The average home cook is just that: average. But not you—you are not average, and neither is your food. So why would you settle for average, oven-baked, store-bought, crinkle-cut fries? You wouldn’t. No, that’s why you’ve started reading our series on homemade french fry cookery. We’re here to travel with you through the realm of critical temperatures to a glorious, golden-brown fry-vana.
At the outset, we have a decision to make: what oil should we use to fry our fries? We need an oil that can handle the high heat of deep frying and that will give us good tasting fries. We need to consider smoke point and flavor profile.
The smoke point
…limit[s] the maximum useful cooking temperature of cooking fats. [It is]the characteristic temperature at which a fat breaks down into visible gaseous products…[and] depends on the initial free fatty acid content of the fat: the lower the free fatty acid content, the more stable the fat, and the higher the smoke point.—Harold McGee, On Food and Cooking, pg. 802
When those “gaseous products” that escape the oil meet a flame, they can ignite. This means that an oil with a proper smoke point for a given task is not just a recommendation, it is a matter of safety.
Plus, when an oil starts to smoke, its flavor changes, tasting burnt, and it transfers those flavors to your food.
Yes, it would be easy to fry your fries in regular salad oil since you have some on hand, but it has a smoke point that is low enough to become dangerous and start tasting bad at deep-frying temperatures. Any highly-flavored seed oil will not work well either, as their impurities lower the smoke point. Case in point: cold pressed peanut oil can hardly be used for cooking at all before it starts to smoke and burn, while refined peanut oil has a smoke point of 450°F (230°C). And since oils start to break down even below their smoke point, we need an oil with a high smoke point for the 375°F (191°C) frying we will be doing.
What we don’t want from our cooking oil is something that will tinge the fries with an unwanted flavors—I’m looking at you, metal-fish tasting canola oil! When people talk about oils, they often refer to them as having a “neutral” flavor, and that’s what we want: a flavor that will not taint the potatoey goodness of the french fries. The reigning contender in this category is the aforementioned refined peanut oil. Long accepted as a standard deep frying oil because of its neutrality, high smoke point, and ready availability (on the bottom oil shelf of most grocery stores), peanut oil is the choice of home fryers as well as chains such as Five Guys Burgers and Fries. French fried potatoes fried in refined peanut oil taste like frenchfries.
(As a matter of interest, pure peanut oil is so free of impurities—i.e. proteins and stray carbohydrates—that it doesn’t even have to be listed as a peanut ingredient for allergen information! You can read about it on the FDA’s allergen page as well as the Food Allergy Research & Education website.)
Of course, if we could flavor the fires with the oil in a way that we liked…well, shouldn’t we give that a try? For that, we can go back a few years and see that the answer for flavorful fries is beef tallow. Tallow (the name for rendered beef fat, an analog to pork’s lard) was used widely for deep frying until as late as the 1980’s, when people suddenly became afraid of saturated fats. It has a distinctive beefy flavor and a smoke point comparable to that of peanut oil. Pioneers fried in beef fat, Mcdonald’s used to fry in beef fat—shouldn’t we try frying in beef fat, too? We should.
So, to settle the question for our future posts, we’ll try a batch fried in the modern standard, refined peanut oil and a batch fried in standard of yore, beef tallow. Along the way, we will try to investigate some of the thermal properties of the oils, to find out if one has a thermal advantage over the other.
In this kitchen trial, we tested the flavor and the thermal properties of beef tallow vs peanut oil to determine whether or not there are culinary or physical reasons to choose one over the other. To test the thermal, we quantitatively measured the heat capacity of the oils to determine which will cook our french fries faster. And of course, we wanted to find out if beef tallow fries—touted by aficionados as being far superior—are better tasting than peanut oil fries.
Heat capacity is the amount of heat energy that a substance can hold. Heat and temperature are not the same thing! Heat is the amount of energy a substance contains, while temperature is how that energy is manifested and transferred. Imagine, if you will, heating a stone and a pot of water of equal mass to 212°F (100°C). If you were to touch them both, they would both start to burn you rather quickly, but the water would do far more damage, because water has a higher heat capacity than stone. It has more thermal energy, so the stone would run out of energy before the water would. (Don’t try that at home!)
