapota, pineapple; TSS:acid ratio for citrus (Kinnow ~12:1) and mango.
- Firmness by penetrometer (kgf or N) - apple ~6.8 kg with 11 mm plunger; starch-iodine test for apple.
- Skin and flesh colour, ground colour change, shoulder development (mango), waxy bloom, drying of the tendril (watermelon), easy separation/abscission, shrivelling of the pedicel.
- Size, shape, aroma, dryness of top leaves (onion neck fall 50-70%), curd compactness (cauliflower), tenderness (pea - tenderometer).
Harvest practice: harvest in the cool morning, avoid rain-wet produce, use a mango harvester with a pedicel-retaining net, retain 5-10 mm pedicel in mango to avoid sap burn, de-sap by inverting fruit on a mesh, clip (not pull) grape bunches and pomegranate, use picking bags/field crates, keep harvested produce under shade immediately.

Post-harvest operations - the step sequence

Pre-cooling - removing field heat within hours; the most important single step. Methods: room cooling (slow), forced-air (pressure) cooling (most common for fruits, 1-6 h), hydro-cooling (water, for carrot, leafy, stone fruit), vacuum cooling (fastest for leafy vegetables, mushroom - exploits evaporation at low pressure), package icing (broccoli, leafy), evaporative cooling (low-cost). 7/8 cooling time = time to remove 7/8 of the difference between initial and medium temperature; roughly 3 × the half-cooling time.
Cleaning and washing - potable water; chlorinated water 50-200 ppm available chlorine or 100 ppm sodium hypochlorite as a sanitiser (not a fungicide); brush-roller washers; drying before packing.
Sorting - removal of diseased, damaged, over/under-mature, misshapen units.
Grading - separation into quality classes by size, weight, colour, freedom from blemish; manual, screen/roller sizers, weight graders, electronic/optical graders. Agmark grade standards (Directorate of Marketing & Inspection, under the Agricultural Produce (Grading and Marking) Act, 1937) and Codex/APEDA specifications for exports.
Treatments -
- Hot water treatment (HWT): mango 48 °C for 60 min (anthracnose, stem-end rot), while the USDA-accepted fruit-fly quarantine schedule is 46.1 °C for 65-90 min depending on fruit weight; vapour heat treatment (VHT) 47 °C core for 20 min and irradiation (150-700 Gy, used for Alphonso/Kesar to the USA at the Lasalgaon and Vashi facilities) are quarantine treatments against fruit fly.
- Fungicide/GRAS dips: carbendazim/thiabendazole historically, now increasingly restricted - check the current FSSAI/CIB&RC approved list and MRL before recommending any chemical.
- Calcium chloride (1-2%) or calcium nitrate dip - firms tissue, delays softening and ripening.
- Waxing - food-grade carnauba/shellac/mineral oil emulsion at 6-12% solids; reduces transpiration and improves gloss (citrus, apple, pomegranate, capsicum).
- Ethylene antagonists: 1-MCP (1-methylcyclopropene) blocks ethylene receptors - extends banana, apple, mango life; KMnO₄ ethylene scrubber sachets in packages; ethylene absorbers in CA stores.
- Curing - onion and garlic 3-5 days in shade/field until neck tightens; potato 10-15 days at 15-20 °C with 85-90% RH for wound periderm; sweet potato 29-32 °C.
- Degreening of citrus - 5-10 ppm ethylene at 22-25 °C for colour without ripening.
Packaging - see below.
Storage / transport / ripening / retail.

