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An important safety notice has been issued worldwide for use of the Thermomix TM5 and TM6 by its German manufacturer Vorwerk Elektrowerke.

Owners of both the Thermomix TM5 and TM6 models have been advised they should use the simmering basket instead of the TM6 measuring cup when cooking at temperatures of 95°C and above to avoid the risk of uncontrolled spillages and potential burns.

CHOICE believes that although the Thermomix manufacturer has been proactive in dealing with the safety issue, the solution it's offered is imperfect and consumers may be entitled to a refund.

On Vorwerk's Thermomix Facts website the company states, "We have observed a few cases in the market where a problem has arisen when using the Thermomix."

The company explains that when the standard measuring cup is inserted in the Thermomix TM6, it fits tightly in the lid, preventing it from falling out when the mixing bowl lid is removed. The measuring cup on the TM6 is designed so that sufficient steam from the mixing bowl can escape at the edges when cooking or simmering. 

However, during the cooking process or when following certain recipes, ingredients can float to the top, become compressed and prevent steam from escaping. 

Pressure can build up in the mixing bowl during cooking or simmering, which can lead to a sudden and uncontrolled spillage of hot food

Consequently, increased pressure can build up in the mixing bowl during cooking or simmering (or heating at temperatures of 95°C / 200°F and above), which can lead to a sudden and uncontrolled spillage of hot food, which can cause burns.

This situation does not arise if a TM5 measuring cup is used, as the measuring cup for the TM5 sits loosely in the lid of the mixing bowl. Users of a predecessor model should check if they are using a TM6 measuring cup. If you own a TM5 and have never upgraded your measuring cup to a TM6, then the warning won't apply.

You can differentiate between the TM5 and the TM6 measuring cups as the TM5 cup is clear, and the TM6 cup is a solid dark grey.

Read more: Should you buy the Aldi Stirling Thermo Cooker?

The new guidance from Thermomix states that when cooking (simmering) at temperatures of 95°C or above (200°F), the simmering basket should always be used as the 'lid' instead of the TM6 measuring cup. The simmering basket rests loosely on top, is steam-permeable, and also prevents food spatter from the mixing bowl. 

If you follow recipes in the Guided Cooking feature, the software has been modified so that all affected recipes in Guided Cooking have been updated with the new instructions. You'll be prompted with the safety alert and to update your software when you turn on your Thermomix and connect it to Wi-Fi.

CHOICE home economist Fiona Mair says, "It's important to follow the new cooking instructions when using a Thermomix to avoid any safety issues. Make sure you connect your appliance to Wi-Fi and read and implement the new software update when the alert shows up."

People who don't use the Guided Cooking function will need to pay extra attention.

"If you use a physical Thermomix cookbook, you currently have to adapt the instructions yourself. If the recipe directs you to cook at a temperature of 95°C or above, you'll have to remember yourself to use the basket instead of the measuring lid," she says.

"If you're using your machine manually, reduce temperatures once any food you're cooking has reached boiling point, and follow the maximum capacity grading so you don't overfill your machine."

Fiona says that Thermomix owners may find having to use the simmering basket instead of the measuring cup inconvenient, as the simmering basket is bulkier and could be trickier to clean. 

You can find more information and some FAQs at the Thermomix Facts website. 

The simmering basket must be used instead of the TM6 measuring cup when cooking at temperatures of 95°C / 200°F and above.

The Thermomix is an expensive machine, with a price tag of more than $2000. It's billed as an appliance that makes cooking easier, and therefore appeals to people with a wide range of abilities who are attracted to its hands-free guided cooking features, and its ability to do a range of tasks from chopping, mixing and kneading to boiling, sautéing and steaming.

Several users on the Thermomix in Australia Facebook Group are disgruntled with what they believe to be a 'band-aid' solution to the latest safety issues, which sees the onus being placed on the customer to change the way the machine was originally intended to be used.

"I purchased a product and I expect it to function as originally advertised," says one customer.

The added effort in cleaning the simmering basket is also a sticking point. It's bulkier than the measuring cup with ridges that food can get stuck in, and it takes up more space in the dishwasher. 

"As a family of seven with lots of dishes to fit in the dishwasher I am not impressed one bit with now needing to find space for this every time we use the thermie, which is daily," says another customer.

I purchased a product and I expect it to function as originally advertised

Thermomix maintains that using the simmering basket in place of the measuring cup will have minimal effect on cooking results and that they've adapted recipes accordingly. But some customers have noted that as more steam than usual will escape during the cooking process, the texture or consistency of food such as sauces or soups may be affected. 

If customers recently upgraded from a TM5 to a TM6, they can use the TM5 cup in the TM6 machine, though this would mean if they wanted to sell their TM5 secondhand it would be missing the cup. 

Many people are calling for the company to provide all customers with a TM5 measuring cup, but at this stage there appears to be no plans to do so.

The Thermomix software has been updated and you must indicate that you have read the safety warning to use the machine.

CHOICE consumer policy adviser Patrick Veyret says, "While it's good that Thermomix has addressed the safety issue and provided a solution, the onus is now on the consumer to fix the problem by changing the way they use the machine, which isn't ideal."

This current issue with the Thermomix could arguably be classified as a major problem if the customer would not have bought the product had they known about the problem. 

A problem is major if at least one of these applies:

People who've bought a product with a major problem are entitled to a refund under Australian Consumer Law. Read more about your consumer rights. 

This is not the first time Thermomix has experienced safety issues. After CHOICE's long-running investigation into Thermomix safety issues, the ACCC took the manufacturers to Federal Court where they were eventually fined $4.6 million. 

The Court found the Australian-based sales team for Thermomix violated consumer law by failing to report dangerous defects.

If you own a Thermomix and you're affect by this safety notice, we'd like to hear from you. Visit the CHOICE Community forum to have your say or email us on newstips@choice.com.au.

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