Difference between revisions of "Nut (fruit)"

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Hazelnuts from the Common Hazel
Chestnut

A nut can be either a seed or a fruit.

Botanical definitions

A nut in botany is a simple dry fruit with one seed (rarely two) in which the ovary wall becomes very hard (stony or woody) at maturity, and where the seed remains unattached or unfused with the ovary wall. Most nuts come from pistils with inferior ovaries (see flower) and all are indehiscent (not opening at maturity). True nuts are produced, for example, by some plants — families of the order Fagales.

Order Fagales

Culinary definition and uses

A nut in cuisine is a much less restrictive category than a nut in botany, as the term is applied (or misapplied, depending upon the viewpoint) to many seeds that are not true nuts. Any large, oily kernel found within a shell and used in food may be regarded as a nut. 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 them from starving during the winter and early spring.

Nuts, including both tree nuts and peanuts, are among the most common food allergens.[1]

Korean Pine pine nuts — unshelled, and shell, above; shelled, below

Some fruits and seeds that are nuts in the culinary sense but not in the botanical sense:

See also: List of edible seeds

Advocacy of nuts by John Harvey Kellogg

Bowl of mixed nuts

In 1920, John Harvey Kellogg, the medical director of the Battle Creek Sanitarium wrote an article entitled "Nuts May Save the Race" within his book The Itinerary of a Breakfast. Kellogg's article promoted nuts as an ideal source of protein, particularly after the first world war and the shortage of meat sources throughout Europe and America. Kellogg explains that nuts were primarily considered to be a luxury in society, but should take the place of meat as a main source of protein in the American diet. The principal reason nuts were not prominent in the American diet is because of the idea that nuts were highly indigestible and that they were relatively expensive. However, within his article, Kellogg argues that there is no scientific proof of their indigestibility and that the price of nuts is comparable to the price of meat. (J.H. Kellogg, 1920, 173–176).

Kellogg presents the advantages of a nut diet, promoting their benefits to the American population. First he argues that unlike meat, nuts are free from waste products. Nuts are also free from bacteria that cause things to easily spoil, and they last for a long time. They are free from parasites, like tapeworm and trichnae, and do not pose a great threat to consumers. (Kellogg 175).

In a section of his article on nuts, Kellogg made a plea to the American population, writing "Something Must Be Done." He argued that the meat supply is rapidly diminishing, and that nuts could be the only "future sustenance of the race." He predicted, correctly, that nut growing was going to become one of the most important agricultural industries, and that nuts were truly one of the earth's finest bounties (Kellogg 200–203).

Kellogg's article and his promotion of a strictly vegetarian diet led to a new appreciation of nuts and nut butters as a perfect source of protein in an American diet.

Nut allergy

Main article: Nut Allergy

Allergy to nuts is a relatively common and often very serious problem. For people with nut allergy, exposure to surprisingly small amounts of nut fragments (e.g. minor cross-contamination of otherwise nut-free products in a food processing factory) can cause fatal anaphylactic shock which has led to their banning on some school premises.

Allergy to peanuts is the most common; some evidence suggests that some peanut allergies may be related to the use of peanuts in baby foods; if given to very young children who are not yet able to digest all the components of peanuts fully, the body will then react against those components.Template:Fact

It has been reported that the processes that increase the flavour and shelf-life of peanuts, namely maturation, roasting and curing, increase their allergenic properties and that this may be applicable to other nut types also. [2]

As the peanut is a member of the pea family unrelated to other nuts, individuals with allergies to peanuts may not be allergic to other nuts, and those with allergies to other nuts may not be allergic to peanuts. A common term applied to nuts, used to distinguish them from peanuts, is "tree nuts".

Nutritional benefits

A graph detailing the nutritional properties of nuts and oily seeds.

Several epidemiological studies have revealed that people who consume nuts regularly are less likely to suffer from coronary heart disease. Recent clinical trials have found that consumption of various nuts such as almonds and walnuts can lower serum LDL cholesterol concentrations. Although nuts contain various substances thought to possess cardioprotective effects, scientists believe that their fatty acid profile is at least in part responsible for the hypolipidemic response observed in clinical trials.

In addition to possessing cardioprotective effects, nuts generally have a very low glycemic index (GI). Consequently, dietitians frequently recommend nuts be included in diets prescribed for patients with insulin resistance problems such as diabetes mellitus type 2.

One study found that people who eat nuts live two to three years longer than those who do not. However, this may be because people who eat nuts tend to eat less junk food. [3]

Other uses

The "nut" of the horse-chestnut (Aesculus hippocastanum), is also known as a conker. Conkers are inedible, due to the presence of the toxic glucoside aesculin, but are collected and used in an old children's game, also known as conkers, in which a nut is threaded onto a strong cord and then each child attempts to break their opponent's conker by hitting it with their own. A related species, Aesculus californica, was formerly eaten by the Native Americans of California in times of famine. It must be leached to remove the toxic constituents before eating.

References

  1. ↑ "Common Food Allergens". The Food Allergy & Anaphylaxis Network. Retrieved on 2007-06-24.
  2. ↑ Nut Grower's Guide: The Complete Handbook for Producers and Hobbyists by Jennifer Wilkinson, Landlinks Press, 2005. quoting Soutter, V. (2004). "Allergic reactions to nuts". Australian Nutgrower 18(3), 38.
  3. ↑ "ABC News: The Places Where People Live Longest". URL accessed January 18, 2007.

Kellogg, John H. "Nuts May Save the Race." The Itinerary of Breakfast. New York: Funk & Wagnalls Company, 1920. 165–203.

External links

Template:Commonscat Template:Cookbook

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