Cucumbers [German version]

Table of contents

General:
Product information
Packaging
Transport
  Container transport
  Cargo securing


Risk factors and loss prevention:
Temperature Odor
Humidity/Moisture Contamination
Ventilation Mechanical influences
Biotic activity Toxicity / Hazards to health
Gases Shrinkage/Shortage
Self-heating / Spontaneous combustion Insect infestation / Diseases




Product information

Product name

German Gurken
English Cucumbers
French Concombres
Spanish Pepinos
Scientific Cucumis sativus
CN/HS number * 0707 00 ff.


(* EU Combined Nomenclature/Harmonized System)



Product description

Cucumbers, botanically berry fruit, belong to the gourd family (Cucurbitaceae) and have juicy, fibrous flesh. Due to its subtropical origins, the cucumber's heat requirements are high and it is therefore cultivated predominantly as a greenhouse product.

There are two principal varieties, distinguished by their manner of cultivation:

slicing cucumbers, snake cucumbers: these are cultivated in greenhouses and polytunnels and are therefore largely unaffected by external weather conditions, making them suitable for cultivation virtually anywhere in the world. They are approx. 40 cm long, reach a diameter of 10 cm and are smooth-skinned.
pickling cucumbers: these are outdoor-grown and therefore have particular climatic requirements. They are sometimes only a few cm long, but may grow as long as 20 cm, and are thick and rough-skinned.


When unripe, cucumbers are green-colored. As they ripen, they turn yellowish-white or yellowish-brown. Modern cucumbers are basically free from bitter substances. However, the bitter substance elaterin may sometimes form in pickling cucumbers in particular, where it may be present in particularly large quantities at the stem-end.


Quality / Duration of storage

Cucumbers should be green, smooth and as seedless as possible.

Yellowness of the skin indicates overripeness. Cucumbers in this condition are no longer suitable for transport. Cucumbers should also be clean and undamaged, to prevent quality degradation during transport. Cucumbers which exhibit signs of gray mold rot, cucumber scab or chilling damage must be rejected prior to loading.

Maximum duration of storage is as follows:

Temperature Rel. humidity Max. duration of storage Source
10 - 12°C 85 - 90% 14 days [1]
7 - 10°C 90 - 95% 10 - 14 days [5]


Where controlled atmosphere transport is used, transport and storage duration may be extended. The following parameters apply in such a case [16]:

Temperature Rel. humidity O2 CO2 Suitability for controlled atmosphere
10 - 11.1°C 90 - 95% 3 - 5% 5 - 7% Moderate



Intended use

Cucumbers may be used with or without their skins. They are eaten raw in salads, but may also be cooked as a vegetable.

Industrial processing of cucumbers mainly takes the form of pickling, either whole or peeled and sliced.


Figure

(Click on the individual Figures to enlarge them.)

Photo, cucumbers

Figure 1
Drawing, cucumbers

Figure 2



Countries of origin

This Table shows only a selection of the most important countries of origin and should not be thought of as exhaustive.

Europe Germany, Holland, Greece, Spain, Canary Islands, France, Italy, Belgium, Turkey, Romania, Hungary, Bulgaria, Poland, former Yugoslavia, Russia
Africa  
Asia China, Japan
America USA, Argentina
Australia  


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Packaging

Cucumbers are packaged in various ways, including in strong cartons of corrugated board with plastic film lining. The sides of the cartons are reinforced and provided with perforations. The individual cucumbers are often heat-sealed in gas-permeable plastic film, which extends storage life.


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Transport

Symbols

Symbol, general cargo

General cargo
Symbol, temperature-controlled

Temperature-controlled



Means of transport

Ship, truck, railroad, aircraft


Container transport

Refrigerated container with fresh air supply or controlled atmosphere.


Cargo handling

Because of their impact- and pressure-sensitivity, cucumbers have to be handled with appropriate care.

The required refrigeration temperature must always be maintained, even during cargo handling.

In damp weather (rain, snow), the cargo must be protected from moisture, as there is otherwise a risk of premature spoilage.


Stowage factor

2.00 m3/t (corrugated board cartons) [1]


Stowage space requirements

Cool, dry, good ventilation


Segregation

Fiber rope, thin fiber nets, wooden dunnage


Cargo securing

Because of its considerable impact- and pressure-sensitivity, packages of this cargo must be secured in such a way that they are prevented from damaging each other. Spaces between packages or pallets must be filled, to prevent slippage or tipping. By selecting the correct packaging size or cargo unit (area module or area module multiple), holds can be tightly loaded (without spaces).


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Risk factors and loss prevention

RF Temperature

Cucumbers require particular temperature, humidity/moisture and ventilation conditions (SC VII) (storage climate conditions).

