How to keep my (deep frying) oil usable as long as possible?

Question

I have a new deep fryer. I am pleased with its results so far. I am not a 'heavy user' though - say once every 2-3 weeks. I want to re-use the oil a couple of times. The deep fryer is covered but not airtight, however.

The new deep fryer has a cold zone, which means the oil won't become dirty due to particles over-frying. I don't overheat the oil either. So, in principle, I'm frying correctly, I think.

So, how long can my oil safely sit in the deep fryer, if I ensure it's thouroughly heated next time I fry? Should I be allowing the oil to cool and store the fat in (sealed) containers instead, if there's going to be this long a gap between uses?

Edit: yes, I've seen this question and answers: http://cooking.stackexchange.com/questions/3014/frying-oil-reuse

Asked by Tobias Op Den Brouw

Answer

First thing, a cold zone doesn't prevent particulate build up, it just cuts down on the amount that will remain suspended in the oil. You should still filter if you want to keep your oil as long as possible. You can detect bad oil (meaning rancid) by a few ways, like smoke point or smell.
You should store your oil someplace dark and cool, which could be the inside of your fryer as long as you filter and clean the sides before you stick the oil back in. Another thing you can do to extend the life of your oil is switch to tallow (beef fat) or rended pigs fat (lard) as saturated fats do last a lot longer than the poly-unsaturated.

Once again, you should lose the oil when the smoke point drops, or if it is to dark, or if it develops any foul odor. And as I said before, once you use the oil once, you should NOT use it past six months under any circumstances, if you do, you are taking your gastro-intestinal tract into your own hands.

Answered by sarge_smith

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what's the smoke point of a hybrid oil?

Question

I saw at the store there's a new cooking oil composed of 80% canola oil and 20% olive oil. They offer it for frying and seasoning. What would be the smoke point for such an oil?

Asked by Dan

Answer

It would be the smoking point of the lower of the two oils.

There is a persistent myth among cooks that mixing two fats somehow makes for a better smoke point (usually oil+butter). But the molecules which will burn at 150°C will always burn at 150°C, no matter what other molecules they are mixed with. So, if you mix two oils, and oil X has the lower smoke point wlog, it will smoke at the smoke point of oil X. It will smoke less than pure oil X, but only because you have diluted it and you have less low-temperature-burning molecules in the pan.

This doesn't mean that the smoke point of your mixed oil is too low for frying. The smoke point of cold extracted oils is always low. But it is possible to refine olive oil, even though nobody sells it pure (the advantages of olive oil are removed by refining). If both oils in your hybrid oil are refined, it will have a high smoke point, suitable for frying. But marketing doesn't always care about such details, so, if they don't say anything more specific on the label, you can't know what kind of olive oil (or canola, for that matter) they used. From a cynical point of view, this is a perfect way to get low-quality olive oil, refine it, and sell it for frying hoping that the customer will choose the frying oil advertising "olive oil" among its ingredients, but there is no proof that this is what the producer is doing.

Answered by rumtscho

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Crispy cheesy snacks for dieters

Question

I am going to experiment making a savoury cheese crispy snack like Twisties or Cheezels. I have these ingredients in mind.

Corn, Vegetable Oil, Rice, Whey Powder, Cheese Powder (parmesan), Vegetable Salt, Cream Powder, Milk Powder. I will experiment with onion, lemon, lime and chili flavourings.

My question is this. Which of all the vegetable cooking oils is the least fattening? Please do not recommend Canola (aka rape seed oil, as I have heard negative facts about this oil)

Is it possible to source an oil that is nutritious as well as low fat? Or maybe I should just be happy with the healthier options of fatty acids?

Asked by Carol

Answer

All vegetable oils are 100% fat, and have 900 calories per 100 gramm. It is not possible to reduce an oil's fat content by diluting it, this is only possible with hydrogenated oil (margarine). But low fat margarines are not suited for frying.

When dieting, you have two concerns. First, if you eat more calories than you use up, you get fatter. Second, if you eat just enough, but the weight regulating mechanisms in the body are not in "shedding fat" mode, you don't lose weight. Changing the oil has absolutely no effect on the amount of calories, you just have to restrict the amount of snacks to reduce calorie intake.

The second point could be influenced by oil choice, as different plants deliver oils with different types of fatty acids, and they could have different effects on body chemistry. But discussing such nutritional topics (not the calories count, but the effect of different food on body chemistry) is off topic here on SA, so if you asked more about this, your question will be closed. Anyway, I doubt that anybody here has such information at all. You either need to look it up in a nutritional information source you trust, or just pick any oil. The amount you can consume on a diet is so small that it probably won't make a difference.

