In May, news of maleic acid contamination in the tapioca pearls used in bubble tea (also called boba tea or 珍珠奶茶) spread to Malaysia. Several bubble tea chains published statements through press releases and Facebook stating that their products are free of the substance.
However, in response the Malaysian Healthy Ministry banned eleven Taiwanese food products suspected of containing the chemical substance. Discussions about the side effects from the chewy pearls broke out among netizens.
This was not the first time that the bubble tea business, originating 30 years ago in Taiwan, has been challenged that their tapioca pearls contain harmful substances. We wrote about the bubble tea craze last year, and mentioned the first scare of finding a carcinogen, diethylhexyl phthalate (DEHP), in the chewy black pearls.
After the ban on maleic acid contamination in June, why are we still seeing the bubbles lurking in our cold tea? Is our fear about kidney failure real? We decided to get to the bottom of this.
Are we safe now?
It is common for us to take action immediately after hearing news about what can kill us. However, let’s look into it with a little more detail based on a very simple reason: Bubble tea has been in the market for 30 years. If the chewy balls are going to cause cancer or kidney failure, wouldn’t there be a lot of casualties by now?
We remember how popular they were in pasar malam (night market) 20 years ago when the bubble tea wind blew over to Malaysia. If the claim that the pearls contained maleic acid was true, how did this kidney failing substance make its way to the products? Why would it be used?
Scandals over the years
The first hit – PCBs & DEHP
In 2011, German researchers from the University Hospital Aachen tested tapioca pearls from a bubble tea company in Northern Germany where the brand was originated from Taiwan. The researchers found chemical PCBs such as styrene, that is not approved for use in food because they can cause cancer. However, the report was challenged by a Taiwanese tapioca pearl manufacturer and Taiwan's Food and Drug Administration (TFDA).
In the U.S., the Food and Drug Administration (FDA) quickly put up research of their own. As a result, the U.S. banned a list of Taiwanese foods based on their amount of PCBs. The result of the ban spread like wild fire, causing international media to jump to the conclusion that Taiwanese tapioca pearls can cause cancer.
Taiwanese government then did their own test and found DEHP in products by several Taiwanese food manufacturers. DEHP is widely used as a plasticizer in manufacturing of articles made of PVC plastic. DEHP can be absorbed by food or water and has been limited to packaging only, but for foods that primarily contain water.
The first wave of the health concern scandal for Taiwanese tapioca pearls was nipped in the bud by the government in 2011. Nonetheless, the image of Taiwanese foods had been tarnished. The food scandal was also used against the then government by their opposing party, affected their next election result.
The second hit – maleic acid
Taiwan’s TFDA, discovered through their regular food testing, that the tapioca balls contained maleic acid. The Agri-Food & Veterinary Authority of Singapore proved the existence of the substance and banned the import of some Taiwanese products.
News travelled to Malaysia and the Ministry of Health banned a list of Taiwanese foods. As this hit is still affecting us, we would like to share what we have found about the contamination and what measures that have been taken by the authorities.
First, let’s look at the three possibilities for how maleic acid could contaminate food:
1. The use of the compound itself;
2. Leached from packaging to food;
3. Chemical reaction during production process.
What is maleic acid?
Maleic acid is an organic compound that is used to make lubricant, paint and is a plasticiser for PVC plastic. It should, however, be differentiated from malic acid (notice this without an “e”?), which is a natural compound derived from fruit such as apples. Malic acid is a safe food additive used to give a sour taste, but not so for maleic acid.
The brother
Maleic acid has a brother - maleic anhydride. Maleic anhydride is used for the same purpose as maleic acid, except that it is in dry form and can be used as a food additive in small amounts. Huntsman is the world’s largest maleic anhydride manufacturer. Using maleic anhydride in tapioca balls makes them more bouncy and chewy. To convert maleic anhydride to maleic acid, simply add water at room temperature.
“Maleic anhydride is hydrolyzed to maleic acid with water at room temperature.” - MALEIC ANHYDRIDE, MALEIC ACID, AND FUMARIC ACID By Timothy R. Felthouse, Joseph C. Burnett, Ben Horrell, Michael J. Mummey, and Yeong-Jen Kuo.
You see why it is causing a bit of a concern.
But before you go back to your favourite bubble tea joint and cry for a replacement kidney, let’s look at some facts in a public report by the Taiwan Government:
In Taiwan, adding chemicals to starch to change their viscosity, texture and stability for use in food is allowed. Permits are given to approved food additives. However, starch modified with maleic anhydride is not permitted, as its metabolic mechanism is not clearly understood.
If the Taiwanese government does not approve maleic anhydride modified starch, why are the pearly bubbles still lurking in our cold tea? The answer is: Taiwan has declared that there is no more maleic acid contaminated tapioca pearls and none will be produced again.
What did Taiwan do?
1. After the allegation, an investigation was immediately carried out on all products involved.
2. Affected products were recalled, sealed and destroyed within a week.
3. An affidavit to the sellers was provided by the food manufacturer to ensure safety of their production. – to seal this matter once and for all.
4. An overall inspection by the health authority started on 1st June 2013.
5. Added a chapter to the Act Governing Food Sanitation for food safety management, food import management and food testing, strengthened domestic food businesses management, imposed heavier penalties, and provided protections for whistle blowers.
6. Is working towards having government agencies for chemical management, food exporting, and public communications to work together.
Within 2 weeks after the outburst in Asia, the whole situation was under control and there was no more news about bubble tea pearls causing kidney failures or cancer.
The scare of kidney failure caused by tapioca pearls has dissipated. The Ministry of Health Malaysia has issued the list of banned products and measurements taken on 3 June. After that date, no products produced in Taiwan will contain any maleic acid and if the substance appears in any imported products, they’ll not be allowed in to the country. We shall be at ease about going back to our 3pm daily routine of drinking bubble tea, for now.
If you are still worried…
a) Check with your doctor.
b) Do some calculation:
According to the Ministry of Health Malaysia, “those who have consumed the products need not to worry as irregular consumption of a very small amount of maleic acid will not affect their health”. But how much is “small’’ amount”? We found a calculation in the report from the Taiwan Department of Health (4 June 2013) pertaining to the contamination of maleic anhydrite modified starch in food:
Based on the standard set by European Scientific Committee for Food, a tolerable daily intake (TDI) of 0.5mg/kg of consumer’s body weight of Maleic Acid and Maleic Anhydride is safe.
- Calculation of TDI based on a 60kg adult: 0.5 mg/kg × 60 kg = 30 mg/day
So assuming a tapioca ball contains 400mg/kg of maleic acid, more than 75 g tapioca balls would be consumed every day over a long period of time to exceed the TDI.
- 30 mg/day ÷ 400 mg/kg = 75 g/day
That is equivalent to 250 tapioca balls per day!
The other health concern
We are more worried about the health effects from the starch and sugar in the tea than the contamination. According to myfitnesspal.com, a serving of bubble tea can contain over 500 calories. We suggest consumption in moderation and this should apply to everything, really.
Discuss this topic and see what others think about it on our drinks forum.