Total Polar Material 24TPM Diminishes Fried Food Quality
The Force Within Frying
TPMs stand for Total Polar Material. At the heart of frying is the force field called the Leidenfrost Effect. This force field is made up of steam. Here is a bit more chemistry, water is polar and oil is non-polar which is why they don’t mix. Every time you put a new basket of food into a fryer you have a new source of fuel for the leidenfrost effect.
As the oil in a fryer moves through the cycle, it brakes down from hydrolysis, oxidation, and thermal alteration. These 3 causative agents produce 13 known compounds. As the chemistry of deep fat frying is very complex in nature, we can simplify by calling all of the compounds total polar material. The creation of these compounds causes oil degradation and loss in food quality. TPMs can produce very rapidly, some would say exponentially, in conjunction with certain effecting variables. As TPMs are produced they combined with oil molecules through a process called polymerization.
Quality in Frying is all about Polarity
As TPMs or total polar material connect with oil molecules through polymerization, the oil becomes polar. For every one (1) TPM that is measured with a TPM testing machine, your oil has gained 1% polarity. 13.5 TPM would mean your oil is 13.5% polar. The international community established at the 7th international symposium for deep fat frying in 2000 that 24 TPM is no longer fit for human consumption.
When a frying vat reaches 24 TPM or higher, that means that 24% or the correlating percentage of oil is polar. A quarter of the oil in the fryer vat or more, now has the ability to pass right through the Leidenfrost effect. The force can only repel the oil for so long. As the moisture reserves are exhausted in the food the force of the steam shield lessons. The weight of the oil is a constant pressure. The polar, non-polar aspect of the Leidenfrost Effect is extremely effective when it comes to keeping oil off of food. The Leidenfrost Effect protects two ways. One is the sheer force of the steam exiting the food. The second is the fact that water is polar and oil is non-polar which does not allow them to mix. The food starts off with an impenetrable shield that gets less and less effective as the TPMs increase.
24 TPM is that start of a nasty impression
You can not see total polar material in frying oil without a tpm tester. When oil reaches 24 TPM and higher, there is a nasty bitter after taste that coats the throat. Fried food is deceptive in that even at 24 TPM and higher, when you first eat it, it tastes just like fried food, yummy. It generally takes 7 to 10 seconds for the nasty bitter after taste to be detected. Depending upon how high the TPMs are, and how long TPMs have been high in that vat dictates how fast the onset will be and the severity of the nasty bitter after taste. It will linger for about 5 minutes and there is nothing except time that diminishes it.
When people get a meal from a burger joint, they generally get fries as the side dish. The first thing they do is grab some nice hot salty fries and start chomping. Then they either take a pull off their pop, or take a bite of their burger. By the time they are drinking the soda or eating the burger, the nasty bitter after taste starts to be noticed. They have no idea what it is from, but they know they don’t like it. The body knows when it is being poisoned and there are volatile compounds created in the chemistry of frying.
The impression left is horrible and can’t be explained as to what caused it, but the customer knows they did not like the experience. This causes them to remember the restaurant negatively, even though they could not exactly tell what was wrong. Everything just tasted nasty, awful, bad! That last impression is what slows down or completely stops repeat business. If a restaurant is not monitoring TPMs they cannot protect customers from the nasty bitter after taste.
Fry Right Quality Cycle Monitors Total Polar Material!
TPM monitoring is currently helping fry right system operators achieve consistent quality cycles all cycle long. These quality cycles range from 7 to 14 days. A fry right quality cycle means that day 14 looks as good as day 2 and tastes as good as day 1