Almond

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Read about Almond in the Standard Cyclopedia of Horticulture 

Almond. A name given to the tree and fruit of Prunus Amygdalus, Baill. (Amygdalus communis, Linn.), of the Rosacea. It is also applied to certain dwarf ornamental trees or bushes, as flowering almond (see Prunus).

The almond has been cultivated from time immemorial. It is thought to be native to the Mediterranean basin. Some inquirers have supposed it to be the original of the peach, but this idea is evidently untenable. The flowers are peach-like and handsome. The almond nut of commerce is the pit or stone of a peach-like fruit. The fleshy part, which is so thick and edible in the peach, is thin and hard, and it splits at maturity. There are two general tribes or races of almonds,—the bitter and the sweet. The former has a bitter kernel, which is used in the manufacture of flavoring extracts and prussic acid. It is grown mostly in Mediterranean countries. Of the sweet or edible almonds, there are two classes,—the hard-shell and the soft-shell. The former is of little value, and is not grown to any extent. The soft-shell type produces the edible almonds of commerce. Some of the thinnest-shelled forms are known as Paper-shells. It was once thought that almond-growing could be successfully practised in the peach-growing sections of the East, but late spring frosts, and other difficulties, have caused the effort to be abandoned commercially. Individual almond trees are occasionally seen, and they frequently bear profusely. They are nearly as hardy as the peach. The commercial cultvation of the almond on this continent is confined to western America, and the remainder of this account is therefore written from the Californian standpoint.

Almond-growing in California has received the attention of horticulturists for half a century, and during the whole of its course the industry has been marked by vicissitudes which, it must be admitted, are not yet ended. Two chief sources of difficulty are now clearly discerned to have attended the effort from its beginning, and present knowledge may enable planters to avoid, in the future, errors that have led to much disappointment and loss—the vestiges of which still encumber the ground, though clearing is proceeding rapidly. Thus far the almond tree has yielded more firewood than any other single fruit tree which has been largely planted in California, and yet planting has continued, planting and uprooting keeping pace, so that about 1,500,000 trees are annually reported by the county assessors, of which number about two-thirds may be counted of bearing age. The California almond product for a series of years is estimated as follows:

1905 2,125 tons

1906 900 "

1907 750 "

1908 3,000 "

1909 1,650 tons

1910 2,750 "

1911 1,700 "

1912 3,000 "

Irregularity in production is mainly due to the occurrence or absence of spring frosts. In spite of these facts, the almond will remain an important California product, through the satisfactory performance of trees enjoying favorable environment, which is being generally accepted as a safe guide for current planting.

The two chief sources of failure with the almond are the sterility of many varieties without cross-pollination, and the extreme propensity of the tree for early blooming, with the consequent destruction of the bloom or the young fruit by temperature very little below the freezing point. These two evils have been singularly associated historically, and only lately have they been shown to be independent factors and both of them demanding the closest attention from planters. At first it was thought that the wide planting of self-sterile varieties by themselves was the cause of disappointment, because, after years of chopping-out or grafting-over old unproductive trees to the Prune d'Agen, for which it is an excellent stock, it was observed, by chance, that the Languedoc variety adjacent to Drake's seedling, of local origin, was heavily laden with nuts when it was sterile without such association. Attention was then directed to the growth of seedlings, and a large lot of seedlings of the bitter almond, grown by A. T. Hatch, exhibited such satisfactory bearing habit and such striking variation toward new types of the soft-shell sweet almond that the growth of new selected California seedlings was seized upon as a panacea for the previously experienced troubles with the almond. These new varieties were conceived to be not only self-fertile but hardy, and large plantations were made without due regard to the frosty character of the locations. Low valley lands of great area, and some extent of high plateaux, were planted. Fine, large trees grew only to lose their crops year after year by frosts from February to April, until the growers cast the trees upon the wood-pile. As a deduction of the experience of several decades, we have arrived at what seems now to be the proper conception of the situation of the almond in California, which is that the most prolific varieties must be chosen, must be associated for purposes of cross-pollination, and must be planted in places of least liability to frost. There is a factor of some moment in the late-blooming habit of some varieties, which will be considered presently.

