Nuts and Kernels
|Infobox on Nuts and Kernels|
|Example of Nuts and Kernels|
|Stowage factor (in m3/t)|
|Humidity / moisture||Hazelnuts|
|Ventilation||Air exchange rate: at least 10 changes/hour (airing)|
|Risk factors||See text|
Nuts and Kernels
A nut is a fruit composed of a hard shell and a seed, where the hard-shelled fruit does not open to release the seed (indehiscent). So, while, in a culinary context, a wide variety of dried seeds are often called nuts, in a botanical context, only ones that include the indehiscent fruit are considered true nuts. The translation of "nut" in certain languages frequently requires paraphrases as the concept is ambiguous.
Most seeds come from fruits that naturally free themselves from the shell, unlike nuts such as hazelnuts, chestnuts, and acorns, which have hard shell walls and originate from a compound ovary. Culinary usage of the term is less restrictive, and some nuts as defined in food preparation, like pistachios and Brazil Nuts, are not nuts in a botanical sense. Common usage of the term often refers to any hard-walled, edible kernel as a nut.
Nuts are an important source of nutrients for both humans and wildlife. Because nuts generally have a high oil content, they are a highly prized food and energy source. A large number of seeds are edible by humans and used in cooking, eaten raw, sprouted, or roasted as a snack food, or pressed for oil that is used in cookery and cosmetics. Nuts (or seeds generally) are also a significant source of nutrition for wildlife. This is particularly true in temperate climates where animals such as jays and squirrels store acorns and other nuts during the autumn to keep from starving during the late autumn, all of winter, and early spring.
Shipment / Storage / Risk factors
Usually shipped in bags or cartons. Used for eating or for extraction of oil. Liable to mould damage and splitting, which may be due to natural causes. Splitting may be caused by late rains prior to the harvesting of the nuts or through being shipped in a damp condition; mould subsequently forming in the cavities. This mould may develop after shipment, during transit. Nuts and kernels are similarly affected by moisture.
Nuts and kernels are particularly susceptible to shrinkage and loss in weight, the degree of which varies considerably according to the year of the crop. Liable to infestation, which can in some cases be avoided by fumigation before shipment. Older crops are specially prone to damage by weevil and may become rancid. The crop year is an important point for the surveyor’s consideration. It is not uncommon for old season’s nuts to be mixed when the new season’s shipment takes place, and when dealing with questions of transit damage this possibility should not be overlooked.
Some nuts and kernels are liable to heat and ferment, particularly if shipped in damp condition.
The most favourable travel temperature range for hazelnuts is 2 -4°C. Travel temperatures of approx. 5 - 25°C are also feasible (depending on journey length), so it is not absolutely necessary for the product to be transported as chilled goods.
Dried walnuts may be kept for up to 12 months at temperatures of -3 - 0°C, while fresh walnuts may only be kept for a very short time.