Soy sauce is a staple condiment in many households, adding a savory umami flavor to dishes. However, recent studies have shown that some soy sauce brands may contain a harmful chemical called 3-MCPD.
This chemical is a byproduct of the production process and has been linked to potential health risks. In this article, we will explore which brands of soy sauce have been found to contain 3-MCPD and what steps are being taken to reduce its presence in our food.
So, if you’re a soy sauce lover, keep reading to learn more about this concerning issue.
What Brands Of Soy Sauce Contain 3-Mcpd?
According to various studies, several brands of soy sauce have been found to contain 3-MCPD. These brands include Amoy, Pearl River Bridge, Silver Swan, Lee Kum Kee, and Kim Ye Yong. The levels of 3-MCPD in these brands varied, with some exceeding the maximum limit established by certain countries’ food safety authorities.
It’s important to note that not all soy sauce brands contain 3-MCPD. Some brands, such as Kikkoman, use a natural brewing method that does not trigger any 3-MCPD chemical reaction. These products are manufactured in Europe according to HACCP and are in conformity with EU Directives.
What Is 3-MCPD And Why Is It Harmful?
3-MCPD, or 3-monochloropropane-1,2-diol, is an organic chemical compound that is commonly found in food products. It is a byproduct of the process used to speed up protein hydrolysis in foods treated at high temperatures with hydrochloric acid. It can also occur in foods that have been in contact with materials containing epichlorohydrin-based wet-strength resins, which are used in the production of some tea bags and sausage casings.
The compound has attracted attention as a chemical food contaminant and is suspected to be carcinogenic in humans. Animal studies have shown that long-term exposure to high levels of 3-MCPD can cause adverse effects on the kidneys, central nervous system, and male reproductive system. The International Agency for Research on Cancer has classified 3-MCPD as a group 2B agent, meaning it is possibly carcinogenic to humans.
The production of 3-MCPD involves the reaction between chloride and the glycerol backbone of lipids. This reaction can occur during the hydrolysis process used to produce acid-hydrolyzed vegetable proteins (acid-HVPs) that are commonly used as flavor enhancers and ingredients in condiments such as soy sauce, oyster sauce, and chicken powder. The use of hydrochloric acid during this process can accelerate the reaction and increase the levels of 3-MCPD in the final product.
To reduce the formation of 3-MCPD in condiments, manufacturers are advised to observe good manufacturing practices and follow the “Code of Practice for the Reduction of 3-Monochloropropane-1,2-diol (3-MCPD) during the Production of Acid-HVPs and Products that Contain Acid-HVPs” published by the Codex Alimentarius Commission. Approaches to reduce the level of 3-MCPD in acid-HVPs include controlling the temperature and heating time during acid hydrolysis, using a secondary alkaline hydrolysis to remove any 3-MCPD formed during acid hydrolysis, and using sulfuric acid instead of hydrochloric acid during acid hydrolysis.
Consumers should be aware of the potential health risks associated with consuming products that contain high levels of 3-MCPD. It is important to check product labels and choose brands that use natural fermentation methods or have been tested for low levels of 3-MCPD.
How Is 3-MCPD Formed In Soy Sauce Production?
3-MCPD is a naturally occurring contaminant that can be formed during the production of soy sauce. Soy sauce is made from vegetable protein of soybeans that is fermented or acid-hydrolyzed into small particles of amino acids, aldehydes, ketones and organic acids. During the production of acid-hydrolyzed protein, hydrochloric acid is added to facilitate hydrolysis of vegetable protein, which saves time taken for its hydrolysis by microbial enzymes. However, during this process, the reaction of hydrochloric acid with the residual fats and oils in vegetable protein over heating may form 3-MCPD.
The prolonged heating in high temperature is believed to be responsible for the formation of 3-MCPD in the production of acid-HVP soy sauce, likely due to the presence of glycerol, lecithin, and other glycerides in the soy sauce itself. This means that soy sauces produced by rapid fermentation or mixed method are more likely to contain 3-MCPD compared to those produced by traditional fermentation method.
It’s important to note that 3-MCPD is a contaminant that is formed during food manufacturing, cooking and other processing activities. According to the report of the Joint FAO/WHO Expert Committee on Food Additives (JECFA) of the United Nations in 2001, it concluded that 3-MCPD is not carcinogenic to humans and not genotoxic in vivo in experimental animals. However, JECFA recommends the maximum tolerable daily intake of 3-MCPD to be 2mg/kg body weight.
