GAZ (1)

 

GAZ, common term in Persian for several species of the genera Tamarix (desert trees) and Astragalus (spiny shrubs of gavan); also the name of a confection made with the sweet exudate (gaz-angobīn) produced on Astragalus. This article deals only with the exudate found on A. adscendens Boiss. and Haussk. and the candy made from it.

For tragacanth, an important product of other species of Astragalus, see KATĪRĀ. On the sweetish manna found on some oaks (Quercus mannifera) and called gaz-e ʿalafī, see BALŪṬ.

i. Gaz-angobīn.

ii. Candy.

 

i. GAZ-ANGOBĪN

A. adscendens (gavan-e gazī) is a very prickly, grayish-green, perennial shrub which grows up to 1 m in height, with diagonally ascending branches culminating in a flat crown 1 m or more in diameter. Indigeneous to the mountains southwest of Isfahan in central Persia, it was collected by Karl Haussknecht in 1870 and classified by Edmond Boissier in 1872 (II, p. 317; Ṯābetī, p. 42). It is the source of gaz-angobīn, the sweet exudate used to produce the popular Iranian confection known as gaz. The exudate is sometimes also referred to as gaz-e Ḵᵛānsār, after a town in the producing area.

While the history of gaz-angobīn dates back centuries, the consensus on its origins has, until recently, been split between those who saw it as the product of an insect and those who believed it to originate from the plant itself, like certain other mannas. The Persian scholar Bīrūnī (q.v.) has been cited as the earliest authority to refer to a manna-producing insect on a spiny plant species (apud Meyerhof). A historical survey by R. A. Donkin in 1980 shows that gaz-angobīn was noticed by western travelers during the 18th and 19th centuries. Other travelers reported that, according to local opinion, gaz-angobīn was an insect product (Gmelin, IV, p. 288; Malcolm, II, 526 n.). Captain Edward Frederick, a traveler to Persia in 1813, made the following comments regarding his experiences with gaz-angobīn: “The shrub on which the gez is found is called gavan with a striking resemblance to the broom,…and underneath we saw the gez spread all over the tender branches like white uneven threads, with innumerable little insects creeping slowly about. These little creatures appeared to derive their subsistence from the leaves and young bark of the bush they inhabit. The inhabitants of Kunsar were decidedly of opinion that this curious substance is the production of these diminutive animals, as neither the insects nor the gez are found on any other tree in the neighborhood; I looked upon [gaz] as unquestionably an animal production.” However, Mīrzā Jaʿfar Ṭabīb, a Persian physician residing in London in 1819, referring to Frederick’s conclusions, commented that gaz was the name of trees that supposedly belong to the genus Tamarix, and that “it is the universal opinion in Persia that all these varieties are exudations from the trees on which they are found, and not the work of insects” (Tabeeb, p. 268). Frederick’s findings were not generally accepted for another 150 years.

Gradually, observers became aware that gaz was indeed the product of the insect, with A. adscendens simply acting as a host. M. Ṣāneʿī and M. Esmāʿīlī visited the site in 1980 and reported that “the insect, in its nymphal stage, exudes a soft, colorless, thread-like substance from the anus onto the plant” (p. 1). They indicated that a detailed study of the insect was necessary to improve understanding of the process of gaz production. A. Naʿīm and E. Behdād (1988) subsequently investigated the biology of the insect in Ḵᵛānsār. They identified the insect as Cyamophila dicora Loginova and provided information on its life-cycle and morphology: Its eggs are placed in tandem alongside the main vein of fully-grown leaves, which then curl up around the vein. The nymphs begin feeding inside the rolled-up leaves before they are scattered over the plant during flowering. They can be seen between the sepals and petals, but not inside the corolla. The white, sticky, segmented strings of gaz are mostly secreted in the last instar stage. The segments indicate multiple excretions. The soft exudates harden, eventually detach from the nymph’s body, and remain in the foliage, mixed with the nymphs and often with the plant debris as well. The insect completes one generation in a year. In 1993, however, in a thorough review of the jumping plant-lice of Iran by D. Burckhardt and P. Lauterer, the gaz-producing insect was classified in the family Psyllidae, subfamily Arytaininae, and the genus Cyamophila (p. 833). Burckhardt and Lauterer’s study indicated that the specimens previously identified as C. dicora by Naʿīm and Behdād show the characteristic, entirely brownish forewings of C. astragalicola Gegechkori, while the forewings of C. dicora, by contrast, bear distinct apical brown patches. They therefore identified the gaz-producing insect as C. astragalicola.

