Tea [German version]

Table of contents

Product information
  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
    Additional information

Product information

Product name

German Tee
English Tea
French Thé
Scientific Camellia sinensis
CN/HS number * 0902 ff.

(* EU Combined Nomenclature/Harmonized System)

Product description

Tea consists of the fermented and dried leaves, leaf buds and tender stems of the evergreen tea bush of the Theaceae family. Tea is a high quality semiluxury item, the stimulant action of which results from its content of 2.5 - 5% of thein. At certain intervals, the tea bushes are cut back to a height of 1 m. Tea is always harvested as two leaves and one bud. Tea is cultivated in plantations (tea gardens).

The principal tea cultivating countries are in the tropics and subtropics. Unlike green coffee beans and raw cocoa, tea is exported in ready-to-use form. It is a cargo which demands the utmost care. Shipping period starts approx. 6 weeks after harvest, with the tea shipped at the beginning of a season being the most valuable. Later varieties of tea are mostly of lower quality. The crop is harvested all year round, with the following exceptions:

Country of origin Designation Time of harvest
Sri Lanka Dimbula March
Uva July, August
India First flush March, April
Second flush July, August

The following types are differentiated on the basis of processing:

Green tea
Black tea (orthodox or CTC production)

Green tea: With green tea, the freshly picked leaves are steamed, rolled and dried so that the green color of the chlorophyll is retained. The fermentation process is omitted.

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Figure 1: Processing flowchart for green tea

Black tea: 

Orthodox production

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Figure 2: Processing flowchart for black tea
(processing in country of production),
"orthodox" production

CTC production

CTC differs from orthodox production solely in that, after rolling and before fermentation, the tea is uniformly shredded with a CTC machine, so shortening the overall production time by approx. 50%. This method yields powerfully flavored, quick brewing teas which, while they are not of very high quality, are particularly suitable for producing tea bags.

Quality / Duration of storage

A distinction is drawn between the China tea plant (e.g. from China, Japan and Taiwan) and the Assam tea plant (e.g.. from India, Sri Lanka, Indonesia and Vietnam), each variety yielding both leafy and broken grades of tea. Teas are also classified and graded depending upon the size of the tea leaves. The youngest, small top leaves (= pekoe tips) provide the most valuable teas, while the older, large bottom leaves provide less valuable grades.

Grades of tea are classified by

country of origin
leaf size/shape

,e.g. Darjeeling (district in Northern India), F.O.P. (flowery orange pekoe).

The following table provides an overview of the various grades [4]:

Leafy/Broken Abbreviation Designation Leaf shape
Leafy grades F.O.P. Flowery Orange Pekoe Thin, wiry, often with a light covering of silky hairs
O.P. Orange Pekoe Slightly twisted, often with white to golden yellow tips
P. Pekoe Somewhat coarser
S. Souchong Coarse
K. Kongo Very coarse
Broken grades F.B.O.P. Flowery Broken Orange Pekoe  
B.O.P. Broken Orange Pekoe  
B.P. Broken Pekoe  
B.T. Broken Tea  
Lower grades F. Fannings The leaf particles and fragments obtained during processing
D. Dust Finely divided tea dust
B. Bohea  

The product may be shipped as soon as 3 - 4 weeks after harvest, but 1.5 - 2.5 months may elapse before shipping. The tea shipped at the beginning of the season is the most valuable. Shipping tea later after harvest than this may result in quality degradation during transport, which may particularly affect the light southern Indian tea.

Otherwise, tea has a long storage life of 18 months or more provided that proper transport and storage conditions are maintained. However, this does not apply to aromatized teas.

Intended use

Tea leaves are used to make an infused beverage which is classed as a semiluxury item.


(Click on the individual Figures to enlarge them.)

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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 Georgia, Turkey
Africa East Africa
Asia India, Sri Lanka, Indonesia, Bangladesh, China, Japan, Nepal, Taiwan, Turkey, Vietnam, Pakistan
America Argentina, Brazil

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Tea is packaged in light plywood chests which are lined with aluminum foil and one or two plies of parchment paper, so providing aroma-proof packaging. The corners are covered with sheet metal to reinforce the chests and protect the contents from humidity/moisture and foreign odors. Plywood chests from China and India are often additionally protected by bast mats or fabric.

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Figure 16
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Classification by net weight:

Whole chest 35 - 60 kg [2] or 40 - 73 kg [1]
½ chest 20 - 40 kg [2] or 30 - 40 kg [1]
¼ chest/box 9 kg [1]
Paper and jute bags 25 - 60 kg [2]

China tea is also shipped in tinplate containers which are sealed with solder and additionally wrapped with bast mats.

