Use this entry on address bar for references: Ptfe finishes on cooking utensils
I've yet to see any thought on paper about the waste of material, energy and money that is caused by the kitchen culture adherence to non-stick cooking utensils.
The food safety of Teflon and Ceramic finishes is widely discussed.
What seems definite is that these finishes fail around two years time and that if used with too high a heat setting this damage is hastened and the safety of the food is seriously compromised.
There is a fundamental and serious element of self-defeat in applying a non-metal surface to a metal one which is to be heated and that is that much more heat has to be applied. In the case of ceramics it is indeed these which are used to insulate from heat and I would expect this too, though to a lesser extent ptfe finishes.
Common advise is to buy upmarket so that the coatings and the metal beneath are thicker and longer lasting - thicker means more insulation and though it may last longer when it goes it goes for ever and the pan is thrown out - lost forever.
Decades ago, before this non-stick fad a good saucepan or pot would last decades - I can remember as a kid in the 40's repair kits for holes appearing after many years of use, like 10 - 20 at least, and the repair giving more years after that.
The cost to the environment is, in summary waste and pollution.
Waste of heat in their use.
Waste of the item when it is thrown away at 2-3 years instead of 20.
Waste of heat and inevitable pollution from an unnecessary coating process which releases toxins.
In the case of cheap pans and that usually means thin or lightweight pans is that the added heat necessary to do the cooking job through the coating distort the base or cooking surface and means oil or fluid from what is cooking puddles and causes uneven cooking.
Expensive pans often offer guarantees of up to decade, not on the surface remaining non-stick but only on the pan not distorting with heat - this is done principally by thickening the base by adding more metal or by laminating with other metals - typically stainless top to an aluminium and/or copper base. These processes are complicated and heat intensive.
Care of a non-surface means considerable discipline and thought and the temperatures advised are easily ignored in a rush. One element of advice relates to oiling the pan after cleaning - so called seasoning of the pan using a small amount of oil - I know this is advised before using a ceramic non-stick pan. In these cases much of the chemistry relating to the so called oil-free interface of food and pan is lost.
It is advisable to not use a non-stick pan over 260 C or 500 F which is where heat degradation of the surface occurs. It is also advisable not to use an oil approaching, at, or over its smoke point.
Butter has, over the recent years, taken quite lot of punishment from the medical press as a saturated fat. Now however, the processing of vegetable oils and margarines has been condemned and butter is seen as a natural and relatively safe product.
The problem is that butter has a low smoke point (150 C). This limits somewhat its browning ability
when kept at a low heat and as browning, searing and sealing of food especially meat is a very popular this might not be an ideal oil.
But is this the case?
When butter is put in a pan and heated it bubbles a little - the water in it being driven off - this is at 100 C and then settles to a flattish brown puddle which, as more heat is applied, starts to darken and then goes on to smoke.
If, as soon as the steam stops coming off the butter, the heat is turned down so there is no colour change it would be reasonable to assume that the temperature is well under 150 C.
That colour change might make it an ideal indicator for the heat to be used for non-stick cookware.
I would almost put money that butter well below it's smoke point would gently brown most protein but I need to show this by experimenting.
However what I hoping to get across is that an ordinary uncoated pan will melt butter just the same and offer very effectively its non-stick properties.
It seems likely that colour change of any heated oil is a reflection that it is being spoiled . Some suggest that if you want to use high heat get an oil with a high smoke point. That seems so very logical but as I've said not advisable to season your non-stick pan and who knows whether that oils
stability at high heat carries some worrying features.
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