Answered by rumtscho

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Making “french fries” out of Cassava/Yuca root

Question

I'm surprised this question isn't already on here, maybe I missed it...

To start, had my first taste of yucca cooked as a sort of alternative french fry at a Bolivian restaurant, and it was delicious. Reminded me of a tastier, sweeter french fry. So inspired by this, I bought some myself and attempted to replicate it, but utterly failed.

What is the best way to replicate the recipe? After watching a video on youtube of how to prepare it, I deep fried it in oil, but it overcooked much too quickly.

UPDATE:

I tried out the selected answer's recipe yesterday, and it worked fantastic. I did a few things differently though, mainly due to time constraints. Full recipe:

1. Cut off brown skin.
2. Slice into steak fry slices
3. Boil for 10mn (I would suggest less, some thinner slices became too soft)
4. Blanch (I only had time for 20-30 mn, but I'd go with the full hr if you have the time)
5. Heat Peanut oil (Med-High) in deep cooking pot (can get messy) and cook until brown.
6. Sprinkle with salt

Note: The answered recipe suggests frying until golden/golden brown, but I found a darker fry to be much tastier!

Asked by JWiley

Answer

This is how my mom prepares it (she's from Brazil, so it might be a tad different):

1. Cut off all the dark brown skin
2. Wash it and put it into a pot of water and bring to a boil
3. Boil for about 10 minutes (it should still be slightly firm, but not hard)
4. Cut it up into french-fry sized pieces
5. Put the slices in a single layer on a cookie sheet and place in the freezer for about an hour
6. Heat oil, fry them for about 10 minutes (until golden brown)
7. Sprinkle with salt

Steps 1-5 can be done ahead of time and you just pull out what you need from the freezer to fry. I have not personally made these, but I ate hers a lot and they were fantastic!

Answered by Michael

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What's the proper way to dispose of used fats & oils?

Question

Down the drain? Does it depend on the type? With bacon fat, I usually let it solidify in a cup lined with foil, and then throw it out. With used canola oil, I'm not quite sure what to do because it doesn't solidify.

Asked by Knarf Navillus

Answer

Never down the drain. We've had a few incidents in my neighborhood where the sewer pipes were clogged with fat, and a few people's basements flooded with sewage as a result.

For fats that solidify, let them do so, then pitch them in your regular garbage. Chill it in the fridge if you need to get it to harden up. For ones that don't, I put them into a sealable bottle, and pitch them that way, but it's possible that your area might take it as part of a recycling effort.

(ours does for motor oil; I've never checked at the drop off site if they take cooking oils or not).

update : I was answering this assuming this was a question for home chefs; for restaurants, some places (eg, the state of Maryland) require a system for catching grease that's been washed down the sink. It's my understanding that they're fairly expensive (a couple thousand dollars US), but the fines for not having one installed may be even more, and they won't let new restaurants open without one.

Answered by Joe

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leaving oil on a frying pan for use later

Question

I live alone, so I cook for myself. And often times I cook steaks/burgers on a pan, and later in the same day would return to use the same pan/oil without washing/using new oil.

Is this safe, or should one wash and use a new pan before cooking every steak/burger patties? I've actually done this for more than a day once (cooked burgers in the morning, steaks later that afternoon, and then burgers for the next morning).

Asked by kamziro

Answer

If you preheat the pan then you should be perfectly safe as the high heat should kill anything 'dangerous' before you add your meat for the second meal.

That said, I would point out that those oils left out are likely to begin to degrade immediately, causing your steak to take on some potentially undesirable FLAVORS.

Answered by Cos Callis

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What oils are suitable for Indian cooking (i.e. extended frying duration)?

Question

Indian cooking basically uses oil from the beginning of the process, typically starting with sautéing ginger and garlic, then adding shallots, chillies and onions. So the oil is on the fire for quite some time.

I would like to know whether any type of olive oil will be suitable for this type of cooking. Extra virgin olive oil seems to be out of the question from what I have read.

Asked by jogabonito

Answer

With Olive oils, the more refined they are, the higher their burning point. So you are correct, an Organic Extra Virgin Olive Oil would be a terrible choice for Indian cooking (would cause effect on taste, smell, and nutrition) which has prolonged periods of sauteing on high heat.

Lower quality olive oils, or a light olive oil, interestingly, would be a better choice. They are much more refined like vegetable oils, so have a higher burning point. But at that point, you'd consider why are you using Olive oil?

Consider using refined butter (ghee) or coconut oil for Indian cooking. Ghee and Coconut oil will rarely smoke or burn and can stand high heat pretty well. I believe traditional Indian cooking uses ghee.

