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    Home > Food News > Nutrition News > Experts respond to false claims about cooking oil: all kinds of qualified oils can be eaten with confidence

    Experts respond to false claims about cooking oil: all kinds of qualified oils can be eaten with confidence

    • Last Update: 2021-06-29
    • Source: Internet
    • Author: User
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    China Economic Net, Beijing, September 29 (Reporter Han Xiao) In response to consumer misunderstandings and concerns about the production and consumption of edible oil in recent years, a number of authoritative experts in the domestic grain and oil industry have recently made clarifications that meet the standards Edible oil can be eaten with confidence regardless of whether the production process is leaching or pressing; the “vegetable oil extraction solvent” used in the leaching process is analogous to ordinary gasoline, which is alarmist; the blended oil is scientifically blended to make the oil nutrition and The flavor is improved, and it is believed that there is no scientific basis for nutritional deficiency
    .
    On September 26, the 25th Annual Academic Conference of the Oil Branch of the Chinese Cereals and Oils Society was held in Shandong
    .
    At the meeting, several "nutrition experts" made false statements about "oil processing and nutrition", causing panic among some consumers
    .
    Many domestic oil respect the authority of experts, including Rui Yuan, Jin Qingzhe, Wang Xingguo, He Dongping, Liu Yulan, Chen Wenlin, Valley Keren, Liu Yuan Law, Cao million new, Bursting with sea, Zhou Lifeng, including after careful discussion, made the following clarifications:leaching process and There is no difference between thetwo methods of squeezing process.
    China and the world, there are generally two methods for the preparation of edible vegetable oil: the squeezing method and the leaching method
    .
    The squeezing method is a method of squeezing oil from the oil by mechanical squeezing
    .
    It originated from the oil production method of traditional workshops.
    Although the current squeezing method is a large-scale and industrialized operation, the basic principle has not changed
    .
    The leaching method is a method that uses the extraction principle of food engineering and uses internationally recognized and universal food-grade solvents to extract oil from the oil
    .
    This kind of extraction is essentially a physical dissolution process, and no chemical reaction between oil and solvent occurs during the extraction process
    .
    Judging from the development history of the world's edible fats and oils production process, the leaching oil production process is currently the most advanced production process recognized internationally
    .
    In the early twentieth century, the leaching method was first applied and developed in developed countries.
    In developed countries such as Europe and the United States, more than 90% of vegetable oils are now produced by leaching
    .
    For more than half a century, especially since the reform and opening up, China’s oil science and technology workers have introduced, digested, absorbed and re-innovated foreign advanced technologies, so that the leaching method of oil production technology has been widely used in China’s oil production.
    After considerable development, the leaching method of oil production has accounted for more than 80% of the entire oil production capacity, and its equipment and technical level have reached the current international advanced level
    .
    The leaching process uses hydrocarbon solvents with n-hexane as the main component.
    It was once called "No.
    6 solvent oil", but is now revised as "vegetable oil extraction solvent".
    It is a special solvent specially produced by the state for oil processing.
    Ordinary gasoline with a high boiling point is essentially different.
    This extraction solvent must be food-grade, that is, after heavy metal removal treatment, the residual amount of harmful substances such as lead and arsenic is less than 10μg/kg (one hundred millionth).
    Therefore, it is absolutely safe to use qualified solvents for leaching and to remove it to the greatest extent according to national standards during the refining process
    .
    Solvent residue is also a concern of consumers
    .
    No matter it is the oil obtained by the pressing method or the leaching method, it is not edible at the beginning, and they are all called "crude oil"
    .
    According to national standards, "crude oil" must be refined before it can be eaten, because whether it is leaching or squeezing crude oil, it contains a variety of impurities
    .
    For example, leaching crude oil will inevitably contain residual solvents during the leaching process.
    The national standard stipulates that the solvent residue in crude oil should be less than 100 mg/kg (one in ten thousand), which needs to undergo further processing (ie refining).
