
Donkey-hide gelatin or ass-hide glue () is
gelatin
Gelatin or gelatine () is a translucent, colorless, flavorless food ingredient, commonly derived from collagen taken from animal body parts. It is brittle when dry and rubbery when moist. It may also be referred to as hydrolyzed collagen, coll ...
obtained from the skin of the donkey (''Equus asinus'') by soaking and
stewing
A stew is a combination of solid food ingredients that have been cooked in liquid and served in the resultant gravy. Ingredients can include any combination of vegetables and may include meat, especially tougher meats suitable for slow-cooking, ...
. It is used as an ingredient in the
traditional medicine of China,
where it is called ejiao (), meaning "gelatin of
Dong'e County
Dong'e County () falls under the jurisdiction of Liaocheng Prefecture-level city, in the Shandong Province of China. It is located on the left (northern) bank of the Yellow River, some upstream from the provincial capital Jinan.
The county is r ...
".
The gelatin is produced in several coastal provinces of China, including
Jiangsu
Jiangsu is a coastal Provinces of the People's Republic of China, province in East China. It is one of the leading provinces in finance, education, technology, and tourism, with its capital in Nanjing. Jiangsu is the List of Chinese administra ...
,
Zhejiang
)
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, translit_lang1_info2 = ( Hangzhounese) ( Ningbonese) (Wenzhounese)
, image_skyline = 玉甑峰全貌 - panoramio.jpg
, image_caption = View of the Yandang Mountains
, image_map = Zhejiang i ...
, and
Shandong
Shandong is a coastal Provinces of China, province in East China. Shandong has played a major role in Chinese history since the beginning of Chinese civilization along the lower reaches of the Yellow River. It has served as a pivotal cultural ...
. Shandong's
Dong'e County
Dong'e County () falls under the jurisdiction of Liaocheng Prefecture-level city, in the Shandong Province of China. It is located on the left (northern) bank of the Yellow River, some upstream from the provincial capital Jinan.
The county is r ...
is the source of the name "ejiao".
According to a ca. 1723 account by the French
Jesuit
The Society of Jesus (; abbreviation: S.J. or SJ), also known as the Jesuit Order or the Jesuits ( ; ), is a religious order (Catholic), religious order of clerics regular of pontifical right for men in the Catholic Church headquartered in Rom ...
Dominique Parrenin, there was a well in Dong'e which was normally kept closed and sealed, and which was only opened when water was taken to be used in preparation of ''ejiao'' for the emperor's court.
[ (This is a reprint; the original text was published in the first half of the 18th century. ''E ]xian
Xi'an is the list of capitals in China, capital of the Chinese province of Shaanxi. A sub-provincial city on the Guanzhong plain, the city is the third-most populous city in Western China after Chongqing and Chengdu, as well as the most populou ...
'' (for Dong'e) and ''Ejiao'' are transcribed ''Ngo-hien'' and ''Ngo-kiao'', under the transcription system then in use).
Manufacture
Li Shizhen
Li Shizhen (July 3, 1518 – 1593), courtesy name Dongbi, was a Chinese acupuncturist, herbalist, naturalist, pharmacologist, physician, and writer of the Ming dynasty. He is the author of a 27-year work, the '' Compendium of Materia ...
wrote in ''
Bencao gangmu
The ''Bencao gangmu'', known in English as the ''Compendium of Materia Medica'' or ''Great Pharmacopoeia'', is an encyclopedic gathering of medicine, natural history, and Chinese herbology compiled and edited by Li Shizhen and published in the ...
'' that ''ejiao'' is originally made from beef skin, but by his time, donkey had become the preferred choice. He describes the beef-gelatin of his time as poorly made and only suitable for gluing things.
According to
Parennin, the product was traditionally prepared during the late fall and winter (from after the harvest and until the beginning of March). It was supposed to be made from the skin of a recently killed well-nourished black
donkey
The donkey or ass is a domesticated equine. It derives from the African wild ass, ''Equus africanus'', and may be classified either as a subspecies thereof, ''Equus africanus asinus'', or as a separate species, ''Equus asinus''. It was domes ...
.
[ Since the supply of this material was rather limited, it was said that a large amount of "]fake
Fake or fakes may refer to:
Arts and entertainment Film and television
* The Fake (1927 film), ''The Fake'' (1927 film), a silent British drama film
* The Fake (1953 film), ''The Fake'' (1953 film), a British film
* Fake (2003 film), ''Fake'' (20 ...
" ejiao was also manufactured, using skins from mule
The mule is a domestic equine hybrid between a donkey, and a horse. It is the offspring of a male donkey (a jack) and a female horse (a mare). The horse and the donkey are different species, with different numbers of chromosomes; of the two ...
s, horses, camels, pigs, and sometimes, it was said, even from old shoes; a bit of "real stuff" was added to it, to deceive consumers.[
Ejiao is either prepared as dry gelatin or mixed with powdered oyster shell or pollen to form glue balls. It tastes sweet and slightly bitter.][
]Jesuits
The Society of Jesus (; abbreviation: S.J. or SJ), also known as the Jesuit Order or the Jesuits ( ; ), is a religious order (Catholic), religious order of clerics regular of pontifical right for men in the Catholic Church headquartered in Rom ...
noted that while the "real" ''ejiao'' has no disagreeable taste or smell, the fake product could be distinguished by its unpleasant smell and taste, even when it was made from pig skins (which, supposedly, provided the best approximation of the real thing).[
In the 21st century, ejiao manufacturers experience problems with the supply of genuine donkey hides, as fewer people raise these animals these days. The decreasing supply combined with strong demand for ejiao has led to greatly increased prices for donkey hides in China. This trend is also supported by restrictions on importing animal hides from outside the country. Qin Yufeng, the chairman of a major ejiao manufacturer and a member of Shandong's provincial legislature, has advocated for government support for donkey husbandry.
