
Gutter oil, trench oil, sewer oil, hogwash oil and tainted oil (, or ) are Chinese slang terms primarily used in
China
China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
and
Taiwan
Taiwan, officially the Republic of China (ROC), is a country in East Asia. The main geography of Taiwan, island of Taiwan, also known as ''Formosa'', lies between the East China Sea, East and South China Seas in the northwestern Pacific Ocea ...
to refer to
recycled oil.
It can be used to describe the illicit practice of restaurants reusing
cooking oil
Cooking oil (also known as edible oil) is a plant or animal liquid fat used in frying, baking, and other types of cooking. Oil allows higher cooking temperatures than water, making cooking faster and more flavorful, while likewise distributing h ...
that has already been cooked for longer than safety codes permit. It can also be used to describe the reprocessing of
yellow grease collected from sources such as restaurant
fryers,
kitchen
A kitchen is a room (architecture), room or part of a room used for cooking and food preparation in a dwelling or in a commercial establishment. A modern middle-class residential kitchen is typically equipped with a Kitchen stove, stove, a sink ...
,
slaughterhouse waste and sewer drains.
[Alexa Olese]
"Gutter Oil: China Sounds Alarm Over Filthy Cooking Oil"
. 20 July 2010[Max Fishe]
"You may never eat street food in China again after watching this video"
. 28 October 2013
Since 2011, the Chinese government has significantly cracked down on the reuse of gutter oil for human consumption,
with the Chinese government also implementing clearer regulations for dealing with waste oil.
Selling gutter oil in China can result in lengthy prison sentences or the
death sentence with reprieve
Death sentence with reprieve (, abbr: ) is a criminal punishment found in chapter 5 (death penalty), sections 48, 50 and 51 of the criminal law of the People's Republic of China. It is a two-year suspended sentence where the execution is only ca ...
. For example, in 2014, businessman
Zhu Chuanfeng was sentenced to the latter for selling gutter oil.
That same year, a major gutter oil scandal was uncovered in Taiwan. In 2015, Yeh Wen-hsiang, who was the chairman of a Taiwanese food company, was sentenced to 22 years imprisonment and fined the equivalent of $1.6 million for selling 243 tonnes of gutter oil.
History
The first documented case of gutter oil in Taiwan was reported in 1985. In a subsequent investigation, 22 people were arrested for involvement in a recycling oil ring over 10 years based in Taipei. The worst offender was sentenced to 7 years in prison.
The first documented case of gutter oil in mainland China was reported in 2000, when a
street vendor
A hawker is a vendor of merchandise that can be easily transported; the term is roughly synonymous with costermonger or peddler. In most places where the term is used, a hawker sells inexpensive goods, handicrafts, or food items. Whether stationa ...
was found to be selling oil obtained from restaurant
garbage disposals
A garbage disposal unit (also known as a waste disposal unit, food waste disposer (FWD), in-sink macerator, garbage disposer, or garburator) is a device, usually electrically powered, installed under a kitchen sink between the sink's drain a ...
.
[He Jiangyong and Liu Ziqian]
"Sick Slick"
, ''NewsChina Magazine'', December 2011.
Some street
vendors and
restaurants in
China
China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
are reported to have illegally used
recycled oil unfit for human consumption to cook food.
[Tian Peng, Sun Licha]
"Cooking Oil's Final Destination"
''The Economic Observer'' 14 November 2011[Mark Astle]
Chinese officials arrest more than 100 in rotten meat-based 'gutter oil' crackdown
''Food Quality News'', 5 April 2012
''China Daily'', 24 May 2012.
In 2010, it was estimated that gutter oil represented 10% of China's edible oil market (with 1 in every 10 restaurants using it) and that 3 million tonnes of gutter oil were consumed in China annually,
/nowiki>] Guanghua Daily March 19, 2010 with a network of distributors of gutter oil across central and eastern China.
In 2011, the Chinese government began a major crackdown on the re-use of gutter oil for human consumption.
In 2011, they had arrested 32 people for producing the oil and had seized 90 tonnes of it in 14 provinces. This amount is equivalent to that of around one-tenth of oil typically used by restaurants. As Feng Ping of the China Meat Research Center has said: "The illegal oil shows no difference in appearance and indicators after refining and purification, because the law breakers are skillful at coping with the established standards."
