| Limes | [German version] |
Table of contents |
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| General: | ||
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Product information | |
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Packaging | |
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Transport | |
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Container transport | |
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Cargo securing | |
Product information
Product name
| German | Limetten |
| English | Limes |
| French | Limonettes |
| Spanish | Limas |
| Scientific | Citrus aurantiifolia |
| CN/HS number * | 0805 30 90 |
(* EU Combined Nomenclature/Harmonized System)
Product description
The lime, which belongs to the rue family (Rutaceae), comes originally from south-east Asia. Sour limes have a considerably greater share of the world market than sweet limes, with only sour limes being sold in Europe.
Like other citrus fruit, limes consist of three layers:
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the outer peel (flavedo layer), the glands of which exude the essential oils, which produce the typical citrus odor |
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the whitish albedo layer (inner layer of the peel) |
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the flesh of the fruit, consisting of approx. 8 – 10 segments, which contains the juice sacs. |
Limes are very similar to lemons in shape and appearance, but they generally have no apical nipple. The flavedo layer is initially dark green, but it changes in color through green to yellow as it ripens. If the lime is fully ripe, its peel becomes glossy. The greenish, generally seedless flesh is then very juicy and has a sour taste. Since the lime is more sensitive to cold than the other citrus fruits and its peel is thinner than that of the lemon, it is more problematic to transport.
Limes are subdivided into two groups of varieties:
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„West Indian, Mexican or Key lime“: small, containing seeds |
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„Tahiti lime or Persian lime“: larger, seedless, less aromatic |
According to [5], the change in the color of the peel is not a reliable measure of the ripeness of the fruit – it is peel gloss which indicates whether a fruit is ripe or not. Glossy limes are ripe, even if they are still green or have green spots. Another measure of ripeness is the Brix value, which determines the sugar/acid ratio of the juice.
Unlike many other citrus fruits, the peel of the lime is not chemically treated. The reason for this is that the peel is often used together with the pulp, and treated peel is toxic and flavor-impairing and therefore not suitable for eating.
Quality / Duration of storage
The fruit must not be overripe, as this limits its transport and storage life considerably. In addition, limes should not be completely yellow in color on dispatch.
Moldy fruit must be discarded, as contact with other fruit may result in cross-infection.
Various sources state maximum duration of storage as follows:
| Temperature | Relative humidity | Maximum duration of storage | Source |
|---|---|---|---|
| 11.5°C | 85 – 90% | 4 – 6 weeks | [1] |
| 10°C | 90% | 6 – 8 weeks | [3] |
| 8 – 12°C | 85 – 90% | 6 – 8 weeks | [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 |
|---|---|---|---|---|
| 11.1 – 12.8°C | 85 – 90% | 5% | 0 – 10% | good |
Intended use
Limes are used to garnish cold drinks and season food. They are also frequently used to produce juice concentrates.
Figure
(Click on the Figure to enlarge it.)
 Figure 1 |
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 | |
| Africa | Kenya, Egypt, South Africa |
| Asia | Malaysia, India, Sri Lanka, Israel |
| America | USA (Florida, California), Mexico, Dominican Republic, Caribbean, Brazil, Ecuador |
| Australia |
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Packaging
Limes are transported in crates, fruit crates and cartons.
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Transport
Symbols
 General cargo |
 Temperature-controlled |
Means of transport
Ship, aircraft, railroad
Container transport
Refrigerated container with fresh air supply or controlled atmosphere.
Cargo handling
Since limes are highly sensitive to impact due to their relatively thin skins, they must 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
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1.30 – 1.64 m3/t (cartons) [1] |
The stowage factor depends very much on weight categories and the packaging units used.
Stowage space requirements
cool, dry, well ventilated
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
Limes 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 | 11.5°C | [1] |
| 10°C | [3] | |
| 8 – 12°C | [5] | |
| Supply air | 11°C | [1] |
Depending on the variety, the chilling damage temperature for limes is 5 – 12°C.
To ensure maximum transport and storage life, the fruit should be cooled immediately postharvest, as limes, like other citrus fruit, are susceptible to mold.
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RF Humidity/Moisture
Limes require particular temperature, humidity/moisture and ventilation conditions (SC VII) (storage climate conditions).
| Designation | Humidity/water content | Source |
| Relative humidity | 85 – 90% | [1] |
| 90% | [3] | |
| 85 – 90% | [5] | |
| Water content | 83 – 89% | [1] |
| Maximum equilibrium moisture content | 80% | [1] |
Limes must be protected from all forms of moisture (seawater, rain and condensation water), to prevent premature spoilage (mold damage).
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RF Ventilation
Limes 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.
The circulation fans must where possible be set to full power for the entire duration of transport. After the reduction period, it is essential to supply fresh air to keep the CO2 content below 0.2 vol.%.
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RF Biotic activity
Limes 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 | CO2 evolution at 11°C: 13 mg/kg*h |
| Upper limit of permissible CO2 content | 0.2 vol.% |
| Ethylene evolution | |
| Active behavior | The rate of ethylene production is very low, being below 0.1 µl/kg*h [16]. |
| Passive behavior | Limes are moderately sensitive to ethylene [16] (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. The TLV for CO2 concentration is 0.49 vol.%.
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RF Self-heating / Spontaneous combustion
No risk.
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RF Odor
| Active behavior | Limes have a strong, pleasant odor. |
| Passive behavior | The cargo is highly odor-sensitive and must therefore not be stored together with odor-emitting products. |
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RF Contamination
| Active behavior | Limes do not cause contamination. |
| Passive behavior | The cargo is sensitive to 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
Because of its high impact- and pressure-sensitivity, the fruit must be treated with great care during cargo handling, transport and storage, since otherwise it will spoil prematurely.
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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
The normal weight loss due to a reduction in the moisture content of the product is approx. 1 – 2% [1].
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RF Insect infestation / Diseases
Blue mold rot or storage rot is the most feared storage disease of citrus fruits and is caused by two species of mold: green mold (Penicillium digitatum), which is of an olive-green color, and blue mold (Penicillium italicum), which is of a blue-green color. The fungal spores mainly penetrate through small injuries. Development is optimal at 20 – 27°C; growth still flourishes at 10°C and comes to a standstill only at 4°C. Blue mold is transferred from fruit to fruit by contact.
Seawater, rain and condensation water promote green and blue mold growth.
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.
Chilling damage is manifested in citrus fruits in particular by spots on the peel (brown dots on the peel), accompanied by a bitter taste and unpleasant odor, rot and cell wall collapse. The glossiness of the peel is lost and the albedo layer (inner layer of the peel), which is normally white, turns a dark color. When the fruit is divided up, the segments, which have a low juice content, break up and the whole fruit is glassy and soft. The severity of the chilling damage is determined not only by the extent to which the temperature has fallen beneath the limit, but also by the length of exposure to this temperature.
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