A written cooling order must be obtained from the consignor before loading is begun. This order must always be complied with during the entire transport chain.

The following Table merely constitutes an estimate of appropriate temperature ranges. Temperatures may deviate from these values, depending on the particular transport conditions.

Designation Temperature range Source
Travel temperature 10 - 12°C [1]
7 - 10°C [5]
13°C [20]


The cargo and holds/containers should be precooled prior to loading.

Cucumbers are very susceptible to physiological chilling damage, which occurs at temperatures < 7°C. Chilling damage manifests itself initially in soft, water-soaked, easily depressed spots on the skin; this is later followed by the discharge of liquid and detachment of the epidermal layers. Affected cucumbers rapidly become glassy and tasteless. A bacterial and/or fungal secondary infection may occur at the injured points. The supply air temperature must not fall below 7°C.

Travel temperatures higher than approx. 12°C reduce the storage life of the cargo, causing the cucumbers to turn yellow, so making them unsalable.


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RF Humidity/Moisture

Cucumbers require particular temperature, humidity/moisture and ventilation conditions (SC VII) (storage climate conditions).

Designation Humidity/water content Source
Relative humidity 85 - 90% [1]
90 - 95% [5]
90 - 95% [20]
Water content 95 - 97% [1]
Maximum equilibrium moisture content 85% [1]


Cucumbers must be protected from all forms of moisture (seawater, rain and condensation water), since there is otherwise an increased risk of wet or white rot.


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RF Ventilation

Cucumbers require particular temperature, humidity/moisture and ventilation conditions (SC VII) (storage climate conditions).

Recommended ventilation conditions: circulating air, 60 - 80 circulations/hour with continuous supply of fresh air, to prevent excessive concentrations of CO2, ethylene and other gases.


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RF Biotic activity

Cucumbers display 2nd order biotic activity.

They are living organs in which respiration processes predominate, because their supply of new nutrients has been cut off by separation from the parent plant.

Care of the cargo during the voyage must be aimed at controlling respiration processes (release of CO2, water vapor, ethylene and heat) in such a way that the cargo is at the desired stage of ripeness on reaching its destination. Inadequate ventilation may result in fermentation and rotting of the cargo as a result of increased CO2 levels and inadequate supply of atmospheric oxygen (see Ventilation).


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RF Gases

CO2 evolution In cucumbers, metabolic processes continue even after harvesting. Cucumbers absorb oxygen and release carbon dioxide, ethylene and heat.
Upper limit of permissible CO2 content 0.2 vol.%
Ethylene evolution  
Active behavior Cucumbers produce small quantities of ethylene, their ethylene production rate being 0.1 - 1.0 µl/kg*h [16].
Passive behavior The sensitivity of cucumbers to ethylene may be classified as high [16]. They must not therefore be stored together with ethylene-producing goods (allelopathy).


If ventilation has been inadequate (frost) or has failed owing to a defect, life-threatening CO2 concentrations or O2 shortages may arise. Therefore, before anybody enters the hold, it must be ventilated and a gas measurement carried out.


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RF Self-heating / Spontaneous combustion

No risk.


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RF Odor

Active behavior Cucumbers have a very slight, pleasant odor.
Passive behavior Cucumbers are highly sensitive to the odors of other products and must therefore not be stored together with odor-emitting products.



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RF Contamination

Active behavior Cucumbers do not cause contamination.
Passive behavior Cucumbers are sensitive to contamination by dirt, fats and oils. The holds or containers must accordingly be clean and in a thoroughly hygienic condition before loading.



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RF Mechanical influences

Cucumbers are highly impact- and pressure-sensitive. They should not be thrown, since the resultant bruises rapidly result in spoilage of the cucumbers.

Walking over the cartons likewise always causes damage and should therefore be avoided. Packaging should be such that homogeneous stuffing up to a height of 2.40 m may be achieved.


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RF Toxicity / Hazards to health

If ventilation has been inadequate (frost) or has failed owing to a defect, life-threatening CO2 concentrations or O2 shortages may arise. Therefore, before anybody enters the hold, it must be ventilated and a gas measurement carried out. The TLV for CO2 concentration is 0.49 vol.%.


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RF Shrinkage/Shortage

Drying-out of the cargo may cause weight losses of < 1%.


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RF Insect infestation / Diseases

The most important diseases are:

gray mold rot (Botrytis cinerea): glassy, watery, then layers of mouse-gray mold.

Drawing, cucumbers

Figure 3

Cucumber scab (Cladosporium cucumerinum): deeply sunken spots covered with layers of green spores and oozing milky-white or brown droplets.


The quarantine regulations of the country of destination must be complied with and a phytosanitary certificate may have to be enclosed with the shipping documents. Information may be obtained from the phytosanitary authorities of the countries concerned.


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