In September 2012, an ongoing investigation into the suspected use of gutter oil as a raw material in the
Chinese pharmaceutical industry was revealed.
A scandal involving 240 tons of gutter oil in Taiwan affecting hundreds of companies and thousands of eateries, some of which may have been exported overseas, broke in September 2014.
In 2018, researchers worked on identifying different components in gutter oil using 1H NMR (
proton nuclear magnetic resonance), MALDI-MS (
matrix-assisted laser desorption/ionization-mass spectrometry) and HPLC (
high-performance liquid chromatography
High-performance liquid chromatography (HPLC), formerly referred to as high-pressure liquid chromatography, is a technique in analytical chemistry used to separate, identify, and quantify specific components in mixtures. The mixtures can origin ...
).
Regulations and law enforcement
Chinese law states that industrial-grade animal fat is not allowed for use in food products because it does not meet basic hygiene standards and may contain high levels of potentially toxic contaminants. The national and local governments are researching ways to test and identify gutter oil but there were no nationwide standards in place to help with this process. The government is looking into methods that rely on technical equipment as well as on-site instant tests to screen suspect oil. There are five proposed tests for gutter oil but each has failed to accurately detect it.
Due to China's vast industry of factories involved with legal waste oil processing to create products like plastics, rubbers, fuels, soaps, etc., there have been abundant rumors and allegations about unscrupulous middlemen selling gutter oil for cooking and frying.
However, it remains difficult to prove and prosecute such profiteers.
Food safety articles funded by
PRC provincial science grants attribute continued difficulties in regulatory enforcement to the decentralized nature of the logistics chain, inadequate national infrastructure for disposal/recycling, and frequent innovations in visually and chemically disguising gutter oil.
In August and September 2011, the Beijing city government passed two new sets of regulations. The first was "On Accelerating the City's Food Waste and Waste Oil Recycling Program". Its goals are to increase daily
food waste
The causes of food going uneaten are numerous and occur throughout the food system, during food production, production, food processing, processing, Food distribution, distribution, Grocery store, retail and food service sales, and Social clas ...
processing to 2,200 tons by 2012 and to 2,900 tons by 2015. Additionally, the intent of the regulations is to create a system that "should be a unified, standardized, and orderly processing of waste oil collection and improvement of the transportation system".
[Tian Peng, Sun Licha]
"Cooking Oil's Final Destination"
''The Economic Observer'' 14 November 2011 The second set of regulations by the city of Beijing, called the "Beijing Municipal Solid Waste Regulations", was passed in September 2011. The regulations specifically target the two sources of gutter oil: food waste and used oil. The central government intends for these two sets of regulations to serve as national examples, yet wants every municipality nationally to find their own solutions to the food waste and gutter oil problem.
''China Daily'', 24 May 2012.
A nationwide campaign was set in motion in August 2011 to crack down on the widespread production and selling of gutter oil. The law enforcement campaign uncovered 100 gutter oil manufacturers and arrested more than 800 people allegedly involved in the production and sale of gutter oil. In April 2012, another crackdown occurred with an additional 100 arrests made and 13 illegal workshops closed down across four provinces.
[Mark Astle]
Chinese officials arrest more than 100 in rotten meat-based 'gutter oil' crackdown
''Food Quality News'', 5 April 2012 According to a notice released jointly by the
Supreme People's Court
The Supreme People's Court of the People's Republic of China (SPC) is the highest court of the People's Republic of China. It hears appeals of cases from the high people's courts and is the trial court for cases about matters of national ...
, the
Supreme People's Procuratorate and the
Ministry of Public Security
Ministry of Public Security can refer to:
* Ministry of Justice and Public Security (Brazil)
* Ministry of Public Security of Burundi
* Ministry of Public Security (Chile)
* Ministry of Public Security (China)
* Ministry of Public Security of Co ...