Sample chests are marked with a cross and a special stamp to indicate this status. Sample chests must be stowed separately and accessibly. Tea chests which have been additionally packaged and sealed in the country of origin are described as "country coopered packages", while those which are so packaged only on arrival at the port of destination are described as "dock coopered packages" [50].

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Symbol, general cargo

General cargo

Means of transport

Ship, truck, railroad, aircraft (transport of sample chests to port of destination for purposes of comparison). Tea, especially Darjeeling, is increasingly being transported by air and is known as "air freighted" tea.

Container transport

Tea is predominantly transported in standard containers. Containers intended for loading have to be watertight and must not be contaminated in any way. Containers whose floors release a foreign odor, are contaminated by any substances or are too damp should be rejected. Below deck stowage is required, to rule out the possibility of exposure to rain or seawater or of overheating by day and cooling at night. Tea in containers should be stowed away from sources of heat.

Carton dimensions are adapted to container dimensions and allow the containers to be filled virtually to total capacity. These two features mean that the standard container can be used without difficulty as FCL cargo.

Cargo handling

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

Hooks must not be used because they can tear or puncture the chests, resulting in loss of the contents. Do not use slings or cargo nets. Handling on pallets has proved most effective because this reduces the risk of breakage since the chests can be stacked in a uniform block.

Stowage factor

2.60 m3/t (framed plywood chest, 50 kg) [1]
2.79 - 3.07 m3/t (paper bags) [11]

Stowage space requirements

Cool, dry, good ventilation


Synthetic fiber rope, thin fiber nets

Cargo securing

Because of the impact- and pressure-sensitivity of the cargo, it must be secured in such a way that damage is prevented. Spaces between packages or pallets must be filled, to prevent slippage or tipping. Pallets must be loaded flush with their edges as protruding packages may readily result in damage.

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Risk factors and loss prevention

RF Temperature

Tea requires particular temperature, humidity/moisture and possibly ventilation conditions (SC VI) (storage climate conditions).

Favorable travel temperature range: 5 - 25°C [1] [2] [4]

Tea must be stowed away from sources of heat in order to avoid the risk of desiccation and drying.

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RF Humidity/Moisture

Tea requires particular temperature, humidity/moisture and possibly ventilation conditions (SC VI) (storage climate conditions).

Designation Humidity/water content Source
Relative humidity 60% [1]
50 - 60% [2]
50 - 60% [4]
Water content 4 - 6% (black tea) [1]
4 - 6% (black tea) [4]
Maximum equilibrium moisture content 65% [1]

The sorption isotherms for black tea of the Darjeeling and Lapsang Souchong varieties rise steeply, reflecting the tea's strong hygroscopicity. The water contents of 4 - 6% are at equilibrium with very low relative humidities. Tea dust, in contrast, exhibits only slightly hygroscopic behavior. Water contents of 2 - 4% are recommended for tea dust.

Sorption isotherm, tea

Figure 19
Sorption isotherm, tea

Figure 20
Sorption isotherm, tea

Figure 21

Tea is extremely sensitive to moisture/humidity. Moisture, for example due to rain, seawater or condensation water, results in mold growth and mustiness. Moldy or musty tea is unusable, its musty flavor making it worthless.

Tea chests require dry holds with good ventilation facilities and must not exhibit any damage due to sweat. Dripping sweat causes severe soiling of the tea chests, the contents of which must then be repackaged. Dunnage must accordingly be carefully laid in the hold and the ship's sides covered with mats, so that the tea chests cannot come into contact with steel parts. Mats or packaging paper must be laid over the chests at potential drip points.

Moisture damage may even originate during processing. Tea chests which have come into contact with water become speckled or the uppermost layer of chests becomes uneven.

If moisture damage is suspected, testing is performed using the silver nitrate method, to find out whether chloride solutions (seawater) or fresh water (condensation or rain) are the cause.

The water content of black tea must not fall below 2%, as the product otherwise becomes hay-like and its essential oils readily volatilize, while on the other hand, it must not exceed 9% [2] as it then has a tendency to grow mold and become musty.

The wood of the chest should have a water content of 10 to at most 12%, corresponding to an equilibrium moisture content of 60 - 70%. The same applies to any wooden flooring/ceiling in containers/holds.

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RF Ventilation

Tea requires particular temperature, humidity/moisture and possibly ventilation conditions (SC VI) (storage climate conditions).

If the product is at "shipping dryness", i.e. if there is no risk of degradation by mold etc. due to water content, ventilation is not required. If this is not the case, the following ventilation measures should be implemented:

Recommended ventilation conditions: air exchange rate: 10 changes/hour (airing)

Protect from odor tainting by ventilation equipment (see RF Odor).