The gathering of gaz-angobīn may begin in late August and continue until mid-October, depending on location and weather. The methods of its collection have remained unchanged for at least two centuries. Frederick wrote in 1819, “The men were furnished with a stick three-fourths of an inch in diameter and curved at the further extremity, which was covered with leather, and a kind of oval leathern bowl nearly three feet long and two broad with a handle to it, resembling an egg-shell cut in two longitudinally. Besides these, they had a sieve suspended from the right side, to free the gez from the insects and small pieces of leaf that generally fall with it when first beat from the bush. The bottom of the sieve was of coarse woolen cloth” (p. 255). The stick for beating the bush, which resembles a tennis racket, is locally called arbeh-kūdī. The oval collecting bowl is made of processed goat or sheep skin stretched over a wooden frame and is locally called seyleh. The gatherer holds the seyleh under the branches, strikes them rather gently with the stick and catches the tiny, threadlike gaz-angobīn particles, along with some plant debris and insects, in the seyleh. Then, he passes the material through the sieve and separates the gaz from the rest.

When the gaz of Ḵᵛānsār was abundant in the past, plants could be visited several times at intervals of a few days. During September, it was collected every third day; if repeated more often than that, the insects would become exhausted (Frederick, p. 256). While in the past one shrub could yield up to 20 or 30 grams of gaz-angobīn, in recent years it might require dozens of plants to yield that quantity. Since the egg-bearing leaflets fold lengthwise and form tubes, some gatherers have learned how to use them to make predictions about the gaz-producing capacity of plants a few weeks before the gathering season.

The plant is virtually an unlimited food source for the insect. The plant density is sufficiently high and not much footwork is required by the gaz gatherers. Seasonal fluctuation in the population of the insects, however, has a direct effect on gaz-angobīn production. Ṣāneʿī and Esmāʿīlī (p. 4) suggested that, early in spring, adult insects be transferred from high to low population areas, and the insects and seeds collected on the sieve during collection be carried in paper bags to the areas of lower gaz-angobīn production. Rainfall and strong wind during the collecting season will also have adverse effects on gaz-angobīn collection.

Iranian researchers have investigated the physico-chemical properties of gaz-angobīn (Nīk-nežād; Āʾīnačī, Nīk-nežād, and Ṣāneʿī; Hāšemīya Anārakī, table 2). It is free of nitrogen, sulfur, tannin, alkaloids, and halogens (Br, Cl, I). A 1 percent water solution has a pH of 5.5 and rotates polarized light to the right. Gaz-angobīn is originally white or cream-colored, while it may seem greenish or brownish-yellow in bulk depending on impurities. It is hydrophilic, soft, and very sticky under normal conditions, breakable when dry, and readily soluble in water and alcohol. Gaz-angobīn is very sweet due to its high fructose content, about 40 percent, comparable to honey (Crane, p. 398).

Gaz-angobīn has been produced locally and consumed nationally in Iran for centuries. Demand for this substance considerably exceeds the available supply. Taking advantage of the increased knowledge about it in recent years and adopting recommended practices should help increase the production of this popular sweet substance. Some major recommendations include protecting gaz-producing areas from grazing animals, controlling the natural enemies of the gaz-producing insect, keeping bee activities away from gaz plant communities, and granting the rights of gaz collection to the local inhabitants.

PLATE I. Astragalus adscendens Boiss and Haussk, Leguminosae.

PLATE II. Gaz plants at the foot of the Ḵᵛānsār hills. Gaz gatherers can be seen in the background.

PLATE III. Gaz gatherers with their tools at the foot of the Ḵᵛānsār hills.

PLATE IV. Gathering gaz: tapping the plant and collecting gaz in the leather bowl.

 

Bibliography:

Y. Āʾīnačī, A. Nīk-nežād, and M. Ṣāneʿī, “Gaz-e Ḵonsār: manbaʿ-e ḡanī-e frūktūz/Gaz of Ḵunsar: A Rich Source of Fructose,” Majalla-ye Dāneškada-ye dārūsāzī, Dānešgāh-e Tehrān/Journal of College of Pharmacy of the University of Tehran 8, 1976, pp. 3-8.

E. P. Boissier, Flora Orientalis, 5 vols., Geneva and Basle, 1872.

D. Burckhardt and P. Lauterer, “The Jumping Plant-Lice of Iran (Homoptera, Psylloidea),” Revue Suisse de Zoologie 100, 1993, pp. 829-98. Chardin, III, pp. 295-96.

E. Crane, Bees and Beekeeping: Science, Practice, and World Resources, Ithaca, N. Y., 1990, p. 389.

Curzon, Persian Question, II, p. 502.

R. A. Donkin, Manna: An Historical Geography, The Hague and Boston, 1980 (with extensive references to mentions of gaz in European travel literature).