    At the same time, the impurities will be further reduced to the solvent residue, and only after reaching the national standard can it become edible refined oil
    .
      The processing process from crude oil to refined oil generally involves degumming, deacidification, decolorization, and deodorization
    .
    In other words, squeezing and leaching only solve the problem of crude oil production, and to turn crude oil into refined oil, it must go through a refining process
    .
    It can be seen that the safety of edible oil does not depend on whether the previous preparation is a pressing or leaching process, but is mainly determined by the subsequent refining process.

    .
    Since the boiling point of n-hexane is less than 70°C, it is easy to remove cleanly during the refining process
    .
    In fact, China's national standard stipulates that the solvent residues in high-grade refined oil (primary oil and secondary oil) cannot be detected, that is to say, it is impossible to detect solvent residues in high-grade refined oil using advanced instruments specified in the national standard
    .
      There is no difference between the leaching process and the pressing process
    .
    Which process to choose for oil preparation, the first consideration is the variety and processing characteristics of vegetable oils.
    The two oil preparation processes only have the applicability of raw materials
    .
    The current international practice is: vegetable oils with higher oil content (such as peanuts and rapeseed, etc.
    ) are usually squeezed and then leached to produce oil; vegetable oils with lower oil content (such as soybeans, etc.
    ) are usually used Direct leaching process to make oil
    .
    In order to make full use of oil resources and improve economic efficiency, the oil cakes after squeezing generally have to continue to be leached to make oil
    .
    Compared with the pressing process, the leaching process has the advantages of less residual oil in the meal, high oil yield, low processing cost, good production conditions, and full utilization of oil resources
    .
    In short, whether it is leaching oil or pressing oil, as long as it meets China's edible oil quality standards and hygienic standards, it is high-quality and safe edible oil, and consumers can eat with confidence
    .
      In summary, the "nutrition expert" said that the leaching method is inferior to the squeezing method, and that the "vegetable oil extraction solvent" used in the leaching process is described as "No.
    6 light gasoline" and is analogous to ordinary gasoline.
    There is indeed a suspicion of alarmism
    .
      Using scientific and reasonable refining methods, the content of benzo(a) pyrene in the refined oil is in full compliance with national standards.
      Benzo(a) pyrene is a member of the polycyclic aromatic hydrocarbon family.
    The initial study found that benzo(a) pyrene can cause skin Carcinoma, after in-depth research, it is found that it is carcinogenic to various organs of the human body (such as: lung, liver, stomach, etc.
    )
    .
    At present, China's national standards limit the content of benzo(a)pyrene in edible oil to no more than 10 μg/kg
    .
      The main causes of benzo(a)pyrene pollution in edible oil are: (1) improper drying of the oil (such as drying on the asphalt pavement); (2) smoke pollution of the oil during the drying process; (3) fried seeds There are several factors such as improper operation (such as excessively high temperature causing scorching of some raw materials)
    .
    High-temperature steaming and frying produces the unique flavor and color of vegetable oils, and it is often accompanied by the risk of producing harmful substances.
    Among them, benzo(a)pyrene is the most representative one
    .
    Although long-term high-temperature steaming and frying is beneficial to increase the oil yield and "flavor", if the temperature is not properly controlled, it will also promote the pyrolysis and polymerization of carbohydrates, proteins, lipids and other components in the preform, resulting in benzo (a ) Pyrene
    .
      The "nutrition expert" said, "How can edible oil contain benzopyrene? The oil production process can produce benzopyrene, and the oil production process does not exceed 150°C, so benzo(a)pyrene will not be produced.
    The temperature of leaching oil can reach 150-250°C, which can produce benzo(a)pyrene, and the leaching oil must contain benzo(a)pyrene"
    .
    It is believed that the excessive benzo(a)pyrene in edible oil is caused by the leaching process, which is a misunderstanding that there is no scientific basis for leaching oil
    .