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RF Biotic activity

Tea displays 3rd order biotic activity.

It belongs to the class of goods in which respiration processes are suspended, but in which biochemical, microbial and other decomposition processes still proceed, which, especially as a result of postfermentation, are associated with consumption of O2 and evolution of CO2.

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RF Gases

No risk.

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RF Self-heating / Spontaneous combustion

Oil content: 1% essential oils

No risk.

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RF Odor

Active behavior Tea has a strong, pleasant odor.
Passive behavior Tea is extremely odor-sensitive and must not be stowed together with odoriferous products. Tea immediately absorbs any foreign odor.

For this reason, many freight contracts contain a special tea clause stipulating that certain goods which could impair the aroma of tea must not be stowed in the same compartment. Such products in particular include sugar, safflower (thistle-like plant from the East Indies used in dyeing), rhubarb, rubber, rapeseed, hides, turmeric (curcuma rhizome of an Indian spice plant), cassia or drugs.

Due to possible odor contamination, tea must not be stowed together with, among others, copra, tar, tarred wire, ginger, silk waste, camphor, oil cake, tobacco, fruit, essential oils, pepper, baled feathers and strong-smelling chemicals.

Tea experts are able to establish whether the chests have been stowed together with such products. Impairment of odor also has an impact on flavor, making the tea undrinkable. Odor-tainted tea may, under certain circumstances, still be salable for subsequent blending with cheap grades and for industrial purposes.

If used chests, the lumber of which has suffered fungal attack, are used, there is a risk that the tea will absorb the moldy odor.

Odor tainting may also be caused by the use of pesticides in the growing regions or in intermediate warehousing.

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RF Contamination

Active behavior Tea does not cause contamination.
Passive behavior Tea is extremely sensitive to contamination and must thus be kept absolutely clean and should not be stowed together with dusty or oily cargoes (e.g. peanuts, palm kernels or the like).

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RF Mechanical influences

Tea chests are extremely sensitive to mechanical stresses. The very thin plywood sheets from which they are made break, burst and tear under even very slight stresses and such breakage then generally damages the internal aluminum foil and parchment paper resulting in losses of aroma and reduced tea quality.

Use of hooks must be prohibited because they can tear or puncture the chests, resulting in loss of the contents. In order to avoid causing damage, chests should also never be transferred with slings or cargo nets, but should instead be handled on pallets.

Mechanical damage is often caused by exceeding stack heights. When in intermediate storage, 50 kg chests may be stowed 5 high. However, on board an ocean-going vessel or in containers, they should only be stowed 4 high (stack height approx. 2 m) as they are subjected not only to static loads, but also to dynamic stresses (mechanical stresses) due to the motion of the ship/handling operations. Total loss generally occurs at stack heights of 7 - 8 units. According to [11], palletized chests should be stacked no more than 3 high. Pallets holding chests must not be overstowed with other pallets.

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RF Toxicity / Hazards to health

No risk.

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RF Shrinkage/Shortage

Frequent handling or severe mechanical stresses (e.g. due to excessive stack heights) may result in breakage of the chests and thus loss of volume.

Since tea is a valuable cargo, the risk of theft is not negligible. Chests should be inspected for signs of force having been applied (damage to plywood or to metal strips). For example, nails which have been extracted so as to remove the content of the chest can be identified because they are a little loose or stick out. If the chests are refilled with other materials to replace the weight of the removed contents, it is difficult to detect possible theft by check-weighing.

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RF Insect infestation / Diseases

Chests of tea are at particular risk of infestation by pests (e.g. tobacco beetles, copra beetles, drugstore beetles or cockroaches) during storage at the port before shipping. Storage conditions should thus be investigated at the port of loading. If beetle infestation is suspected, one or two tea chests should be selected from each batch in the warehouse. These chests should then be wrapped in two or three layers of oiled paper, with the seams being sealed with adhesive tape. Once wrapped, these chests should be stowed separately from the remainder of the tea cargo. If beetle infestation is then observed in the main batch at the port of discharge, the sample chests may provide an indication as to whether infestation occurred before loading (samples also infested) or after loading (samples not infested). If no assessors are available, this measure may serve as a stopgap. The cargo must also be inspected for attack by rats and mice.

Tea is traded with a certificate of origin.

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Additional information

Claims for damages must be thoroughly investigated and an answer provided to the following questions [2]:

What route did the consignment follow and in which season?
Where is the odor impaired in the chests: only at the edges or in the middle?
How were the chests transported:
  conventional loading
  container shipment
  type of container
  position of the container on the ship
Have tea tasters been involved in the claim for damages?
Were analyses carried out by a food chemist?

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