Answered by Swati

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My pesto turned solid. Why?

Question

Warning: I am a cooking noob. I might overlook something ridiculously simple.

Anyway, I just made my first pesto sauce (do you call this a sauce?). Basil, Parmesan cheese, garlic, etc. At the end, I added vegetable oil. All was good and I was proud. Put it on bread and on pasta, and it was very tasty.

However, I stored what I had left in a small jar in the fridge. Only one day later, and it became solid! You can clearly see that the oil had solidified. Why is this? In fact, I poured in too much oil and took some out, and what I took out I put it in the fridge, in a cup (just the oil). This is also one massive block. I am used to oil solidifying, but AFTER you use it to cook. The oil that I used has not been cooked, and the rest of the oil I bought at the store is stored in a cupboard, in its original packaging, and is still liquid.

What went wrong?

Extra question:

• Can I somehow still de-solidify this and still eat this?

Asked by user16441

Answer

Most pestos use olive oil, which solidifies at around 6 degrees celsius - just over the temperature of the average fridge. The shop-bought pestos you buy probably adulterate the olive oil with other kinds of oils.

In any case, you'll be able to eat your pesto just by leaving it out at room temperature for a few hours, or by just scooping it out and adding to your hot pasta.

Answered by Jimmy Breck-McKye

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How to clean a clogged Misto oil sprayer/spritzer?

Question

I use a Misto oil spritzer. You fill it up with oil and pump it up and spray a pan with it.

It's gotten clogged up so that it just squirts a steady stream of oil (not a spray).

Any ideas how to clean it and keep it from clogging again?

I've tried:

• Soaking it on wine
• Soaking it in boiling water

I'm going to try filling the bottle with vinegar and water. I've also heard that you should use regular (not extra virgin) olive oil. (Extra Virgin is apparently thicker).

Asked by Clay Nichols

Answer

I generally clear my clogged misters / spray nozzles by unscrewing the spray part from the bottle and then submerging the uptake tube in very hot (but certainly not boiling!) water and then pumping as long as it takes to clear the clog out and start spraying a mist / spray pattern again. The hot water should be enough to break up the clogs, and the pump action should force the clog out.

Answered by Katey HW

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What can I substitute for vegetable oil in a recipe?

Question

Is there something that I can use as a substitute for vegetable oil in a recipe? I'm actually making cornbread (I think it matters), and normally the recipe calls for 1/3 cup vegetable oil. Unfortunately I just realized that I'm out. Can I use butter or shortening instead? If so, roughly how much would I try?

Asked by Andrew Dunaway

Answer

On first blush, you will probably want a fat or oil with similar qualities as the "vegetable" oil you're replacing, such as olive oil. Butter has a much lower a smoke point, however, cornbread recipes exist that use butter or lard. I'd be willing to experiment, particularly if you're used to cooking with butter. (Just be careful with heat.) As far as quantity, I'd use a bit less than 1/3 of a cup, but that's me being defensive as I don't know the recipe you're using.

Answered by staticsan

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How can I save my curry - it's way too oily!

Question

I cooked a chicken curry in the slowcooker last night, I came down this morning and its way too oily. I think because of this the coconut milk has separated a little too.

Any way I can save this, even a little?

Thankyou

Asked by serenskye

Answer

Allow it to cool, then put it in the fridge for a few hours. The fat should rise to the top and harden, making it easier to scoop away.

If you can't wait for it to cool, either skim the oil off with a spoon or use some kitchen paper to soak it up.

Answered by ElendilTheTall

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Can oil be replaced with yoghurt in a cake recipe?

Question

A cake recipe is asking for "one cup" oil!!

I don't want to eat so much "oil", can I replace it with yoghurt or something else?

Asked by Anisha Kaul

Answer

Short answer - not really. Fat is an essential component in any cake, and milk just isn't very fatty - about 5% for whole milk. You can make cakes with milk, but they require totally different recipes: you can't simply substitute milk for oil.

Bear in mind that you're distributing the cup of oil throughout a whole cake, so that any one slice will only have a fraction of the oil. I assume you'll also be sharing the cake with others, so you'll be 'spreading the calories' somewhat.

You should be using a relatively healthy oil like canola (rapeseed) oil anyway, as it has a relatively mild flavour. A popular alternative these days is to substitute all but a couple of tablespoons of the oil with apple sauce (really), but this can be hit and miss and doesn't work with all recipes - it usually works best with things like quick breads (scones etc).

Of course, there's also the point that cakes are supposed to be a treat, and they'd be less of a treat without the fat, in which case why bother? If you want to be healthy, make a salad. If you want a treat, make a cake and don't worry about the contents too much.