]
Donkey thefts and population declines
In the mid-2010s, donkey prices in many places around the world began to rise sharply with demand for ejiao. Uganda, Tanzania, Botswana, Niger, Burkina Faso, Mali, and Senegal have banned donkey exports to China. In November 2017, PETA
People for the Ethical Treatment of Animals (PETA; ) is an American animal rights nonprofit organization based in Norfolk, Virginia, and led by Ingrid Newkirk, its international president.
Founded in March 1980 by Newkirk and animal right ...
Asia released eyewitness footage showing donkeys subject to poor conditions and treatment in farms. In November 2019, The Donkey Sanctuary
The Donkey Sanctuary is a British charitable organisation devoted to the welfare of donkeys. The charity, which is based near Sidmouth in Devon, England, was founded in 1969. It is one of the largest equine charities in the world with an annua ...
reported that 4.8 million donkey hides were required to satisfy the global demand for ejiao, resulting in steep declines of donkey populations around the world. The demand for donkey hides was linked to the decline of donkey populations in the Northeast of Brazil, which led the Federal Court of Brazil to suspend the slaughter of donkeys for export to China.
According to the U.S. Congressional Research Service
The Congressional Research Service (CRS) is a public policy research institute of the United States Congress. Operating within the Library of Congress, it works primarily and directly for members of Congress and their committees and staff on a ...
(CRS), between 2.3 million and 4.8 million donkeys are slaughtered annually for ejiao production, prompting fears that both legal and illegal donkey hide trade threatens donkey populations. For example, the donkey population in Botswana declined 70% between 2011 and 2021. In September 2021, Representative Don Beyer
Donald Sternoff Beyer Jr. ( ; born June 20, 1950) is an American businessman, diplomat, and politician serving as the U.S. representative for since 2015. A member of the Democratic Party, his district is located in Northern Virginia and includ ...
( D- VA-8) introduced House Resolution 5203, the Ejiao Act, which would prohibit the knowing sale or transport of ejiao (or products containing ejiao) in interstate or foreign commerce citing the decimation of donkey population and the availability of plant-based gelatins. The bill, introduced to the House Energy and Commerce Committee
The Committee on Energy and Commerce is one of the oldest standing committees of the United States House of Representatives. Established in 1795, it has operated continuously—with various name changes and jurisdictional changes—for more tha ...
, was referred to the committee's Subcommittee on Health.
Applications
In China ''ejiao'' is a traditional medicine used for different types of illnesses. An amount of 5 to 10 grams may be dissolved in hot water or wine and mixed with other ingredients in the traditional Chinese ''materia medica'' or taken alone. It is believed that donkey-hide gelatin treats a variety of conditions such as bleeding, dizziness, insomnia and a dry cough,[ despite a lack of evidence. It has however been found to have a ]hematopoietic
Haematopoiesis (; ; also hematopoiesis in American English, sometimes h(a)emopoiesis) is the formation of blood cellular components. All cellular blood components are derived from haematopoietic stem cells. In a healthy adult human, roughly ten ...
effect, increasing the production of blood cells.[
Quite a few manufacturers produce an ''ejiao'' bar called "gu yuan gao" (固元膏) in Shandong province. Gu yuan gao is made up of ''ejiao'', nuts, sesame, Chinese dates and cooking wine.] It can also be used as an edible coating for dates, producing another type of snack.
''Ejiao'' is also used for applying ''di mo
The ''dimo'' () is a special membrane applied to the transverse Chinese flute called '' dizi'' (or ''di''), giving the instrument its characteristic buzzing timbre.
''Dimo'', made from the tissue-thin membrane from the interior of a specific v ...
'', a special paper-like musical reed membrane
A membrane is a selective barrier; it allows some things to pass through but stops others. Such things may be molecules, ions, or other small particles. Membranes can be generally classified into synthetic membranes and biological membranes. Bi ...
, to the '' dizi'', a transverse Chinese flute
Flutes made in China come in a variety of different types:
Transverse flutes:
* Dizi (and its varieties such as the qudi and bangdi; primary transverse flutes, usually made of bamboo and distinctively has a buzzing membrane)
* Koudi (a small c ...
; it dries quickly, holds quite firmly, and is water-soluble, allowing later replacement of ''di mo''.
The basis for the hematopoietic effect of ''ejiao'' has been found to be at least in part a peptide resulting from the partial hydrolysis of collagen
Collagen () is the main structural protein in the extracellular matrix of the connective tissues of many animals. It is the most abundant protein in mammals, making up 25% to 35% of protein content. Amino acids are bound together to form a trip ...
in the hide. The peptide as well as ''ejiao'' is orally active in anemic mice fed through gastric lavage
Gastric lavage, also commonly called stomach pumping or gastric irrigation or gastric suction, is the process of cleaning out the contents of the stomach using a tube. Since its first recorded use in the early 19th century, it has become one of the ...
, according to a 2016 Chinese study. The same study mentions that candidate peptides match the sequence of bovine collagen.
See also
* Animal glue
Animal glue is an adhesive that is created by prolonged boiling of animal connective tissue in a process called Rendering (animal products), rendering. In addition to being used as an adhesive, it is used for coating and sizing, in decorative co ...
/ Hide glue
References
Further reading
*
{{Donkeys
Adhesives
Traditional Chinese medicine
Donkeys
Skin
Dong'e County