Deep Frying Basics

“It doesn’t matter if it’s boiled or fried
Just eat it” – Weird Al

 

With all due respect to Weird Al, it does matter. Deep Fried is the ultimate for crunch and keeping juice in when done right. And speed, never forget how quickly your food cooks when you deep fry it. We’ll lead you through some background, some science, with some tips and tricks, all focused on deep frying at home safely and with great results.

Deep Fried History

Somewhere, sometime, someone said let’s chuck this dough into that bubbling hot fat to cook it. Likely a couple thousand years BCE, in Canaan they surmise. The oil was probably lard of some sort, although extracting oils from plants was also a thing by then.

Deep frying was later the western world’s contribution to Asian cuisine, starting with the Portuguese bringing tempura to Japan sometime in the 16^th century.

Like most cooking techniques, deep frying has a place in every course of the meal from appetizer to dessert, snacks to buffets. Just in case there was any doubt, the state fair circuit in America has proven you can deep fry just about any food product you can think of. Other than Antarctica, every continent enjoys food from a fryer.

Deep Frying Science

You can walk out in 115-degree heat and feel it, but it is not painful. Most people will yank back their hand if they put it in 115-degree water. The difference is the amount of contact, water touches every inch of exposed skin, directly moving the heat to your skin whereas the air has so few molecules, relatively speaking, that the heat transfer is less. Same idea when you immerse food in hot oil, full contact with the heat. That is why you get faster cooking speeds and other affects.

A large part of why food browns when exposed to heat is explained in the Maillard reaction. We don’t know all the whys behind it, but the French scientist was the first one to really examine and track the reactions of the sugars, enzymes and other food components. These are what give us all the great flavors and textures of fried, baked, or any style of cooked food that browns.

Types of oils for deep frying

Effective deep frying occurs between 350-375°F. This is the temperature at which you get the best balance between removing moisture and not absorbing oil in the food.

All oils have a smoke point and a flash point. Which is why some oils are not good for deep frying.

The smoke point is when they begin to scorch, obviously beginning to smoke a bit.

Flash point is when they burst into flame.

Don’t exceed the smoke point, the easiest way to avoid learning the flash point.

This table shows the smoke point of commonly available oils.

Fat & Oils Smoke Points

Refined canola oil is by far the most common oil used commercially for deep frying in our experience. As you can see, it has a very high smoke point. Peanut oil is arguably the best choice, light flavored and sturdy, it has some great qualities. It is also kind of expensive relatively speaking. Beyond that you see a lot of refined sunflower, soy or corn oil blends available for restaurants and home frying.

Batter VS breading

Simply put, batter is wet, breader is dry. You can bread something with an already damp surface by simply dredging it through flour or such until it is coated. That flour coating will also allow a fluid to adhere better. So, to batter fish for example, you dredge it to coat with flour, then put it in the batter until coated and then place in the fryer. A breaded product can also be dredged, then it gets a wash layer, typically beaten egg with a little water, then dredged in the final coating of more flour or bread crumbs, crushed corn flakes, or many more choices.

Potatoes and flour-based foods like doughs or pasta do not require an extra coating step. They have enough starches to resist shrinkage, and keep their moisture levels. Think that through, and you see why we tend to use flour based breadings and batters to coat food before frying it.

Frying Safety

You can certainly deep fry food with just a pot and a heat source. First off, mind the temperature. As we just explored, there are specific windows of temperature that are safe and get you good results. Here are the other considerations to stay safe.

Every Thanksgiving we hear about someone burning up their place while deep frying a turkey. Excluding dopes who drop a frozen bird into hot oil, the most common mistake is because of displacement and bubbling. When you first put food into a fryer, you get this really cool mild roar of bubbling oil that can come up as much as six inches across a deep turkey fryer, and similarly a pot of oil on your stove. Combine that with displacement raising the oil level when you add stuff to it and that’s where the danger starts. Turkey frying is typically done over an open propane flame, which will light oil on fire if it overflows down the sides.

The lesson learned is to leave enough room for displacement, meaning how much your food will raise the oil level. And secondly, allow for bubble up or foaming of at least a few inches. Just to be safe, right before you add the first batch of food, turn off the heat. No open flame on a gas stove, or hot element on electric, to cause a flame. If it spills over you just get the mess to clean up in your non burnt down kitchen.

Equipment for stove top frying

If you are using a pot on a stove you want to be sure that you have tall enough sides for the reasons we just mentioned. Ideally you want a basket of some sort that fits easily in the pot, and allows for a decent cooking area. There are purpose-built stove top deep fryers available, and basically you are emulating one with a basket in your pot. You can fry without the basket insert, but having it makes your life easier when it comes time to take the food out.

There are great tools for handling deep fried food during cooking. Spider strainers, slotted spoons, or mesh strainer spoons are all made for pulling food out of a fryer with minimal mess.

The other piece of equipment that you will like having is a mesh cover to diminish splatter and grease vapors. Frying is messy, and will distribute some oils particles in the air, and leave a scent; all of which the mesh cover will help reduce.

Complete home fryer

If you plan on doing a lot of deep frying, there is a lot to be said for getting a dedicated unit to use. Generally, these will plug into the wall, freeing up stove space for other things, and letting you decide where you want to do your frying. In our case, that means the back patio, under cover if needed, so the smell and mess stay outside.

These will have a fitted basket for removing your food when cooked. They will also have a fill line that will help you be safer and neater by avoiding any spill overs. Investigate the ease of cleaning and such if you want to make a purchase, that is an area they will differ greatly and you will appreciate the ease of a well-designed unit.

Oil filtering

Every single time you use your fryer you really want to filter your oil. You can use a simple fine mesh metal strainer to remove enough debris to help your oil live longer, just wait until the oil has cooled enough to handle safely. This will provide you with two solid benefits. The first is that you will extend the life of the oil immensely. Properly filtered, you can use oil again and again, in the neighborhood of 10-20 uses.

Filtering will allow much less flavor influence from past frying to stay in your oil when cooking again. Unfiltered oil will have particles that get very overcooked as the oil is reheating, causing a scorched or chemical flavors to your oil. In some cases, large particles can contribute to your oil going rancid quickly, adding horrible flavors and the risk of making someone sick. For taste, wholesomeness and efficiency, filter after every use.

Go forth and fry!

Have fun, stay safe and experiment. There’s great premade food to fry from the grocers, and then your limitless imagination to explore