Cooking Oils in the supermarket

The Danger of Most Oils Displayed on Supermarket Shelves

The Hong Kong Consumer Council tested 60 types of cooking oil from various brands and found 46 of them contained glycidol, a substance that constitute a risk for cancer development. It is one of the main contaminants in processed oils that is generated during the deodorisation step of the refining process of edible oil. Although there are no safe levels set for it anywhere in the world, it is best not to have any cancer-causing substances present in the oil you choose to use. Among the brands of cooking oil with the highest measured concentrations of glycidol are Olitalia, Rizi, Knife, DCH and Tripod. Both Olitalia and Knife brands are commonly sold in Singapore. 


In addition to glycidol, the council also found that 41 samples contain phthalates – chemicals that are used to soften PVC plastic. Phthalates may contaminate the oil due to contact with plastic material used during transportation and storage. According to research studies, phthalates can damage the liver, kidneys, lungs, and reproductive system — particularly developing testes. Four of the 41 samples tested positive for phthalates were found to be above European Union safe levels. These 4 brands are Bontaste, Sunny Meadow, Select and DCH. Did you know that Sunny Meadow is made in Singapore?



Furthermore, the council also found that some brands of cooking oil contain 3-monochloropropane (3-MCPD), which is developed in vegetable oils during the refining process. High amounts of 3-MCPD may cause damage to kidney and testis. 


Since most contaminants are derived from the refining process, cold-pressed oils which are stored in glass bottles would be a far safer and healthier choice. Nonetheless, most of the cold-pressed oils have low smoke points and cannot withstand high-heat cooking. Camelina oil or camellia oils are two oils which can kill two birds with one stone – they are cold-pressed and have high smoke points.  

Not all cold-pressed oils are created equal. Although cold pressing does not involve the use of chemicals in the production process, some crops may be contaminated with insecticides, herbicides, metals or industrial wastes. Hence, it is crucial to go for oils that are cold-pressed from crops organically-grown in pristine and contamination-free regions. The surest way is to purchase oils from trustworthy and credible manufacturers or suppliers.