Packaging and transport

Functions: containment, protection from mechanical damage, modification of the internal atmosphere, convenience, information/branding, hygiene.
Types: CFB (corrugated fibre board) boxes - the standard unit pack, specified by bursting strength, ply (3/5/7) and ventilation area (4-6% of surface); plastic returnable crates (CHEP-type, 20-25 kg); wooden boxes (losing ground); gunny/mesh bags for onion and potato; punnets with cling/clamshells for grape, berry; leno/net bags; unitisation on pallets with stretch wrap; shrink wrap of individual fruit.
Cushioning: moulded paper/plastic trays, paper shreds, newspaper, foam nets (sleeves) for mango and pomegranate, grape guard (SO₂-generating sodium metabisulphite pads, ~4-7 g per 4 kg box) against *Botrytis*.
MAP (modified atmosphere packaging): the pack film's permeability plus produce respiration establish a steady state of low O₂ (2-5%) and raised CO₂ (3-8%). Passive MAP - sealing in a chosen film; active MAP - gas flushing. Films: LDPE, polypropylene, micro-perforated films. Risk: anaerobic respiration, off-flavour, if the film is too tight for the respiration rate.
Transport: head load/cycle → tractor trailer → truck → reefer (refrigerated) vehicle → rail (Kisan Rail) → air (perishable cargo at Nashik, Bengaluru, Delhi) → sea (reefer containers for banana, pomegranate, grape, mango to the EU/Middle East). Cold chain = unbroken temperature control from pre-cooling to retail; a single break in the chain shortens life irreversibly.

Storage systems

Cold storage (mechanical refrigeration): matched temperature, 85-95% RH, air circulation 20-60 air changes/h during cooling, and ventilation to remove ethylene/CO₂. India's cold storage capacity is roughly 37-39 million tonnes, but about 75% is single-commodity potato storage, concentrated in Uttar Pradesh, West Bengal, Punjab and Gujarat - the multi-commodity and pack-house gap is the standard exam/interview point.
Chilling injury: tropical and subtropical produce is damaged *above* freezing - banana below 13 °C (peel browning), mango below 10-12 °C (pitting, poor ripening), tomato below 7-10 °C, potato below 4 °C (sweetening from starch→sugar, so chip potatoes are stored at 10-12 °C with sprout suppressant), cucumber/brinjal 7-10 °C, litchi pericarp browning. Symptoms often appear only after transfer to ambient.
Freezing point: most produce freezes at −0.5 to −2 °C; apples and leafy are stored just above this.
CA (controlled atmosphere) storage: O₂ cut to 1-3% and CO₂ raised to 1-5% with active control (N₂ generators, CO₂ scrubbers), at optimum low temperature. Ultra-low-oxygen (ULO) and dynamic CA are refinements. In India CA is commercial for apple (Himachal Pradesh, Jammu & Kashmir - Adani Agrifresh Rewali/Bithal units) extending life from 4-5 months to 8-10 months.
MA storage - the same principle without active control (sealed room or liner).
Hypobaric (low-pressure) storage - laboratory/limited commercial.
Low-cost Indian structures: Zero Energy Cool Chamber (ZECC) - double brick wall with wet sand/riverbed sand and a wet jute cover, gives 10-15 °C below ambient and 90% RH, adds 3-8 days for vegetables; evaporative cool chamber, night ventilated onion storage (bottom and side ventilated, 25-30 °C, 65-70% RH - onion wants *low* humidity), potato heaps/clamps, on-farm shade and underground structures.
Ripening chambers: ethylene gas at 100 ppm (banana) / 100-150 ppm (mango) for 24-48 h at 18-22 °C and 90-95% RH, followed by ventilation to keep CO₂ below 1%. Calcium carbide is banned under the Food Safety and Standards (Prohibition and Restrictions on Sales) Regulations, 2011 - it yields acetylene with arsenic and phosphorus traces. Ethephon (ethrel) dip/sachet is permitted only as a controlled-release source outside the fruit in a ripening chamber; direct dipping of fruit in ethephon is not permitted - verify the current FSSAI direction, which has been updated more than once.
Minimal processing / fresh-cut: washing, peeling, cutting, 50-100 ppm chlorine or ozone wash, centrifugal drying, MAP, 0-5 °C; wound ethylene and browning (PPO) controlled with ascorbic/citric acid dips.