, the
death penalty
Capital punishment, also known as the death penalty and formerly called judicial homicide, is the state-sanctioned killing of a person as punishment for actual or supposed misconduct. The sentence ordering that an offender be punished in s ...
will now be an option when prosecuting more serious cases of gutter oil manufacturing in the country. More severe punishments will also be given out to government and public officials who fail to properly address matters related to gutter oil. The State Council said inspectors would target edible oil trade fairs and wholesale markets and called for inspections of oil being used at restaurants, school cafeterias, work canteens and kitchens at construction sites. The State Council also stated that businesses that use recycled oil would be forced to close temporarily or lose their business license while peddlers who sell the oil could be criminally prosecuted.
[ In October 2013, a man from eastern China's Jiangsu Province was sentenced to life imprisonment for profiting heavily from making and selling gutter oil.]
In January 2014, Zhu Chuanfeng was sentenced to death with a two-year reprieve, and his brothers Zhu Chuanqing and Zhu Chuanbo were sentenced to life in prison for selling gutter oil.
Production and distribution
Entire illicit supply chains dedicated to collecting, processing, and reselling gutter oil have been discovered by regulators in China. Multiple low-end restaurants in China have been found to cook with gutter oil. Additionally, in 2012, the Chinese government accused a Chinese pharmaceutical company of using gutter oil as a precursor for the manufacturing of cephalosporin
The cephalosporins (sg. ) are a class of β-lactam antibiotics originally derived from the fungus '' Acremonium'', which was previously known as ''Cephalosporium''.
Together with cephamycins, they constitute a subgroup of β-lactam antibio ...
antibiotics. About two to three million tons of cooking oil containing cancerous substances are produced in China each year. In 2010 it was estimated that approximately one tenth of the meals consumed by people in China could contain gutter oil.
Collected waste oil is sold to local workshops or small factories for cleaning and packaging. When sold to workshops it is often transported by bicycle mounted collectors; afterwards, the oil is held in 200-liter barrels at the workshops until it is processed.[Alexa Olese]
"Gutter Oil: China Sounds Alarm Over Filthy Cooking Oil"
''Huffington Post'', 20 July 2010 On other occasions the oil goes to industrial cooking oil refineries for further processing before it finally reaches its end purpose.
Reprocessing of used cooking oil is often very rudimentary; techniques include filtration
Filtration is a physical separation process that separates solid matter and fluid from a mixture using a ''filter medium'' that has a complex structure through which only the fluid can pass. Solid particles that cannot pass through the filte ...
, boiling, refining, and the removal of some adulterants. It is then packaged and resold as a cheaper alternative to normal cooking oil.
Another version of gutter oil uses discarded animal parts, animal fat and skins, internal organs, and expired or otherwise low-quality meat, which is then cooked in large vats to extract the oil.
Some lower-market restaurants have long-term purchase agreements with oil recyclers for selling their used oil.[David Barboz]
Recycled Cooking Oil Found to Be Latest Hazard in China
''The New York Times'', 31 March 2010 Low-end restaurants and street vendors are the biggest end users of gutter oil, as they operate with lower profit margins than bigger restaurants. Oil is a large kitchen supply cost for some restaurants, so obtaining cheaper oil can allow a marginal restaurant to reduce its overall expenses. Chinese food is generally heavily dependent on oil due to most foods being fried, so cheaper meal prices for many price-sensitive consumers are possible if gutter oil is used instead of virgin oil.[Xinhua News Agency]
14 September 2011. The situation becomes more serious because it is hard to distinguish reprocessed gutter oil from legitimate oil. Bleach
Bleach is the generic name for any chemical product that is used industrially or domestically to remove color from (i.e. to whiten) fabric or fiber (in a process called bleaching) or to disinfect after cleaning. It often refers specifically t ...
is used to transform gutter oil's dark color into a more natural-looking one, and alkali
In chemistry, an alkali (; from the Arabic word , ) is a basic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a soluble base has a pH greater than 7.0. The a ...
additives are used to neutralize the abnormal pH caused by high concentrations of animal fats
Animal fats are lipids derived from animals which are used by the animal for a multitude of functions, or can be used by humans for dietary, sanitary, and cosmetic purposes. Depending on the temperature of the fat, it can change between a solid s ...
.[
Used kitchen oil can be purchased for between $859 and $937 per ton, while the cleaned and refined product can sell for $1,560 per ton.][Li L]
In the Tank, Not on the Table
''The Beijing Review'' 17 November 2011 Thus there is great economic incentive to produce and sell gutter oil.
