What is the best way to reduce the genesis of oil vapors and aerosols when frying?

Question

I would like to clarify I am not asking about oil splatter nor am I asking about air filtration tools.

What is the best way to reduce the generation of frying aerosols and vapors that can condense on distant surfaces such as those in rooms adjacent to a kitchen without changing cooking temperature or method of cooking, in this case, pan frying?

Is the smoke point of the cooking lubricant the greatest factor for aerosols and vapors or is there something else that impacts it more strongly such as the amount of moisture in the food being cooked which increases the amount of sizzling and splatter which may generate fine aerosols that remain airborne?

Can an oil vaporize without ever reaching its smoke point or is the term "smoke point" synonymous with evaporation? Maybe my question is misguided and oils cannot actually vaporize, but rather only become a fine mist, or maybe the smoke itself is what is sticking to the surfaces as what appears to be an oily film.

Is there an index for different types of cooking lubricants regarding their evaporation points rather than smoke points if they do indeed evaporate?

Answer 1

To address the generation itself: it is up to the food you are cooking. The more moisture it releases, the more droplets you will have.

So, if you are frying something with very little moisture, like old bread to make croutons, you will have fewer droplets. If you are frying a steak, you will have lots of droplets and aerosol. If you are frying food which has been frozen (and is now leaking more moisture), you will have more droplets than if you are frying fresh food.

There are two things that will help to some extent, but not drastically reduce the spatter. One is to not throw frozen food into the pan, always room temperature. And the second is to always use dry food - if you are not layering anything on, pat it dry with a paper towel. If you are using layers, always end with a dry layer such as breadcrumbs or flour.

Since the micro-explosions happen in the water/steam phase (the oil is just being flung around as a kind of explosion debris), I doubt that changing something about the cooking oil will change the droplet generation. Changing the temperature inside the frying pan may have an effect, but it will also drastically reduce the quality of your food.

The phenomenon of oil smoking is unrelated to this kind of greasy aerosol generation. The expanding steam will fling around anything in which it is suspended, no matter if it is burnt oil or unburnt oil.

The only thing you can do about your choice of frying fat is to choose a pure fat - that is, anything beside butter or margarine. If you choose an emulsion of water in oil, you will get more splattering. But all oils, ghee, and animal fats such as rendered lard should give you equal splatter amount.

Answer 2

The oil droplets to which you refer are actually called "explosive hot oil droplets" by researchers who have studied their distribution via fluid dynamics. They are part of a larger group of kitchen air pollutants called "kitchen-based aerosols." You might be interested in this paper, where the authors examine the impact of these droplets on indoor pollution. I can't find evidence that different oils respond much differently, and the solution appears to be proper ventilation. They are not evaporating, but instead being broken into very small droplets, as a result of interacting with high heat and water, which cause them to become airborne. This is why proper outdoor venting recommended.

Answer 3

Venting is definitely the way to go, and as close to the source as practicable (e.g. a cooker hood).

If that's not an option, or not enough, a splatter guard made of thick/multiple layers of mesh (example for illustration - this claims a carbon filter in between mesh layers) should help quite a bit too, by catching some of the droplets (even though they're smaller than the drops that land around the stove). The downside is that when frying food containing lots of water it will keep some of the steam/water in.

Note that when arranging ventilation, you should think about where the replacement air comes from. My house is fairly open-plan, and if I want to keep oil/odours in the kitchen, it's best to turn on the cooker hood extractor and open some ventilation (e.g. a window) in the living room, shutting the kitchen windows tight. This gives a draught so that the area I want to protect is upwind of the source of fumes etc.