Regulation, schemes and standards in India

FSSAI under the Food Safety and Standards Act, 2006 - the Food Products Standards regulations cover fresh produce, the Contaminants/Toxins and Residues Regulations set MRLs (default 0.01 mg/kg for pesticides with no specified limit on a given crop), and the Food Safety and Standards (Packaging) Regulations, 2018 govern food-contact materials.
Agmark grading under the Agricultural Produce (Grading and Marking) Act, 1937; Legal Metrology Act, 2009 for net quantity declaration; Export (Quality Control and Inspection) Act, 1963 for export consignments.
APEDA - export promotion, and traceability systems: GrapeNet (mandatory for grape to the EU), AnarNet (pomegranate), MangoNet, HortiNet; registered pack-houses and treatment facilities; residue testing in NABL-accredited labs.
MIDH (Mission for Integrated Development of Horticulture) - subsidy for pack-houses, pre-cooling units, cold storage, reefer vans, ripening chambers; NHB and NHM components; AMI/AMIGS for marketing infrastructure; PMKSY (Pradhan Mantri Kisan Sampada Yojana) for integrated cold chain under MoFPI; Operation Greens for TOP (tomato-onion-potato) crops.
Quality systems an employer expects you to name: GlobalG.A.P. and IndG.A.P., HACCP, ISO 22000, FSSC 22000, and the IS standards on cold storage and on corrugated fibre board boxes (quote the current IS number only if certain - several older horticulture IS specifications have been revised or withdrawn).
Rates: fresh fruits and vegetables are nil/exempt under GST; processed, pre-packaged and branded products attract 5% or 18% (GST slabs since 22 September 2025 are 5%, 18% and 40%).

Key points

Climacteric - ripens after harvest with a respiration/ethylene peak (mango, banana, tomato); non-climacteric - does not (grape, citrus, litchi).
Temperature control - the single most effective tool; respiration (and so deterioration) roughly doubles per 10 °C rise (Q₁₀ = 2-4).
Pre-cooling - removal of field heat within hours of harvest; forced-air, hydro, vacuum, package icing, room cooling.
7/8 cooling time ≈ 3 × half-cooling time; cooling is an exponential approach to the medium temperature.
Chilling injury - damage above freezing in tropical produce: banana <13 °C, mango <10-12 °C, tomato <7 °C, potato <4 °C (sweetening).
Ethylene - the ripening hormone; 0.1-1 ppm is enough to trigger climacteric fruit; stored at 100 ppm in ripening chambers; blocked by 1-MCP, absorbed by KMnO₄.
Incompatibility - never store ethylene producers (banana, apple, mango) with ethylene-sensitive crops (leafy, cucumber, carrot, flowers); nor onion/garlic (needs 65-70% RH) with high-RH crops.
CA storage - 1-3% O₂, 1-5% CO₂ at low temperature; commercially used for apple in Himachal Pradesh and Jammu & Kashmir, roughly doubling storage life.
MAP - steady-state atmosphere created by the produce's own respiration inside a selected-permeability film; micro-perforated films for high respiration crops.
Curing - onion/garlic 3-5 days, potato 10-15 days at 15-20 °C for wound healing; separate from pre-cooling.
ZECC - zero energy cool chamber, double brick wall with wet sand, 10-15 °C below ambient, 90% RH; low-cost farm-level option.
Maturity indices - days from fruit set, TSS and TSS:acid, firmness, specific gravity, colour, starch-iodine, abscission.
Grape guard - sodium metabisulphite pad releasing SO₂ against *Botrytis*; waxing at 6-12% solids cuts transpiration.
Calcium carbide is banned for ripening in India; ripening must be by controlled ethylene gas in a chamber.
CIPHET loss estimates - roughly 4-15% by quantity for fruits and vegetables; India's cold storage capacity ~37-39 MT but about three-quarters is potato-only.
APEDA traceability nets - GrapeNet, AnarNet, MangoNet, HortiNet - and residue testing are mandatory for the EU/US trade.
MIDH/PMKSY - the subsidy routes for pack-houses, pre-cooling, cold storage, reefers and ripening chambers.