Health effects
Gutter oil has been shown to be toxic, causing diarrhea
Diarrhea (American English), also spelled diarrhoea or diarrhœa (British English), is the condition of having at least three loose, liquid, or watery bowel movements in a day. It often lasts for a few days and can result in dehydration d ...
and abdominal pain. Long-term consumption of gutter oil may cause many foodborne illnesses because the oil may contain excessive amounts of cholesterol
Cholesterol is the principal sterol of all higher animals, distributed in body Tissue (biology), tissues, especially the brain and spinal cord, and in Animal fat, animal fats and oils.
Cholesterol is biosynthesis, biosynthesized by all anima ...
, trans-fats, toxic heavy metals
upright=1.2, Crystals of lead.html" ;"title="osmium, a heavy metal nearly twice as dense as lead">osmium, a heavy metal nearly twice as dense as lead
Heavy metals is a controversial and ambiguous term for metallic elements with relatively h ...
and pathogen
In biology, a pathogen (, "suffering", "passion" and , "producer of"), in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a Germ theory of d ...
s such as 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 ...
, but also carcinogenic substances such as polycyclic aromatic hydrocarbons and aflatoxins, and therefore lead to stomach and liver cancer.[Austin Ramzy]
China Cracks Down on "Gutter Oil," a Substance Even Worse Than its Name
''Time'', 13 September 2011. Zeng Jing of the Guangdong Armed Police Hospital said of gutter oil: "Animal and vegetable fat in refined waste oil will undergo rancidity, oxidation and decomposition after contamination. It will cause indigestion, insomnia
Insomnia, also known as sleeplessness, is a sleep disorder where people have difficulty sleeping. They may have difficulty falling asleep, or staying asleep for as long as desired. Insomnia is typically followed by daytime sleepiness, low ene ...
, liver discomfort and other symptoms."
Due to rumours and the fear of Chinese customers of restaurants using gutter oil in their cooking, it has been reported that some people in China have resorted to bringing their own cooking oil with them from home into restaurants and instructing chefs to use their home-brought oil in their kitchen when preparing their food instead of the restaurant's own cooking oil.
Legal disposal and reuse of waste oil
Legitimate producers of gutter oil sell the processed oil for use in the chemical or energy industries. However, such refiners can also have illegal side business, as the prices attained by selling it as cooking oil are much higher than if it is sold to the chemical or energy industries such as KBR Energy.
Yellow
Yellow is the color between green and orange on the spectrum of light. It is evoked by light with a dominant wavelength of roughly 575585 nm. It is a primary color in subtractive color systems, used in painting or color printing. In t ...
and brown grease typical of gutter oil are acceptable raw feedstocks for products not intended for human consumption, such as plastics, rubber, rooftops, soap, cosmetics, and bio-fuel.
In the city of Shanghai, it was reported that over 2,000 buses ran on biodiesel that was made from gutter oil, and many gas stations in Shanghai offered gasoline that was produced in part from gutter oil. Sustainable utilization of gutter oil for biofuel production is being explored using different chemical and enzymatic methods.
Gutter oil in other countries
Gutter oil has also been used outside of China as well, albeit not for human consumption. For example, in England
England is a Countries of the United Kingdom, country that is part of the United Kingdom. It is located on the island of Great Britain, of which it covers about 62%, and List of islands of England, more than 100 smaller adjacent islands. It ...
, fatbergs that were dug out of sewers in cities like London
London is the Capital city, capital and List of urban areas in the United Kingdom, largest city of both England and the United Kingdom, with a population of in . London metropolitan area, Its wider metropolitan area is the largest in Wester ...
and Liverpool
Liverpool is a port City status in the United Kingdom, city and metropolitan borough in Merseyside, England. It is situated on the eastern side of the River Mersey, Mersey Estuary, near the Irish Sea, north-west of London. With a population ...
were later reported to be processed to produce biofuel.
See also
* Food safety incidents in China
* Food safety incidents in Taiwan
References
{{Reflist
Health in China
Health in Taiwan
Restaurant food safety scandals
Recycling
Cooking oils
2014 health disasters
2014 in China
2014 in Taiwan
Adulteration
Economic history of China
Scandals in China
Scandals in Taiwan
Food fraud