The gizzard, also referred to as the ventriculus, gastric mill, and gigerium, is an organ in the digestive tract found in birds, reptiles, earthworms, some fish, and other creatures. This specialized stomach constructed of thick, muscular walls is used for grinding up food. In certain insects and molluscs, the gizzard features chitinous plates or teeth.
Etymology
The word "gizzard" comes from the
Middle English giserdd, which derives from a similar word in
Old French, and earlier from the
Vulgar Latin "*gicerium", which follows from the
Latin word "gigeria", meaning cooked entrails of poultry. The Latin word "gigeria" is probably derived from the
Persian word for liver, which is "jiger".
Structure
Birds swallow food and store it in their
crop if necessary. Then the food passes into their glandular
stomach, also called the proventriculus, which is also sometimes referred to as the true stomach. This is the secretory part of the stomach. Then the food passes into the ventriculus (also known as the
muscular stomach or
gizzard). The gizzard can grind the food with stones that have been swallowed and pass it back to the true stomach and vice versa. Bird gizzards are lined with a tough layer made of the protein
keratin, to protect the muscles in the gizzard.
Gizzard stones
Some animals that lack teeth will swallow stones or grit to aid in digestion. All birds have gizzards, but not all will swallow stones or grit. The birds that do, employ the following method of '
mastication':
- "A bird swallows small bits of gravel that act as 'teeth' in the gizzard, breaking down hard food such as seeds and thus helping digestion." (Solomon et. al, 2002).
These stones are called
gizzard stones or
gastroliths and are usually smooth and round from the polishing action in the animal's stomach. When too smooth to do their required work, they may be passed or regurgitated.
Animals with gizzards
Emus,
turkeys and
chickens, like all birds, have gizzards.
Mullets (
Mugilidae) found in estuarine waters worldwide, and the gizzard
shad, or mud shad, found in freshwater lakes and streams from New York to Mexico, have gizzards.
The
Gillaroo (
Salmo stomachius), has a gizzard. It is a species of
trout found in
Lough Melvin in
County Fermanagh,
Northern Ireland. It is a distinct species, characterized by a rich coloration. Its gizzard is used to aid the digestion of water
snails, the main item of its diet.
Crocodiles also have gizzards.
Dinosaurs with gizzards
Dinosaurs believed to have had gizzards based on the discovery of gizzard stones recovered near fossils:
Eating gizzards
The gizzards of poultry are a popular food throughout the world. Grilled chicken gizzards are sold as street food in South Korea, China, Taiwan, Japan, Philippines, Haiti, and throughout Southeast Asia. In Indonesia, gizzard and liver are considered as part of a complete fried poultry dish. Chicken gizzards are popular food item in Potterville, Michigan, where a Gizzard Festival is held every year in June. Stewed gizzards are eaten as a snack in Portugal, while pickled turkey gizzards are a traditional food in some parts of the Midwestern United States. In Hungary it is made with paprika. In the Southern United States, the gizzard is typically served fried, sometimes eaten with hot or honey mustard, or added to crawfish boil along with crawfish sauce, and it is also used in traditional New Orleans gumbo. In Chicago, gizzard is battered, deep fried and served with fries and sauce. Gizzard and mashed potato is a popular food in many European countries. In France, especially the Dordogne region, gizzards are eaten in the traditional Perigordian Salad, along with walnuts, croutons and lettuce.
In Yiddish, gizzards are referred to as "pipik'lach", literally meaning navels. The gizzards of kosher species of birds have a green or yellowish membrane lining the inside, which must be peeled off before cooking, as it lends a very bitter taste to the food. In traditional Eastern European Jewish cuisine, the gizzards, necks, and feet of chickens were often cooked together, although not the liver, which per Kosher law must be broiled.
In Uganda, Cameroon and Nigeria, the gizzard of a cooked chicken is traditionally set aside for the oldest or most respected male at the table.
Giblets consist of the heart, liver and gizzard of a bird, and are often eaten themselves or used as the basis for a soup or stock.
Generic meaning
Gizzards can also refer to the general guts, innards or entrails of other animals, as in the phrase 'hand over the treasure or I'll slit yer gizzards me hearty' that may be uttered by a storybook
pirate.
References
- Solomon, E.P., Berg L.P., and Martin D.W., 2002. Biology Sixth Edition. Thomson Learning Inc., Australia, Canada, Mexico, Singapore, Spain, United Kingdom, United States pp. 664
- Dyce, Sack, Wensing, 2002. Textbook of Veterinary Anatomy Third Edition, Saunders. ISBN 0-7216-8966-3