Formulas and examples

Respiration rate R = (CO₂ produced) / (mass × time), in mg CO₂ kg⁻¹ h⁻¹ (or mL CO₂ kg⁻¹ h⁻¹). Heat of respiration (W/t) ≈ 2.96 × R(mg CO₂ kg⁻¹ h⁻¹) approximately, since complete oxidation of glucose releases ~10.7 kJ per g CO₂, i.e. 1 mg CO₂ kg⁻¹ h⁻¹ ≈ 2.96 W per tonne.
Q₁₀ = R₂ / R₁ for a 10 °C rise; R at T₂ = R₁ × Q₁₀^{(T₂−T₁)/10}
Physiological loss in weight PLW (%) = (W₁ − W₂) / W₁ × 100, W₁ = initial mass, W₂ = mass after storage
Field heat to remove Q = m × cp × (Ti − Tf), with m in kg, cp in kJ kg⁻¹ K⁻¹ (most produce 3.6-4.0), temperatures in °C → Q in kJ
Specific heat (above freezing, Siebel) cp ≈ 0.837 + 0.0335 × W, W = water content in % (kJ kg⁻¹ K⁻¹)
Half-cooling time t½ from (T − Tm)/(Ti − Tm) = 0.5; cooling follows (T − Tm)/(Ti − Tm) = e^−kt; 7/8 cooling time t7/8 = 3 × t½
Refrigeration load = field heat load + respiration heat + transmission + air infiltration + equipment/personnel; 1 TR = 3.517 kW
TSS:acid ratio = TSS (°Brix) / titratable acidity (% as citric or malic acid)
Titratable acidity (%) = (mL NaOH × N of NaOH × meq. wt of acid × 100) / mL of sample; meq. wt = 0.064 for citric, 0.067 for malic
Shelf life extension factor ≈ ratio of respiration rates at the two temperatures (inverse)

Example 1 - respiration rate at a warmer temperature (Q₁₀). Tomato respires at 12 mg CO₂ kg⁻¹ h⁻¹ at 10 °C; Q₁₀ = 2.5. Rate at 30 °C?

Temperature rise = 20 °C → two Q₁₀ steps.
R = 12 × 2.5² = 12 × 6.25 = 75 mg CO₂ kg⁻¹ h⁻¹.
Deterioration is therefore about 6.25 times faster at 30 °C; a 15-day life at 10 °C falls to roughly 15/6.25 ≈ 2.4 days.

Example 2 - PLW and saleability. A 10 kg crate of okra weighs 9.42 kg after 3 days at ambient.

PLW = (10 − 9.42)/10 × 100 = 5.8% → above the ~5% wilting threshold for okra, so the lot is already downgraded.
Daily PLW = 5.8/3 ≈ 1.93% per day. At 10 °C with a perforated LDPE liner the same lot typically loses 0.3-0.5%/day, giving ~10-12 days before 5% - i.e. a 4-5 fold life extension from temperature plus liner.

Example 3 - field heat and refrigeration capacity for pre-cooling. Pre-cool 5 tonnes of mango from 32 °C to 13 °C in 6 hours; water content 83%, so cp ≈ 0.837 + 0.0335 × 83 = 0.837 + 2.7805 = 3.62 kJ kg⁻¹ K⁻¹ → close to mango's published measured value of about 3.74 kJ kg⁻¹ K⁻¹, which is used below.

Sensible heat Q = 5,000 × 3.74 × (32 − 13) = 5,000 × 3.74 × 19 = 355,300 kJ.
Cooling rate = 355,300 / (6 × 3,600 s) = 355,300/21,600 = 16.45 kW.
Respiration heat of mango at ~20 °C ≈ 60 W/t → 5 × 60 = 0.30 kW. Add roughly 25% for transmission, infiltration, fans and motors: total ≈ (16.45 + 0.30) × 1.25 ≈ 20.9 kW ≈ 5.9 TR. A 6 TR forced-air pre-cooler is specified.

