Oncom ( IPA: ) is a fermented food which is one of the traditional staples of the Sundanese

cuisine A cuisine is a style of cooking characterized by distinctive ingredients, List of cooking techniques, techniques and Dish (food), dishes, and usually associated with a specific culture or geographic region. Regional food preparation techniques, ...

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...

. There are two kinds of oncom: red oncom and black oncom. The food is closely related to tempeh; both are fermented using

mold A mold () or mould () is one of the structures that certain fungus, fungi can form. The dust-like, colored appearance of molds is due to the formation of Spore#Fungi, spores containing Secondary metabolite#Fungal secondary metabolites, fungal ...

. Usually, oncom is made from the

by-product A by-product or byproduct is a secondary product derived from a production process, manufacturing process or chemical reaction; it is not the primary product or service being produced. A by-product can be useful and marketable or it can be cons ...

s from the production of other foods: soy pulp remains from making

tofu or bean curd is a food prepared by Coagulation (milk), coagulating soy milk and then pressing the resulting curds into solid white blocks of varying softness: ''silken'', ''soft'', ''firm'', and ''extra (or super) firm''. It originated in Chin ...

peanut The peanut (''Arachis hypogaea''), also known as the groundnut, goober (US), goober pea, pindar (US) or monkey nut (UK), is a legume crop grown mainly for its edible seeds. It is widely grown in the tropics and subtropics by small and large ...

press cake remains after the oil has been pressed out,

cassava ''Manihot esculenta'', common name, commonly called cassava, manioc, or yuca (among numerous regional names), is a woody shrub of the spurge family, Euphorbiaceae, native to South America, from Brazil, Paraguay and parts of the Andes. Although ...

tailings when extracting the

starch Starch or amylum is a polymeric carbohydrate consisting of numerous glucose units joined by glycosidic bonds. This polysaccharide is produced by most green plants for energy storage. Worldwide, it is the most common carbohydrate in human diet ...

( ''aci sampeu''),

coconut The coconut tree (''Cocos nucifera'') is a member of the palm tree family (biology), family (Arecaceae) and the only living species of the genus ''Cocos''. The term "coconut" (or the archaic "cocoanut") can refer to the whole coconut palm, ...

press cake remaining after the oil has been pressed out or when coconut milk has been produced. Since oncom production uses

s to make food, it increases the economic efficiency of food production. Black oncom is made by using '' Rhizopus oligosporus'' while red oncom is made by using '' Neurospora intermedia'' var. ''oncomensis''. It is the only traditional human food produced from '' Neurospora''. Red oncom has been found to reduce the cholesterol levels of rats.

Toxicity

In the production of oncom, sanitation and hygiene are important to avoid contaminating the culture with

bacteria Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micr ...

or other

fungi A fungus (: fungi , , , or ; or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified as one ...

like '' Aspergillus flavus'' (which produces aflatoxin). '' Neurospora intermedia var. oncomensis'' and '' Rhizopus oligosporus'' reduce the aflatoxin produced by '' Aspergillus flavus''. However, aflatoxin-producing molds (''Aspergillus'' spp.) are often naturally present on peanut press cake. Furthermore, coconut press cake can harbor the very dangerous '' Burkholderia gladioli'', which produces two highly toxic compounds – bongkrek acid and toxoflavin. William Shurtleff and Akiko Aoyagi address toxicity in thei
book section on oncom
While it is known that

soybean The soybean, soy bean, or soya bean (''Glycine max'') is a species of legume native to East Asia, widely grown for its edible bean. Soy is a staple crop, the world's most grown legume, and an important animal feed. Soy is a key source o ...

s are the best substrate for growing ''R. oligosporus'' to produce tempeh, oncom has not been as thoroughly studied; the best fermentation substrates for producing oncom are not yet known.

Cooking methods

Oncom can be prepared and cooked in various ways. It can be simply deep fried as '' gorengan'' fritters, seasoned and cooked in a banana leaf pouch as pepes, or roasted, seasoned, and mixed with steamed rice as '' nasi tutug oncom''. Oncom is also a selected filling for ''comro'', ''

lontong ''Lontong'' () is an Indonesian cuisine, Indonesian dish made of compressed rice cake in the form of a Cylinder (geometry), cylinder wrapped inside a banana leaf, commonly found in Indonesia, Malaysia, and Singapore. Rice is rolled inside a bana ...

'' and ''

arem-arem Arem-arem is an Indonesian- Javanese compressed rice cake in the form of a cylinder wrapped inside a banana leaf, filled with diced vegetables, '' tempeh,'' or '' oncom'', and eaten as a snack. It is sometimes also filled with minced meat or ...

'' rice dumplings. ''Comro'' in particular is a popular Sundanese snack, the name was an abbreviation of ''oncom di jero'' which means "oncom inside".

Gallery

File:Oncom tekstur.jpg, Closer view of red oncom mold Image:Pepes Oncom.jpg, Oncom cooked as pepes dish. Image:Makanan Khas Sunda.jpg, Nasi tutug oncom, roasted oncom mashed with steamed rice, served with side dishes.

Toxicity

Cooking methods

Gallery

See also

References

Further reading