E. Frederick, “Remarks on the Substance called Gez or Manna found in Persia and Armenia,” Transaction of Literary Society of Bombay 1, 1819, pp. 251-58.

S. G. Gmelin, Reise durch Russland zur Untersuchung der drey Naturreiche III: Reise durch das nördliche Persien..., St. Petersburg, 1774, pt. 4, p. 288.

B. Grami, “Gaz-e Kᵛānsār,” College of Agriculture, Isfahan University of Technology, 1981, pp. 1-21.

Idem, “Gaz of Khunsar: The Manna of Persia,” Economic Botany 52, 1998, pp. 183-91.

A. Hāšemīya Anārakī, “Barrasī-e šīmīāʾī-e mawādd-e ālī-e ḡayr-e qandī-e gaz-e Ḵonsār/ Non-Saccharide Organic Compounds in Gaz of Khunsar,” Ph.D. diss., College of Pharmacy, University of Isfahan, 1976.

J. Malcolm, The History of Persia, London, 1815.

M. Meyerhof, “The Earliest Mention of a Manniparous Insect,” Isis 37, 1947, pp. 31-36.

M. Ṣāneʿī Šarīʿat-panāhī and M. Esmāʿīlī, “Gozāreš barrasī-e masʾala-ye gaz-e Ḵonsār dar ostān-e Eṣfahān,” Tehran, Mehr 1359 Š./1980 (hand-written report to the Faculty of Agriculture, University of Tehran).

ʿA. Naʿīm and E. Behdād, “Barrasī-e zīst-šenāsī-e pesīl-e gaz (Cyamophila dicora Loginova) dar marāteʿ-e Ḵonsār/The Biology of ‘Gaz Psyllid’ in Iran,” Našra-ye āfāt o bīmārīhā-ye gīāhī/Applied Entomology and Phytopathology 55, 1988, pp. 111-21.

Schlimmer, p. 358. Mirza Jiafar Tabeeb (Mīrzā Jaʿfar Ṭabīb), “Gezangabeen, or Persian Manna,” Asiatic Journal 7, 1819, p. 268.

A. Nīk-nežād, “Mannhā-ye Īrān/The Mannas of Iran,” Ph.D. diss., College of Pharmacy, University of Isfahan, 1976.

Ḥ. Ṯābetī, Deraḵtān o deraḵtčahā-ye Īrān, Tehran, 1344 Š./1965.

(BAHRAM GRAMI)

 

ii. CANDY

The candy gaz, made mainly in Isfahan, is prepared from high-quality gaz-angobīn from Ḵᵛānsār. To prepare gaz, gaz-angobīn is dissolved in an equivalent amount of water and brought to a boil over low heat. After straining the solution to remove the impurities, egg whites are added, and the mixture is beaten with a whisk and strained again. Then sugar is added to the solution and it is heated until the mixture reaches the consistency of a paste (Moʿīn, III, p. 3299). To this mixture, shelled pistachio nuts or almonds are added, and the mixture is then shaped into small, flat, round pieces three to four inches in diameter and about three-fourths of an inch in thickness or bite-size, uniform pieces and allowed to cool. The gaz is usually kept or packed in loose white flour to prevent it from being affected by moisture and sticking together. The precise preparation procedures, ingredients, and measurements differ from confectioner to confectioner, each guarding his recipe as a trade secret, which is handed down from one generation to the next. The candy and its unusual property of being both adhesive and brittle was noted with interest by the 19th century traveler Edward Frederick.

 

Bibliography:

Moḥammad-Ḥosayn ʿAqīlī Ḵorāsānī Šīrāzī, Maḵzan al-adwīa, Calcutta, 1844; repr. Tehran, 2535 (1355) Š./1976, p. 747.

E. Frederick, “Remarks on the Substance called Gez or Manna found in Persia and Armenia,” Transaction of Literary Society of Bombay 1, 1819, pp. 251-58.

M. Moʿīn, Farhang-e fārsī, 6 vols., Tehran, 1342-52 Š./1963-73.

Moḥammad Moʾmen Ḥosaynī (Ḥakīm Moʾmen), Toḥfat al-moʾmenīn (Toḥfa-ye Ḥakīm Moʾmen), Tehran, n.d., p. 725.

C. C. Rice, Persian Women and Their Ways, London, 1923; repr. Tehran, 1976, p. 183.

(M. R. GHANOONPARVAR)

(B. Grami, M. R. Ghanoonparvar)

Originally Published: December 15, 2000

Last Updated: February 3, 2012

This article is available in print.
Vol. X, Fasc. 4, pp. 348-352