The soil best suited to the almond is a light, well- drained loam. The tree makes a strong and rapid root-growth, and is more tolerant of drought than any other of our leading deciduous fruit trees. For this reason, as well as to avoid frost, it is often desirable to place the almond on the higher and drier lands of the valley— providing the soil is not heavy and too retentive of surplus water in the rainy season. The root is most intolerant of standing water, and will quickly die if exposed to it. Because of its thrift in light, dry soils, the almond root is used rather largely as a stock for the Prune d'Agen, and to some extent for the peach in the dry valleys.

Almond trees are grown by budding into seedlings grown from either the sweet or the bitter hard-shell almonds, the bud being set during the first summer's growth of the seedling, and then either planted out as a dormant bud the following winter or allowed to make one season's growth on the bud in the nursery. The tree grows so rapidly, both in root and top, that only yearling trees are used.

At transplanting, the young trees are cut back so as to form a low head with only about a foot of clear trunk. They are allowed to make free growth during the following summer, and in the following winter are cut back so as to encourage branching on the main limbs within a foot of their attachment to the trunk. At the same time, the branches are reduced to four or five in number, symmetrically arranged around the stem and at good distance from each other, so that they shall not unduly crowd each other as they enlarge. Another full growth during the following summer and another cutting back the following winter give the trees the vase-form on the outside, with enough interior branches to fill the inside of the tree without crowding. Thus the tree is systematically pruned after each of its first two years' growth in the orchard. After that, shortening-in of the branches usually ceases, and the third summer's growth is allowed to stand for fruit-bearing, with only thinning-out of growth to prevent crowding. This thinning-out has to be done from time to time in later years, otherwise the tree becomes too thick, and interior branches dwindle for lack of light. The amount of thinning varies in the different climates of the state: the greater the heat, the denser the tree for its own protection. With the proper adjustment of heat and light, fresh bearing wood may be encouraged in the lower part of the tree, otherwise it becomes umbrella-shaped, with the fruit wood at the top and bare poles below.

The almond is the earliest bloomer of our common fruits. It puts forth flowers sometimes as early as January, but the usual date is about February 10 for the earliest bloomers in the warmer parts of the state, with the later bloomers at intervals thereafter until April 1. Records of full bloom of a number of varieties widely grown in California, which have been kept at the University of California substation, situated in the Sierra foot-hill region, show the following succession: Commercial, February 27; Sultana and Paper-shell, March 10; King and Marie Duprey, March 11; IXL, March 12; Languedoc, March 19; Nonpareil, March 20; Routier Twin, March 24; Pistache, March 25; Drake and Texas, April 2. Obviously the late bloomers have greater chance of escaping frost, and there is at present some disposition to make this a consideration in selecting varieties for planting. The dates just given show an extreme variation in time of blooming. Some years the intervals are much shorter, but the relation seems to be constant. The crop ripens from August 15 to October 1, accorcding to locality. Early maturity does not follow early blooming—that is, as with other fruits, the first to bloom are not necessarily the first to ripen.

Not less than twenty-five varieties of almonds have been grown to a greater or less extent in California. Varieties of foreign origin have almost wholly given place to selected seedlings of local origin, and of these a very few constitute the main crop at present. These are named in the order of their acreage, as follows: Nonpareil, Ne Plus Ultra, IXL, Drake, Texas Prolific, Languedoc. Of these, the first three occupy not less than three-fourths of the acreage.

In handling the crop, the local climate modifies methods somewhat, and the growth-habit is also involved. In regions very free from atmospheric humidity in the summer, the hull opens readilv and discloses a clean, bright nut, which can be marketed without treatment. Where this is not the case, and the nut is more or less discolored, bleaching in the fumes of sulfur has to be practised. The nut must be dry before sulfuring, or the fumes will penetrate and injure the flavor of the kernel. Sulfured nuts also lose largely in power of germination. The practice is to gather the nuts, dry for a few days in the sun, then spray with water very lightly or with a jet of steam, so that only the surface of the shell is moistened, and then sulfur, and a light color can be secured without penetration of the fumes. The nuts can usually be gathered from the ground as they naturally fall, or can be brought down by shaking or the use of light poles. Some varieties are more easily harvested than others, and the same variety falls more readily in some localities than in others. A greater or less percentage, according also to variety and locality, will have adhering hulls, and for clearing them, locally-invented machines, called almond-hullers, are used. Early rains in some localities are apt to stain the nuts. Such stains cannot be removed by sulfuring, and the nuts have to be crushed and the product marketed as kernels for the use of confectioners. Machinery is also used for this operation, and a considerable fraction of the product reaches the market in this form because of the demand for candied and salted almonds.