Answered by ElendilTheTall

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Which oils are considered flavorless?

Question

The cake recipe is calling for a vegetable oil. I have refined sunflower oil, and refined soyabean oil.

Do they qualify for flavourless oils? I haven't noticed any taste in any oil by now! Taste buds problem, perhaps.

Asked by Anisha Kaul

Answer

Both refined sunflower oil and refined soybean oil are generally considered flavorless.

Also included among these are:

• Canola (rapeseed) oil
• Corn oil
• Peanut oil
• Safflower oil
• Vegetable oil

The most reliable method of course is to taste the oil :). I'm sure you can actually taste the flavor of extra virgin olive oil.

Answered by hobodave

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Annatto Oil Substitute

Question

We have a recipe that calls for us to make annatto (achiote) oil and fry some chilli peppers in it. We are unable to find annatto seeds. Is there a good substitute?

Asked by Joe Johnson 126

Answer

can you even find the whole annatto seed? that's what makes the oil that color. i don't think it really imparts a much of a flavor. a thread at chowhound.com suggests maybe using turmeric instead to color the oil -- i can see a bit of a resemblance.

Answered by franko

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What limitations are there to sauteeing with water?

Question

I was recently helping with some recipes and was instructed to use water for "sauteeing" onions, celery, garlic, etc in place of oil (scare quotes on "saute" since it involves frying in oil or other fat by definition).

The technique is meant to parallel sauteing in oil, water is measured by the tablespoon in a large pan, and although you replace waster as it evaporates the vegetables are never submerged in water. Only enough water is ever used to inhibit sticking of the vegetables to the own.

The results were good and light but I haven't had much of a chance to push it further and experiment with the upsides and downsides (the three dishes meant to just soften the onions, garlic, celery and I had to follow the directions). Obviously, using oils imparts that flavors that you otherwise won't have present if using water. More importantly though, I would like to know which reactions would be inhibited in some way; for instance, would browning and carmelizing happen at a different rate, or at all? Are there any other preparations that would be impossible without a fat to saute in? What are the limitations when using water to saute?

Asked by mfg

Answer

The big difference is that oil can get to a higher temperature than water can. Water turns to steam at 212F, while most oils won't start smoking until 300-400F. Caramelization doesn't happen until 320F (for sucrose and glucose, 230F for fructose), while browning (the Maillard reaction, to be specific) doesn't happen until 375F. Now when you "saute" like that in water, you'll also be using the steam to cook, and the steam will be somewhat hotter than 212F, but probably not enough hotter (or in enough quantity) to get to those reaction temperatures. You might get high enough temperatures via direct contact with the bottom of the pan, but that's a recipe for uneven cooking, as the part of the food actually in direct contact are likely to be quite small.

Answered by Dave Griffith

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Stir-frying: how much of the oil evaporates?

Question

When you're stir-frying or sauteeing, I'm sure some of the oil get evaporated due to high temperature. How much of the original oil evaporates? Since I suppose it depends on the kind of oil, temperature and duration, can you give example for several typical cases? (for example, vegetable oil, medium heat, 15 minutes, etc)

How does this affect the nutrition and energy calculation? For example if 50 grams of vegetable oil contains ~400 kcal, how much calories does some food cooked with that much oil has?

Asked by Fitri

Answer

The boiling point of most cooking oils is much higher than their smoke points. The boiling point of olive oil, for example, is around 300°C (572°F), which is hotter than the temperature of a pan on a typical residential range/cooktop. With that said, alcohols and esters which make up the flavor and fragrance of the oil will have lower boiling points and will therefore evaporate. That should not significantly alter the nutritional content of the oil. Furthermore, much of the perceived loss of oil is likely due to a combination of absorption of the oil into the items being fried, and also due to splatter. The latter cannot be easily quantified due to its connection with the cooking vessel and the technique of the cook.

Answered by ESultanik

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No oil on non-stick pans?

Question

My boyfriend is convinced that a non-stick coating on a pan (Teflon, seasoned cast iron, eco-ceramic, what have you) is equivalent to eliminating the need for using any cooking oil whatsoever.

Is this in fact the case? I'm fairly sure that it only reduces the amount of oil necessary to keep things from sticking, but I'm having a hard time proving this (other than the empirical tests that keep failing). Essentially, he is a huge fan of fried eggs, but is trying to avoid the eventual heart attacks.

Asked by Hannele

Answer

There are two parts to this question, the stated part, and the unstated "are you really frying an egg if there is no oil?"

For the first part, most manufacturers of non-stick pans claim that their product makes oil unnecessary, and generally I've found that to be true. A little oil helps, but "necessary" might be a stretch.