To ensure safety when consuming soy sauce, it’s recommended to purchase soy sauce from reputable shops with good hygiene conditions, carefully read about the label on the packaging and the specified expiry date, check whether packaging of soy sauce is intact and without damage, keep soy sauce in a cool and well-ventilated place or under cold storage, and avoid buying or consuming any soy sauce if doubtful about its safety on health.
What Are The Health Risks Associated With 3-MCPD?
Research studies have shown that 3-MCPD is possibly carcinogenic and can cause cancer. In rodents, 3-MCPD primarily affects the kidney and the testes, which can lead to kidney damage and reduced male fertility. Additionally, higher consumption of 3-MCPD over time has been linked to increased health risks. The International Agency for Research on Cancer classifies 3-MCPD as a possible human carcinogen, while glycidol, a breakdown product of 3-MCPDE and GE, is classified as a probable human carcinogen.
The European Food Safety Authority (EFSA) has set a tolerable daily intake (TDI) of 2 μg/kg body weight per day for 3-MCPD and its fatty acid esters. This level is considered safe for most consumers, but there is a potential health concern among high consumers in younger age groups. In the worst-case scenario, infants receiving formula only may slightly exceed the safe level.
In laboratory studies, 3-MCPDE and GE break down in the digestive tract to 3-MCPD and glycidol. While glycidol is a known carcinogen in rodents, no genotoxic potential has been demonstrated for free 3-MCPD. However, JECFA notes that the esters are substantially hydrolysed to 3-MCPD in the gastrointestinal tract, delivering the same toxicity as free 3-MCPD.
It’s important to note that while the levels of 3-MCPD found in soy sauce may vary by brand, consuming excessive amounts of any food product containing this contaminant could pose health risks. As such, it’s recommended to consume soy sauce in moderation and choose brands that follow safe manufacturing practices.
What Steps Are Being Taken To Reduce 3-MCPD In Soy Sauce?
To reduce the formation of 3-MCPD in soy sauce, manufacturers are advised to observe good manufacturing practices and reduce the level of 3-MCPD in condiments as low as reasonably achievable. The Codex has published the “Code of Practice for the Reduction of 3-Monochloropropane-1,2-diol (3-MCPD) during the Production of Acid-HVPs and Products that Contain Acid-HVPs,” which provides guidelines for manufacturers to follow.
One approach to reducing the level of 3-MCPD in soy sauce is to use sulphuric acid instead of hydrochloric acid during acid hydrolysis in the manufacture of acid-HVPs. This can significantly reduce the formation of 3-MCPD.
Another approach is to accurately add hydrochloric acid during the hydrolysis process. Excess amounts of hydrochloric acid are a key reason for 3-MCPD production. A detailed study of the amount of acid required to hydrolyze available protein can prevent the formation of 3-MCPD.
Manufacturers can also use a continuous dosing mechanism for adding acid rather than adding it all at once at the beginning. The added hydrochloric acid is not consumed immediately by protein, and some amount is never consumed, which needs to be neutralized at the end. This excess amount can be used by glycerol to produce 3-MCPD, so a dosing mechanism can help reduce the excess of acid.
Lastly, using high pressure and lower temperature during production can significantly reduce the formation of 3-MCPD. 3-MCPD is produced significantly at temperatures above 55 degrees Celsius, which is a significant contributor to its formation. Using high pressure, an equivalent amount of hydrolysis can be achieved at 55 degrees Celsius, which can reduce 3-MCPD significantly.
Tips For Choosing Safe Soy Sauce Brands.
If you want to ensure that the soy sauce you purchase is safe to consume, here are some tips to keep in mind:
1. Purchase soy sauce from reputable shops that maintain good hygiene conditions. This will help to reduce the risk of contamination during production and storage.
2. Carefully read the label on the packaging and check the specified expiry date. This will help you to determine whether the product is fresh and safe for consumption.
3. Check whether the packaging of the soy sauce is intact and without damage. Damaged packaging can be a sign of contamination or improper storage.
4. Store your soy sauce in a cool and well-ventilated place or under cold storage. This will help to maintain its quality and freshness.
5. If the soy sauce has an abnormal taste or repulsive smell, do not buy or consume it. These can be signs of spoilage or contamination.
6. Be a smart consumer and do not buy or consume any soy sauce if you are doubtful about its safety on health.
By following these tips, you can reduce your risk of exposure to 3-MCPD and other harmful contaminants that may be present in some soy sauce brands.