The standard of excellence in the almond, from a commercial point of view, as learned by the experience of California producers, is that the kernel must be as smooth, symmetrical and plump as possible. The twinning of kernels, welcome as it may be to searchers for philopenas, results in misshapen kernels, which are very objectionable to the confectioners, who are very large users of almonds. Constancy to single kernels is therefore a good point in a variety.

Large proportion of kernel to shell by weight is also, obviously, an important point to almond-buyers. At the same time, the shell may be so reduced in strength as to break badly in shipping in sacks and in subsequent handling. Incomplete covering also exposes the kernel to the sulfur and to loss of flavor. The ideal is such degree of thinness of shell as can be had with complete covering of the kernel and durability in handling.

Careful comparison of the proportion of kernel weight to gross weight of the popular California varieties, as compared with a leading imported variety, was made by a committee of the California Horticultural Society, with the following result: From one pound of each of the following varieties the net weight of kernels in ounces was: Imported Tarragona, 6 3/5; California Languedoc, 7 1/2; El Supremo, 7 1/2, Drake, 8 3/4; IXL, 9; Commercial, 9 1/4; La Prima, 9 1/2; Princess, 9 1/2; Ne Plus Ultra, 10; King, 10; Paper-shell, 11; Nonpareil, 11 to 13.


The above text is from the Standard Cyclopedia of Horticulture. It may be out of date, but still contains valuable and interesting information which can be incorporated into the remainder of the article. Click on "Collapse" in the header to hide this text.



Almond
Almonds in and out of shell
Almonds in and out of shell
Plant Info
Scientific classification
Kingdom: Plantae
Division: Magnoliophyta
Class: Magnoliopsida
Order: Rosales
Family: Rosaceae
Subfamily: Prunoideae
Genus: Prunus
Subgenus: Amygdalus
Species: P. dulcis

Binomial name
Prunus dulcis
(Mill.) D. A. Webb

Template:Nutritionalvalue

The almond (Prunus dulcis, syn. Prunus amygdalus, or Amygdalus communis) is a small deciduous tree belonging to the subfamily Prunoideae of the family Rosaceae; an almond is also the fruit of this tree. The plant is classified with the peach in the subgenus Amygdalus within Prunus, distinguished from the other subgenera by the corrugated seed shell.

The sweet fleshy outer covering of other members of Prunus, such as the plum and cherry, is replaced by a leathery coat called the hull, which contains inside a hard shell the edible kernel, commonly called a nut. In botanical parlance, the reticulated hard stony shell is called an endocarp, and the fruit, or exocarp, is a drupe, having a downy outer coat.

The tree is a native of southwest Asia. The domesticated form can ripen fruit as far north as the British Isles. It is a small tree, growing to 4-9 m tall. The leaves are lanceolate, 6-12 cm long, and serrated at the edges. The flowers are white or pale pink, 3-5 cm diameter with five petals, produced before the leaves in early spring.

Origin and history

The wild form of domesticated almond grows in the Mediterranean region in parts of the Levant; almonds must first have been taken into cultivation in this region. The fruit of the wild forms contains glycoside amygdalin, "which becomes transformed into deadly Prussic acid (Hydrogen cyanide) after crushing, chewing, or any other injury to the seed."[1] Before cultivation and domestication occurred, wild almonds were harvested as food and doubtless were processed by leaching or roasting to remove their toxicity.

However, domesticated almonds are not toxic; Jared Diamond argues that a common genetic mutation causes an absence of glycoside amygdalin, and this mutant was grown by early farmers, "at first unintentionally in the garbage heaps and later intentionally in their orchards."[2] Zohary and Hopf believe that almonds were one of the earliest domesticated fruit-trees due to "the ability of the grower to raise attractive almonds from seed. Thus in spite of the fact that this plant does not lend itself to propagation from suckers or from cuttings, it could have been domesticated even before the introduction of grafting."[3] Domesticated almonds appear in the Early Bronze Age (3000–2000 BC) of the Near East, or possibly a little earlier. A well-known archaeological example of almond is the fruits found in Tutankhamun's tomb in Egypt (c. 1325 BC), probably imported from the Levant.[4]

Unripe almond on tree

Production

Global production of almonds is around 1.5 million tonnes, with a low of 1 million tonnes in 1995 and a peak of 1.85 million tonnes in 2002 according to Food and Agriculture Organization (FAO) figures (pdf file). Major producers include Greece, Iran, Italy, Morocco, Portugal, Spain, Syria, Turkey, and the world's largest producer: The United States. In Spain, numerous commercial cultivars of sweet almond are produced, most notably the Jordan almond (imported from Málaga) and the Valencia almond. In the United States, production is concentrated in California, with almonds being California's sixth leading agricultural product and its top agricultural export. California exported almonds valued at 1.08 billion dollars in 2003, about 70% of total California almond crop.

