Awesome burger I had last night at db Bistro Moderne in NYC.

[Chicago Bob]

I've heard of folks putting anything from an ice cube to a slab of butter pressed in between 2 patties. Once saw a show where they deep fried a burger in a deep cast iron pan and they said they NEVER change the oil, just remove some as the meat gives off it's fat. Hmmmm!    People sure seemed to go nuts for those burgers...

[TXCraig1]

I've heard of folks putting anything from an ice cube to a slab of butter pressed in between 2 patties. Once saw a show where they deep fried a burger in a deep cast iron pan and they said they NEVER change the oil, just remove some as the meat gives off it's fat. Hmmmm!    People sure seemed to go nuts for those burgers...

In a restaurant, if you use a good shortening such as MFB in a commercial fryer and filter it a couple times a day, you almost never need to change the oil - just add more to replace what leaves with the fried food and filtering. If you're frying heavily salted foods, it might be different.

[Chicago Bob]

In a restaurant, if you use a good shortening such as MFB in a commercial fryer and filter it a couple times a day, you almost never need to change the oil - just add more to replace what leaves with the fried food and filtering. If you're frying heavily salted foods, it might be different.

Is it just an old "wives tale" about how (even well filtered) oil "breaks down" after time and won't heat up as hot (or something like that) ?

[TXCraig1]

Is it just an old "wives tale" about how (even well filtered) oil "breaks down" after time and won't heat up as hot (or something like that) ?

All fats break down over time. Heat, burned bits, salt, oxygen, etc. accelerate the process. Shortening is much more stable than liquid oil. Even in liquid oils there is a wide range of quality with higher quality oils lasting much longer. Regardless of what you use, filtering is key to oil life.

On the other side of the coin, I know places that buy decent quality oil and dump it all every day and start over in the morning with fresh oil because they see doing so as a key to consistent quality.

[TXCraig1]

As oil breaks down, the smoke point may lower, so while they will probably get as hot, it may not be a good idea to do so.

[Chicago Bob]

Thank you sir....

[rcbaughn]

I left my fryer running all night last week at 350, I am wondering if that long of a stint at that temp has ruined my peanut oil? That stuff is expensive and I hate to see a gallon of it get dumped due to my stupidity. Luckily is was on the deck outside though. The color of the oil doesn't look any different BTW, don't know if that matters.

[Jackitup]

If it was being run via thermostat, should be ok, just took a few miles off it. Restaurants keep them going for hours and hours all the time but seldom reach temps over 450. Lucky it did flash on you. If it were a turkey fryer with the burner underneath 'insert firetruck here' so I assume it has a thermostat control 

jon

[Chicago Bob]

For years I've used big box peanut oil, 5 gal. This last time around I switched to soybean oil cause I heard that's what the Chinese restaurants use an I wanted to try and get that "take out flavor" for my homemade egg rolls and tempura stuff that I love. It is a bit cheaper Cory...but I never see it in smaller bottles though.

[rcbaughn]

Yeah peanut oil is extremely high. I think I paid $35 for a 5 gallon container of the stuff a long time ago. That said, I still have some of it left. Lasts a long time in that quantity.