Example 4 - forced-air cooling time. Grape enters a forced-air cooler at 28 °C; the room is at 1 °C; after 1 hour the berry centre reads 14.5 °C. Find k, the half-cooling time and the 7/8 cooling time.

(T − Tm)/(Ti − Tm) = (14.5 − 1)/(28 − 1) = 13.5/27 = 0.5 → half-cooling time t½ = 1.0 h, and k = ln2/1 = 0.693 h⁻¹.
7/8 cooling: ratio = 1/8 = 0.125 → t = ln(8)/0.693 = 2.079/0.693 = 3.0 h (= 3 × t½), reaching 1 + 0.125 × 27 = 4.4 °C.

Example 5 - TSS:acid ratio for a Kinnow consignment. 10 mL of Kinnow juice needs 6.4 mL of 0.1 N NaOH; refractometer reads 11.5 °Brix.

Acidity = (6.4 × 0.1 × 0.064 × 100)/10 = (6.4 × 0.1 × 6.4)/10 = 4.096/10 = 0.41% citric acid.
TSS:acid = 11.5/0.41 = 28:1 - well above the ~12:1 minimum, so the fruit is over-mature/low-acid: flat taste, short life. Harvest should have been earlier.

Crop	Storage temp (°C)	RH (%)	Approx. life	Note
Apple	0 to 1	90-95	4-6 months (8-10 in CA)	CA at 1-3% O₂
Mango (mature green)	10-13	85-90	2-4 weeks	Chilling below 10 °C
Banana (green)	13-14	90-95	2-4 weeks	Chilling below 13 °C
Grape	−0.5 to 0	90-95	2-3 months	SO₂ grape guard
Pomegranate	5-7	90-95	2-3 months	Husk scald risk
Citrus (Kinnow)	5-7	90-95	6-8 weeks	Degreen at 22-25 °C
Tomato (mature green)	10-13	90-95	2-3 weeks	<7 °C chilling
Potato (table)	2-4	90-95	6-8 months	10-12 °C for chips
Onion	25-30 or 0-2	65-70	4-6 months	Low RH, ventilated
Leafy vegetables	0-2	95-98	1-2 weeks	Vacuum/ice cooling

	Cold storage	CA storage	MAP	ZECC
Control	Temperature, RH	Temperature + O₂/CO₂, actively regulated	Gas composition inside the pack only	Evaporative cooling only
Capital cost	High	Very high	Low (film cost)	Very low (₹3,000-6,000 for ~100 kg)
Life gain	3-10×	1.5-2× over cold storage	1.5-2× over the same temperature	3-8 days
Typical Indian use	Potato, apple, grape, flowers	Apple in HP and J&K	Grape, fresh-cut, exports	Farm-level vegetables

Where it is used

Cold chain and logistics: Snowman Logistics, Coldman, Gubba, Adani Agrifresh, Container Corporation reefers - roles in pack-house operations, quality assurance and cold chain management.
Agri-export: grape (Nashik, Sangli to the EU under GrapeNet), pomegranate (Solapur), mango (Alphonso/Kesar by VHT/irradiation to the USA/Japan), banana (Jalgaon by sea reefer) - roles as APEDA-compliant pack-house QC and export documentation officers.
Organised retail and e-grocery: Reliance Fresh, DMart, BigBasket, Zepto, Ninjacart, Waycool - sourcing, grading standards, shelf-life management, shrinkage control.
Processing industry: Jain Irrigation (dehydrated onion, mango pulp), Hindustan Unilever, ITC, Varun Beverages, Mother Dairy Safal - raw-material intake grading, °Brix and acidity specifications.
Government and institutions: NHB and MIDH project appraisal, state horticulture departments, APMC/Terminal markets, FPO cold chain projects, CIPHET Ludhiana, ICAR-IIHR Bengaluru and the Division of Post Harvest Technology at IARI.
Infrastructure and equipment: suppliers of pre-coolers, ripening chambers, reefer vans and modified-atmosphere films; technical sales and commissioning roles.