Diseases

Main article: List of almond diseases

Pollination

The pollination of California's almonds is the largest annual managed pollination event in the world, with close to one million hives (nearly half of all beehives in the USA) being trucked in February to the almond groves. Much of the pollination is managed by pollination brokers, who contract with migratory beekeepers from at least 38 states for the event.

Flowering branch of an almond tree

Sweet and bitter almonds

There are two forms of the plant, one (often with white flowers) producing sweet almonds, and the other (often with pink flowers) producing bitter almonds. The kernel of the former contains a fixed oil and emulsion. As late as the early 20th century the oil was used internally in medicine, with the stipulation that it must not be adulterated with that of the bitter almond; it remains fairly popular in alternative medicine, particularly as a carrier oil in aromatherapy, but has fallen out of prescription among doctors.

The bitter almond is rather broader and shorter than the sweet almond, and contains about 50% of the fixed oil which also occurs in sweet almonds. It also contains the enzyme emulsin which, in the presence of water, acts on a soluble glucoside, amygdalin, yielding glucose, cyanide and the essential oil of bitter almonds or benzaldehyde. Bitter almonds may yield from 6 to 8% of Hydrogen cyanide. Extract of bitter almond was once used medicinally but even in small doses effects are severe and in larger doses can be deadly;[5] the prussic acid must be removed before consumption.

The nut of the tree has also been used as a preventative for alcohol intoxication. Folklore claims that almonds are poisonous for foxes.

Almond blossom giving way to leaf shoots

Almond oil

"Oleum Amygdalae," the fixed oil, is prepared from either variety of almond and is a glyceryl oleate, with a slight odor and a nutty taste. It is almost insoluble in alcohol but readily soluble in chloroform or ether. It may be used as a substitute for olive oil.

The sweet almond oil is obtained from the dried kernel of the plant. This oil has been traditionally used by massage therapists to lubricate the skin during a massage session, being considered by many to be an effective emollient.

Almond syrup

Historically, almond syrup was an emulsion of sweet and bitter almonds usually made with barley syrup (orgeat syrup) or in a syrup of orange-flower water and sugar.

Grocer's Encyclopedia notes that "Ten parts of sweet almonds are generally employed t o three parts of bitter almonds", however due to the cyanide found in bitter almonds, modern syrups generally consist of only sweet almonds. Template:Grocers

Culinary uses

Smoked and salted almonds

While the almond is most often eaten on its own, raw or toasted, it is used in some dishes. It, along with other nuts, is often sprinkled over desserts, particularly sundaes and other ice cream based dishes. It is also used in making baklava and nougat. There is also almond butter, a spread similar to peanut butter, popular with peanut allergy sufferers and for its less salty taste.

The sweet almond itself contains practically no carbohydrates and may therefore be made into flour for cakes and biscuits for low carbohydrate diets or for patients suffering from diabetes mellitus or any other form of glycosuria. A standard serving of almond flour, 1 cup, contains 20 grammes of carbohydrates, of which 10 g is dietary fibre, for a net of 10 g of carbohydrate per cup. This makes almond flour very desirable for use in cake and bread recipes by people on carbohydrate-restricted diets.

Almonds can be processed into a milk substitute simply called almond milk; the nut's soft texture, mild flavour, and light colouring (when skinned) make for an efficient analog to dairy, and a soy-free choice, for lactose intolerant persons, vegans, and so on. Raw, blanched, and lightly toasted almonds all work well for different production techniques, some of which are very similar to that of soymilk and some of which actually use no heat, resulting in "raw milk" (see raw foodism).

Sweet almonds are used in marzipan, nougat, and macaroons, as well as other desserts. Almonds are a rich source of Vitamin E, containing 24 mg per 100 g.[6] They are also rich in monounsaturated fat, one of the two "good" fats responsible for lowering LDL cholesterol.