To maximize your non-stickyness of a non-stick pan, you should always preheat the pan before adding the food, at least to 250F or so. Preheating causes the teflon to expand a bit, closing up pores and micro-scratches in the surface.

It is also common for oils from the past to form a polymerized layer on top of the teflon, making the pan more sticky. This is actually worse when you use aerosol spray oils, because the tiny droplets hit the pan and very quickly polymerize to form a slightly sticky layer. This layer is similar to the one you intentionally create when seasoning a cast iron pan, but in this case it is not helpful. All-Clad recommends periodically cleaning teflon pans with a light scrub of baking soda and water to remove that coating of oil. It should bring back the maximum slippery of your teflon.

When cooking protein-rich foods, you can also minimize sticking by letting the food cook a bit before attempting to move it. The loose, floppy denatured proteins in an egg are extremely sticky, but when they coagulate (set) from cooking, they become less sticky. It may seem impossibly sticky at first, but may release on it's own after a minute of cooking.

As to the second, unstated part, oil provides flavor, and is also a heat-transfer vehicle. When the food is on the pan, if you looked at it with a microscope only a small portion of the food is actually in contact with the pan. Those areas will get heated more, and other areas will get heated less. A little oil fills those gaps, causing more even thermal contact, which allows fried food to fry, rather than just get burned in some areas.

It is really a matter of taste whether the flavor of the oil and the way that it changes the texture of the food is appealing to your boyfriend. I wouldn't like it without any oil, but if he does, well, so be it. If he doesn't really like the taste, but is concerned about health, I'd suggest using a little olive oil - it has no cholesterol, is low in saturated fats, and has a good flavor. Different than butter, but still very enjoyable.

Answered by Sam Ley

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Need to refrigerate vinaigrette?

Question

I've made a red-wine vinaigrette dressing using olive oil (which makes up the majority of the dressing), red wine, garlic, and basil.

My problem is that whenever I take it out of the refrigerator, especially when it gets low, the olive-oil leaves it practically solid. I understand that this is normal for olive oil, but it is rather annoying having to get it out 30 minutes before I make a salad or a sandwich (as I don't normally have that kind of time).

My question is, since everything in there but the garlic doesn't need to be refrigerated, is it safe to leave it out of the fridge and let it stand at room temperature? Or is it like all other (store-bought) dressing where after opening (mixing) it requires refrigeration?

Asked by Mike S

Answer

Yes, you should refrigerate it.

Once a commercially bottled dressing is exposed to the air it is contaminated. Your homemade dressing is no different, and is likely more contaminated to begin with. The bottom line is that your dressing is food -- for humans, bacteria, and mold. It might not be the most hospitable of environments, but something is bound to find a home there. This process is arrested by refrigeration. Additionally, the garlic and basil will be going through a decay process that would be delayed by refrigeration.

I'm not sure what kind of olive oil you used, but I've never had a vinaigrette turn solid in the refrigerator. If you're in a rush I'd suggest submerging, or running hot water over the bottle you store it in to quickly thaw it. You'll shorten the shelf life, but if you're using it frequently enough (used all in less than a month) that shouldn't matter.

Answered by hobodave

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What oil is best for seasoning a cast-iron skillet

Question

I just cleaned up a rusty cast-iron skillet and I would like to season it. The thing is that I don't have lard handy and I'm wondering whether any of my other oils and fats would do.

I have: canola, olive, sesame and almond oil.

Also, I've heard that appying the oil and reheating multiple times improves the seasoning. Is it true? How many times does it make sense to repeat the process?

Asked by ddimitrov

Answer

This question has been answered several times as part of more general questions about seasoning. See the (closely) related links in the related questions list. This one in particular: What's the best way to season a cast iron skillet?

Specifically about oil- you want to use an oil that has a high iodine value: http://www.journeytoforever.org/biodiesel_yield.html#highiodine

Of those you listed canola (rapeseed) would be highest. If you can find soybean oil it would be even better.

These oils polymerize more easily. To create an even coating with good adhesion, multiple thin coats work well. I have read of people doing as many as 6 coats but, in my opinion, you should do at least 2 or 3.

Answered by Sobachatina

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Does flaxseed oil need to be refrigerated?

Question

I bought a bottle of organic flaxseed oil to season some cast iron, and the store keeps it in the refrigerator. Does flaxseed oil need to be refrigerated, or is this just a silly thing that the overpriced organic grocery stores do?

Asked by Neil Fein

Answer

Flaxseed oil goes rancid quickly, and refrigeration slows down this process. So, yes, you should do as the label says (usually a good idea anyway) and keep it in the fridge.

Answered by Bob

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