    First of all, in terms of oil production by the pressing process, if the oil is contaminated by benzo(a) pyrene before pressing, or the oil is roasted at high temperature for a long time during the processing, benzo(a) pyrene is produced, the benzene in these oils And (a) pyrene may be carried into the pressed oil.
    If necessary or reasonable refining and removal is not carried out, the benzo(a) pyrene in the pressed product oil will exceed the standard
    .
    Secondly, the leaching solvent itself does not contain benzo(a)pyrene, and the temperature of the leaching oil production process (grease leaching, mixed oil evaporation, steam stripping, etc.
    ) does not exceed 125°C
    .
    Therefore, if the vegetable oil does not contain benzo(a)pyrene, the leaching process will not form new benzo(a)pyrene
    .
    The usual refining conditions will not generate new benzo(a) pyrene, but can effectively remove most of benzo(a) pyrene.
    For example, rational alkali refining can remove more than 80% of benzo(a) pyrene.
    Using the preferred activated carbon as the adsorbent can remove 99% of benzo(a)pyrene, steam distillation deodorization can remove about 40% of benzo(a)pyrene), and finally make the benzo(a)pyrene in the refined leaching product oil (a) The pyrene content is far below the national standard limit
    .
    On the contrary, if the pressed oil is not fully refined, precipitation and filtration alone cannot effectively remove benzo(a)pyrene.
    Therefore, unrefined pressed oil has the risk of exceeding the standard of benzo(a)pyrene.

    .
    This is also one of the reasons why we do not encourage workshop->
    .
      In summary, the leaching process will not cause the benzo(a) pyrene in the oil to exceed the standard.
    The problem of the benzo(a) pyrene in the edible oil is not necessarily related to the leaching oil production process.
    The key is to look at the quality of the oil.
    , Whether the pretreatment conditions of the oil before squeezing or leaching the oil are suitable, whether the oil refining process is perfect, and so on
    .
    The world has more than one hundred years of history of leaching oil production.
    Both the leaching technology and the solvents used in leaching are constantly improving and upgrading.
    The leaching oil production is still an advanced and safe technology in the world, and it is widely used in vegetable oils.
    Preparation
    .
    In addition, even if the content of benzo(a) pyrene in crude oil is relatively high, don’t be afraid.
    As long as scientific and reasonable refining methods are used, it can be effectively removed, so that the content of benzo(a) pyrene in the finished oil is in full compliance with national standards.

    .
      Appropriate processing of fats and oils can completely remove harmful magazines and retain a variety of nutrients.
      As mentioned earlier, whether it is produced by leaching or pressing, it is called "crude oil" before being refined
    .
    China’s national standards for edible oil stipulate that “crude oil” must be refined to remove harmful components (such as benzopyrene, aflatoxin, solvents, pesticide residues, polycyclic aromatic hydrocarbons, etc.
    ) and certain “impurities” (free fatty acids, Gossypol and gum, etc.
    ), can only be eaten after it becomes a qualified finished oil that meets national standards
    .
      Oil refining requires scientific and reasonable control
    .
    If the task of oil refining is only to remove impurities, then as long as the depth of refining is increased, it is easy to achieve this goal
    .
    However, some ingredients in crude oil are good for human health and should be retained as much as possible during the refining process (such as vitamin E, plant sterols, etc.
    )
    .
    Therefore, oil refining is a flexible and complex project.
    The depth of refining should be based on the crude oil quality and refined oil grade requirements, and the flexible combination of processes and equipment should not only remove harmful components to the greatest extent, but also retain as much as possible.
    Various beneficial ingredients
    .
      For a long time, the Chinese Institute of Cereals and Oils has vigorously advocated "appropriate processing" from the perspective of consumer nutrition and health, emphasized the need to preserve the inherent nutrients in grain and oil raw materials to the greatest extent, and prevent "over-processing", and required the processing precision of oils to be defined appropriately Within the scope, and regulated in the form of national standards (or industry standards)
    .