The Marcona variety of almond, which is shorter, rounder, sweeter, and more delicate in texture than other varieties, originated in Spain and is becoming popular in North America and other parts of the world.[7] Marcona almonds are traditionally served after being lightly fried in oil, and are also used by Spanish chefs to prepare a dessert called turrón.

In China, almonds are used in a popular dessert when they are mixed with milk and then served hot. In Indian cuisine, almonds are the base ingredient for pasanda-style curries.

Cultural aspects

Almond flowers
Almond tree in Spain.

The almond is highly revered in some cultures.

The tree grows in Syria and Israel, and is referred to in the Bible under the name of "Shaqued", meaning "hasten", or the literal Hebrew meaning "Awakening One", an appropriate name since the Almond tree is one of the first trees to flower at the close of winter, around late January/early February in Israel. The application of "Shaqued" or "hasten" to the almond is similar to the use of the name "May" for the hawthorn, which usually flowers in that month in Britain. Among the Hebrews it was a symbol of watchfulness and promise due to its early flowering, symbolizing God's sudden and rapid redemption of His people after a period when he seems to have abandoned them; in Jeremiah 1:11-12, for instance. In the Bible the almond is mentioned ten times, beginning with Genesis 43:11, where it is described as "among the best of fruits". In Numbers 17 Levi is chosen from the other tribes of Israel by a rod that brought forth almond flowers. According to tradition, the rod of Aaron bore sweet almonds on on e side and bitter on the other; if the Israelites followed the Lord, the sweet almonds would be ripe and edible, but if they were to forsake the path of the Lord, the bitter almonds would predominate. The almond blossom supplied a model for the menorah which stood in the Holy Temple, "Three cups, shaped like almond blossoms, were on one branch, with a knob and a flower; and three cups, shaped like almond blossoms, were on the other...on the candlestick itself were four cups, shaped like almond blossoms, with its knobs and flowers" (Exodus 25:33-34; 37:19-20). Similarly, Christian symbolism often uses almond branches as a symbol of the Virgin Birth of Jesus; paintings often include almonds encircling the baby Jesus and as a symbol of Mary.

The word "Luz", which occurs in Genesis 30:37, and which some translations have as "hazel", is supposed to be another name for the almond. In India, consumption of almonds is considered to be good for the brain, while the Chinese consider it a symbol of enduring sadness and female beauty.

Possible health benefits

Edgar Cayce, a man regarded as the father of American holistic medicine, also highly favored the almond. In his readings, Cayce often recommended that almonds be included in the diet. Claimed health benefits include improved complexion, improved movement of food through the colon and the prevention of cancer.Template:Fact Recent research associates inclusion of almonds in the diet with elevating the blood levels of high density lipoproteins and of lowering the levels of low density lipoproteins. [8][9]

In many Asian cultures almonds are thought to help one's memory, though there currently is no clinical study to reject or support this claim.Template:Fact

Etymology

The word 'almond' comes from Old French almande or alemande, late Latin amandola, derived through a form amingdola from the Greek amugdale (cf Amygdala), an almond. The al- for a- may be due to a confusion with the Arabic article al, the word having first dropped the a- as in the Italian form mandorla; the British pronunciation ar-mond and the modern Catalan ametlla and modern French amande show the true form of the word.

See also

References

  1. A picture of the desiccated fruits from Tutankhamun's tomb can be found in Daniel Zohary and Maria Hopf, Domestication of plants in the Old World, third edition (Oxford: University Press, 2000), p. 186
  2. Jared Diamond, Guns, Germs, and Steel: The Fates of Human Societies (New York: Norton, 1999), p. 118.
  3. Zohary and Hopf, Domestication, p. 187
  4. A picture of the desiccated fruits from Tutankhamun's tomb can be found in Zohary and Hopf, Domestication, p. 188
  5. Cantor, Doug; Fleischer, Jeff; Green, John and Israel, David L (July/August 2006). "The Fruit of the Matter". mental floss 5 (4): 12. 
  6. White G. "Vitamin E and Minerals: Nutrition from Nuts." AllAboutVision.com. Retrieved August 20, 2006.
  7. Marcona almonds
  8. Almonds and cholesterol at scienceblog.com
  9. Positive effect of almonds on blood lipids at the Journal of the Americal College of Nutrition

External links

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