Interview questions

Q: What is the difference between climacteric and non-climacteric fruits, and why does it matter commercially? A: Climacteric fruits show a post-harvest respiration and ethylene peak and ripen off the plant, so they can be shipped mature-green and ripened at destination; non-climacteric fruits must be harvested at eating ripeness, which limits their transport window.
Q: Why is pre-cooling called the most critical post-harvest operation? A: Field heat drives respiration, water loss and rot development; removing it within a few hours of harvest locks in quality, and no later refrigeration can recover life already lost.
Q: A mango consignment stored at 5 °C arrives firm and green but then ripens unevenly with pitted skin. Explain. A: Chilling injury - mango should not go below about 10-12 °C; symptoms typically appear only after transfer to ambient, as uneven ripening, surface pitting and poor flavour.
Q: Why can't bananas and leafy vegetables share a cold room? A: Bananas are strong ethylene producers and leafy vegetables are highly ethylene-sensitive (yellowing, leaf abscission); also their optimum temperatures differ by over 10 °C.
Q: What are the gas concentrations in CA storage of apple and how do they work? A: Oxygen is reduced to about 1-3% and CO₂ raised to about 1-5% at 0-1 °C; low O₂ slows respiration and ethylene action while raised CO₂ further inhibits ripening, roughly doubling storage life.
Q: Why is onion stored at 65-70% RH when most produce needs 90%? A: Onion bulbs are dormant and dry-scaled; high humidity causes root growth, sprouting and neck rot, so ventilated low-humidity storage at either 25-30 °C or 0-2 °C is used.
Q: Calcium carbide ripening - what is the legal and technical position? A: It is prohibited under the FSS (Prohibition and Restrictions on Sales) Regulations, 2011, because the acetylene it releases carries arsenic and phosphorus impurities; the legal method is controlled ethylene gas at about 100 ppm in a ripening chamber.
Q: How does MAP differ from CA storage? A: MAP lets the produce's own respiration and the film's permeability settle at a passive steady-state atmosphere inside a pack, with no active control; CA actively generates and regulates the gas composition in a whole room.
Q: What is PLW and what level is commercially critical? A: Physiological loss in weight from transpiration and respiration; roughly 5% (less for leafy, more for onion) causes visible shrivelling and makes the lot unsaleable.
Q: Why does potato for chips get stored at 10-12 °C and not 2-4 °C? A: Below about 4 °C starch converts to reducing sugars (cold-induced sweetening), which brown during frying; the warmer temperature needs a sprout suppressant and reconditioning instead.
Q: What is 1-MCP and where would you use it? A: 1-methylcyclopropene, a gaseous competitive blocker of ethylene receptors applied once post-harvest; used on apple, banana and mango to delay softening, with the caution that over-blocking can prevent normal ripening and flavour development.
Q: A grape exporter to the EU fails on residues. What does your process need to include? A: APEDA GrapeNet registration with plot-level traceability, a spray schedule limited to approved molecules with PHI respected, residue testing in a NABL-accredited lab against EU MRLs, and a registered pack-house with pre-cooling records.

Common mistakes

Treating all produce as needing the coldest possible store - ignoring chilling injury thresholds for banana, mango, tomato, potato and litchi.
Confusing curing (wound healing and drying, warm) with pre-cooling (heat removal, cold) - they are opposite in temperature and purpose.
Writing that CA storage is just a cold store with a plastic sheet - missing active O₂/CO₂ generation and scrubbing, and confusing it with MAP.
Quoting ethylene for ripening in percent instead of ppm (100 ppm = 0.01%), or forgetting to ventilate CO₂ out of the ripening chamber.
Mixing up maturity indices: giving TSS alone for citrus where the TSS:acid ratio is the standard, or specific gravity where days-from-fruit-set is the index.
Ignoring mechanical injury in answers - bruising during loose bulk transport is often the largest single avoidable loss, not storage temperature.
Using Q₁₀ arithmetically (adding) instead of as a power for each 10 °C step, or forgetting that cooling is exponential so the last fraction of heat takes the longest.