    The "crude oil" obtained by the leaching method can be refined and processed appropriately to achieve the goal of not only removing harmful impurities, but also retaining a variety of nutrients and not forming new harmful substances, so as to ensure the safety and nutrition of the edible oil
    .
      The "nutrition expert" stated that "the pressed oil does not need to be refined, and there are no residues in it.
    The pressed oil is better" and "the extracted oil will have'gasoline' residues and very few nutrients" and so on
    .
    These views lack the basic knowledge of edible oils
    .
    Here, we also want to tell you that, no matter whether it is pressed or leached, the lipids in the oil that are beneficial to human health, such as phospholipids, pigments, vitamin E, and sterols, will be extracted into the crude oil along with the oil
    .
    Conversely, if the quality of the oil is not good, such as rancidity, mildew, pollution, etc.
    , the harmful components produced by these unfavorable factors will also be carried into the crude oil, resulting in poor quality of the crude oil
    .
    Therefore, whether it is leaching crude oil or squeezing crude oil, it must be refined to meet the requirements of national quality standards and hygienic standards
    .
    It can be seen that as long as the quality of the raw materials is guaranteed, the oil production process is reasonable, and the refining process is in place, the nutrition of the leached product oil can be completely guaranteed.
    It is definitely not like the "nutrition expert" said, "There is almost no leaching oil.
    Inferior oil with nutrients and many gasoline residues"
    .
      The edible oil uses antioxidants according to the national standard, so it can be eaten with confidence  As we all know, if the fat is not stored properly, it will be oxidized and deteriorated under the action of light, air, water and temperature, resulting in peculiar smell or scent, and cannot be eaten
    .
    This will adversely affect the quality of edible fats and oils, which in turn will shorten the shelf life of the finished fats and reduce the flavor and quality of the fats and oils
    .
      In order to ensure that the grease is not oxidized during the warranty period, measures such as dark storage at low temperature, nitrogen filling protection, and the addition of state-allowed antioxidants can be adopted
    .
    In view of the need for refrigeration in low-temperature storage, it is difficult to achieve it in the circulation of oil products and in consumers' homes
    .
    Nitrogen filling protection is a good protection measure, but after the package is opened, the nitrogen escapes and it loses its protective effect on the grease
    .
    Therefore, the most commonly used safe and effective way to delay the oxidative deterioration of fats and oils is to add antioxidants that are allowed by the country
    .
    This is also a common practice internationally
    .
      At present, commonly used synthetic and natural antioxidants that meet the requirements of China's food additive use standards (GB 2760-2014) include: dibutyl hydroxytoluene (BHT), butyl hydroxyanisole (BHA), tert-butyl hydroquinone ( TBHQ), propyl gallate (PG), vitamin E (VE), ascorbyl palmitate and other products
    .
    The amount of these antioxidants used in vegetable oils is generally less than 0.
    2 g/kg (that is, less than 0.
    02%)
    .
      For safety and performance considerations, the antioxidant commonly used in edible oils and fats in China today is TBHQ
    .
    As early as 1972, TBHQ has been accepted and recognized by the U.
    S.
    Food and Drug Administration (FDA).
    Its application in laboratories and industrial production has shown excellent protection for vegetable oils.
    The FDA stipulates that TBHQ is in oils.
    The limit of use is 0.
    02% of grease
    .
    The Food Additives Expert Committee of the United Nations and the World Health Organization (FAO/WHO) has conducted many studies on TBHQ.
    It has been shown that TBHQ is used as an antioxidant and will not produce genotoxic effects in the body, and further genotoxicity studies are no longer necessary.

    .
    In addition, some oils also use vitamin E as an antioxidant
    .
    However, BHA and BHT have long been no longer used in the processing of edible vegetable oils in China due to price, use effect and other reasons
    .
      Therefore, the use of antioxidants is not as the "nutrition expert" said, "China's edible oil and fat antioxidants are basically BHA and BHT"
    .
    In addition, the "nutrition expert" said that "BHA and BHT can easily lead to gastric cancer and liver cancer" is even more open to question
    .
