Discover everything you need to know about Total Polar Materials (TPM). Plus, how can high levels of TPM impact the cooking oil used in your Commercial Kitchen fryers?

In Commercial Kitchens, maintaining the quality of cooking oil is a crucial part of ensuring fried food is safe and enjoyable for your customers.

According to the German Society for Fats Science (DGF), Total Polar Materials (TPM) is the most reliable parameter for assessing oil quality.

This makes it extremely important to understand what TPM is, how it forms, its potential consequences, and the best practice for managing and measuring TPM levels in your fryers.

What is TPM? 

Total Polar Materials (TPM), also known as Total Polar Compounds (TPC), is the parameter used to convey the percentage of polar substances in cooking oil. Free Fatty Acids (FFA) are a common example of such substances.

Polar substances are formed through the chemical reactions that take place when cooking oil is heated to high temperatures.

The three major examples are:

  1. Oxidation
  2. Hydrolysis
  3. Polymerisation and thermal decomposition

2. Which chemical reactions lead to higher levels of Total Polar Materials? (TPM)

When hot oil is exposed to oxygen, especially at high temperatures, it undergoes a process called lipid oxidation. The outcome? Your oil will develop a rancid odour and an off-flavour.

Hydrolysis occurs when water from food products enters hot oil. As a result, your oil will become more acidic and could develop a lower smoke point. It is also more likely to foam.

Sustained high temperatures can trigger polymerisation and thermal decomposition in cooking oil. This could lead to your oil becoming darker and more viscous. It will also be more likely to foam and smoke.

3. What are the potential consequences of cooking oil having high levels of TPM?

As mentioned above, high levels of TPM can impact the taste, texture, appearance, and odour of the food being cooked in your fryers. This could lead to a rise in complaints, risking the reputation of your brand. It will also make it difficult to drive standards of consistency and quality, especially if your business operates across multiple sites. What’s more, cooking oil with high levels of TPM can negatively impact the efficiency of your equipment and lead to longer frying times, as the oil will have a lower smoke point and will struggle to hold heat. It could even cause your fryers to clog, increasing the need for cleaning and maintenance.

4. What are the UK regulations for Total Polar Materials in cooking oil? 

Across the globe, different parameters are used for the measurement of cooking oil quality (e.g. AV or Free Fatty Acids). However, TPM is fast becoming the most common parameter.

In the UK, there are currently no regulations that set a legal maximum limit for Total Polar Materials (TPM) in cooking oil. 

Instead, UK industry best practice has traditionally aligned with European Guidelines, specifically the EU Food Law (2006) that suggests a maximum limit of 24%. Most European countries work around the 24-27% mark, replacing oil when it gets to this point.

5. How do you measure TPM in cooking oil?

Although some Commercial Kitchens still rely on visual checks for determining the quality of their cooking oil, many sites are moving away from this unreliable approach. Instead of wasting time and money on unnecessary oil changes or risking the quality of their output, they have switched to Food Oil Monitors (also known as Cooking Oil Testers). In around 30-60 seconds, these hand-held devices provide an accurate measurement of polar compounds. There is even a traffic light system operating on the top of the instrument that flashes green if the oil is fine to use, amber if it will need replacing soon, and red if it needs changing.

Learn more about our range of Food Oil Monitors

6. How do I maximise oil life in my kitchen?

The cooking oil in your fryers is always going to degrade over time; however, there are steps you can take to slow this process down. One idea is to closely monitor the temperature of your fryers, this is something Food Oil Monitors can help with, as they also provide temperature readings. By avoiding fluctuations and making sure not to overheat your oil, you can keep TPM levels as low as possible. You can also achieve this through frequent filtration – removing floating debris before the food particles have chance to accelerate the degradation process. The proper storage of your oil and cleaning of your fryers will also make a big difference.

So there you have it, answers to the most common questions surrounding Total Polar Materials (TPM) – also known as Total Polar Compounds (TPC).

We hope this article has provided you with a clear understanding of the journey your cooking oil goes on when heated in your kitchen fryers, and has highlighted the importance of taking reliable and accurate TPM measurements.

If you require any further information about oil management or our range of Food Oil Monitors (Cooking Oil Testers), you can contact us directly on 01473 461 800 or sales@klipspringer.com. Alternatively, you can complete the form below and a member of our team will be in touch.

Not sure when to change your fryer oil?

Speak to our team or request details of our TPM cooking oil testers.