Chestnuts [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 Maronen (Esskastanien), Edelkastanien
English Chestnuts, sweet chestnuts
French Marrons
Spanish Castañas
Scientific Castanea sativa
CN/HS number * 0802 40 00


(* EU Combined Nomenclature/Harmonized System)



Product description

Sweet chestnuts are edible nuts which grow on trees of the genus Castanea in the beech family (Fagaceae). Chestnuts are native to the Black Sea area.

They have an spiky, external husk (cupule) which spontaneously breaks open when ripe to reveal the actual fruit. The outer husk may contain 1 - 3 fruits. The fruit consists of the light colored nut kernel, a thin skin and a red-brown to brown pericarp. The base of the nut has a light colored spot, also known as the "navel".

Chestnuts are of a round to oval shape. Their flavor may be described as nutty. Boiling or roasting imparts a still stronger aroma to chestnuts. Cooking also makes it easy to remove the skin and shell from the nut kernel.

The nut kernel predominantly consists of starch, protein, minerals and chestnut oil. For a nut, its vitamin C content is relatively high.

The oil content of chestnuts is 1 - 2% (chestnut oil).

There is a very large number of different varieties of chestnuts, just one of which is the "keeping" chestnut, which remains on the tree longer than normal chestnuts and must be picked by hand.


Quality / Duration of storage

Chestnuts exhibiting mold growth on acceptance of a consignment must be rejected. If, on unloading, they exhibit mold growth, they should not be placed in full sunshine as this does not delay decomposition, but instead encourages it. Once mold growth has started, it cannot be stopped.

The fruits must not exhibit any mechanical damage either.

Various sources state maximum duration of storage as follows:

Temperature Rel. humidity Max. duration of storage Source
0°C not stated 6 months [5]
-3 - 0°C 65 - 75% 12 months [18]


Due to their poor keeping qualities (high water content), chestnuts are sold not as nuts, but instead as fresh fruit, unless they have been sun-dried.


Intended use

Boiled chestnuts are served as an accompaniment to various meat dishes or are pureed.

Roast chestnuts sold as a snack during the cold winter months.

Before boiling or roasting, chestnuts are provided with a crosswise nick at the tip and either boiled for five minutes and then shelled or are roasted, after which the shells easily burst open.


Figures

(Click on the individual Figures to enlarge them.)

Photo, chestnuts

Figure 1
Drawing, chestnuts

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, France, Italy, Spain, Portugal, Romania, Greece, Turkey
Africa  
Asia Japan, Korea, China
America USA
Australia  


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Packaging

Chestnuts are mainly transported in bags, boxes or drums.


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Transport

Symbols

Symbol, general cargo

General cargo


Temperature-controlled



Means of transport

Ship, truck, railroad


Container transport

Refrigerated container with fresh air supply


Cargo handling

Since chestnuts are sensitive to impact, they must be handled with appropriate care.

In damp weather (rain, snow), the cargo must be protected from moisture, since it may lead to mold growth.

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


Stowage factor

3.34 - 3.48 m3/t (in boxes) [11]
5.02 - 5.57 m3/t (in bags) [11]
3.96 m3/t (in bags) [1]


Stowage space requirements

Cool, dry, well ventilated


Segregation

Fiber rope, thin fiber nets


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).

Care must be taken during stowing to ensure that the cargo is not only well secured but is also very well ventilated.


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Risk factors and loss prevention

RF Temperature

Chestnuts 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
Favorable travel temperature range 1 - 3°C [1]
0°C [5]
-3 - 0°C [18]


Excessive heat during storage causes chestnuts to germinate.


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RF Humidity/Moisture

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

Designation Humidity/water content Source
Relative humidity 70% [1]
65 - 75% [18]
Water content 25 - 30% [1]
Maximum equilibrium moisture content 85% [1]


According to [15], the water content of chestnuts may be as high as 50.1%, as a result of which they are constantly releasing water vapor. Fresh chestnuts release particularly large quantities of water vapor due to vigorous respiration, so causing self-heating and mold growth.

Chestnuts must be protected from all forms of moisture (seawater, rain and condensation water) to prevent mold, rotting, fermentation and sprouting.


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RF Ventilation

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

Recommended ventilation conditions: circulating air, 10 - 20 circulations/hour with continuous supply of fresh air (airing).

In order to reduce the risk of germination and sprouting, water vapor and CO2 must be removed continuously and an adequate supply of fresh air must be ensured. Packaging must be constructed so as to ensure adequate ventilation. Where possible, the cargo should be stowed so as to leave trenches.


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RF Biotic activity

Chestnuts display 2nd order biotic activity.

Chestnuts 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 Chestnuts (especially when fresh) constantly release CO2 .
Upper limit of permissible CO2 content 0.8 vol.%


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

Chestnuts have a tendency towards self-heating under the influence of moisture.


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RF Odor

Active behavior Chestnuts release a slight, unpleasant odor.
Passive behavior Chestnuts are sensitive to unpleasant or pungent odors.



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RF Contamination

Active behavior Chestnuts 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 their high mechanical sensitivity, chestnuts must be treated with great care during cargo handling, transport and storage, since otherwise they may suffer a reduction in quality.


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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

Loss of weight must be expected due to the release of water vapor, especially from fresh chestnuts.


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RF Insect infestation / Diseases

Chestnut blight: Chestnut blight (Endothia parasitica) attacks and destroys the bark and wood of the chestnut tree.

Ink disease: Infection with ink disease (Phytophthora cinnamoni), which attacks the roots of the tree, is manifested externally by leaf yellowing and die-back of branches.

Maggot infestation: Chestnuts are sometimes infested with maggots, one common culprit being the insect Carpocapsa splendam.

Mold growth: Once mold growth has started, it cannot be stopped and the damage is thus irreversible.

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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