    It can be seen that there is no problem with the safety of edible oils that use antioxidants in accordance with national standards, and consumers can rest assured to buy and eat
    .
      There is no scientific basis for  the statement that edible blended oil is "no nutrition".
    The "nutrition expert" stated in the program that "the blended oil is not very good, and it is basically refined".
    This statement completely denies blended oil once again proves that the "nutrition expert" "The lack of scientific understanding of refined oil also shows that he has a great misunderstanding of blended oil
    .
      Blended oil, also known as blended oil, is an edible oil prepared by blending two or more refined oils in a certain proportion according to the needs of nutritional balance or flavor
    .
    Through scientific blending, the nutrition and flavor of edible oil can be improved, and it is more suitable for daily cooking such as frying, frying, frying, frying or cold dressing
    .
    The blended oil generally uses refined soybean oil, rapeseed oil, peanut oil, sunflower oil, cottonseed oil, etc.
    as the main raw material oil, with a certain amount of flavor oil or refined rice oil, corn oil, camellia seed oil, olive oil, safflower seed oil, wheat germ oil and so on specialty oils and fats
    .
    Common sense tells us that both squeezed oil and leached oil need to be refined to save profits, and the degree of refining of each oil is determined by the quality of crude oil and the use of refined oil, and it is not the same
    .
    The refined oil contains a variety of nutrients.
    Therefore, there is no scientific basis for "the blended oil is not good" and "no nutrition"
    .
      Both the "Dietary Guidelines for Chinese Residents (2016)" issued by the National Health and Family Planning Commission in 2016 and the 2015 version of the "American Dietary Guidelines" emphasize the need for diversification of food, which is no exception for edible oils, that is to say, all kinds of edible oils All have to be eaten, and the varieties should be varied
    .
    Generally speaking, the caloric value of various oil products is similar, but the types and contents of nutrients are different
    .
    Blended oil is a scientific formula of two or more oils.
    It not only has a better balance of fatty acid composition than a single vegetable oil, but also contains more abundant and diverse nutrients
    .
    Therefore, in the reasonable combination of nutrients, blended oil has more advantages than single vegetable oil
    .
    Similarly, here is also a response to the fallacy that some people classify blended oil as waste oil
    .
      Of course, while fully affirming the above-mentioned advantages of blended oil, we should also realize that since there is no national standard for edible blended oil in our country, the current edible blended oil market has problems such as confusion, complicated names and shoddy products.
    The phenomenon is that blended oil producers often name blended oils with high-priced oil products with a small proportion
    .
      In order to regulate the market behavior of blended oil products, the country’s forthcoming "Edible Vegetable Oil" national standard has made two important provisions for blended oil: First, blended oil is uniformly referred to as “edible vegetable blended oil” and cannot be used as high-priced oil.
    The second is that the label of the blended oil should indicate the proportion of various vegetable oils, which means that the formula of the blended oil must be announced
    .
    We believe that with the issuance and implementation of national standards, the scientific connotation and nutritional value of blended oil will be truly reflected and will be loved by consumers
    .
      In addition, the "nutrition expert" also has many omissions in some of the discussions about "genetically modified oil", "saturated fatty acid" and "margarine"
    .
    Take "genetically modified oil" as an example.
    Because the genetically modified ingredients in genetically modified oils are based on protein and are not combined with fats, it is difficult to detect genetically modified ingredients in edible oils produced from genetically modified oils
    .
    This shows that the edible oil produced with genetically modified oil is safe, and consumers can eat with confidence.

    .
      All in all, China's oil processing industry and oil market are generally healthy and upward
    .
    The edible oil products on the market are safe as long as they meet the edible oil quality standards and hygiene standards of our country, and consumers can eat them with confidence
    .
    At the same time, consumers are advised to treat the safety issues of edible oil with a scientific perspective to avoid being misled by rumors and falling into unnecessary panic
    .
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