What we hope to find is whether or not the beef tallow has a higher, lower, or equivalent heat capacity when compared with peanut oil. Does tallow have more heat in it and can it therefore cook the fries a little more quickly or thoroughly before they begin to get soggy?
- We started with two cast-iron pots of the same size from the same maker. To one we added a weight of rendered beef tallow (1,597 grams), to the other we added an equal weight of peanut oil. Each pot was filled only 1/3 of the way for safety.
- We prepared two equal weights of cut potatoes that had roughly the same surface area. To accomplish this, we cut equal length pieces out of potatoes and cut those into 1 cm x 1 cm fries. (We did our best on this and distributed the fries randomly between piles, to even out any inconsitencies.)
- These were rinsed, dried, and tossed with a little cornstarch to ensure crispness.
- Each pot of oil had a ThermaData™ thermocouple logger probe placed in the oil, for data purposes, and an easy-to-use ChefAlarm® for temperature tracking purposes.
- The thermometers were started simultaneously, as was a TimeStick®, used in count-up mode as a stopwatch. The TimeStick was used to measure key events—like the amount of time required to reach a certain temperature.
- Each pot of oil was placed on an identical burner stove, and each burner was turned simultaneously to high heat. Both ChefAlarms were set to 325°F (163°C)
- When each pot reached 325°F (163°C), an equal weighted portion of potatoes (472 grams) was added and cooked for 5 minutes as measured on a TimeStick.
- The fries were removed and spread on wire racks, and the heat turned off under the oil. The oils and the fries were allowed to cool for 10 minutes.
- After 10 minutes, the heat was re-ignited under the oil.
- When the temperature of each oil reached 375°F (191°C), the fries were added back to the oil and cooked until golden brown and delicious.
- The homemade french fries were strained, salted, and set out for tasting.
We hit an unexpected problem with the beef tallow. Despite the dryness of our fries and the shallow depth of oil in the pot, the tallow foamed and bubbled so much that it threatened to overspill the edges of the pot. We quickly turned off the flames under the tallow pot each time the bubbling tallow threatened to reach the top of the pot. We experienced this same phenomenon on each of multiple fry cooks with tallow. Stay tuned for more on this effect in subsequent posts as, with the help of some food scientists, we explore why this occurs and what can be done about it.*
But because of the burners being turned off for a few minutes each time, the temperature data on the beef tallow became skewed.When we killed the heat and moved it off the burner, the temperature was allowed to fall quite rapidly, as it was not supported by the flame without interruption as was the peanut oil pot.
The final color of the cooked french fries was similar, as was the crispness of the two versions.
That being said, we can see an interesting piece in the data we were able to salvage from the boilover.
You can see in the chart the time after we added the french fries to the oil. Both the peanut oil (yellow line) and the beef tallow (orange line) temperatures start to drop, but the beef tallow temperature drops more slowly. As both pots had the same amount of oil and the same amount of fries, this tells us that the tallow was losing fewer degrees of temperature for every bit of heat energy given away, i.e. the tallow has a greater heat capacity. The same can be seen after the second heating when the fries were cooked the second time (starting at about 32 minutes for peanut, 36 minutes for beef tallow): the peanut oil temp dips, the beef tallow temp stays fairly level, and even increases. The rapid decline in temperature thereafter was a result of removing the oil from heat.
Fries fried in peanut oil are delicious and everything we expect from a good fry, homemade or not! But the beef tallow fries had something else, a richer, deeper flavor that was just a little bit like eating fries made from potatoes that had been cooked with a pot roast. They were not astoundingly better, but the meatier flavor was appreciated and more satisfying than the peanut oil fries. One ThermoWorker liked the peanut oil better, but the rest liked beef better.
While the flavor of the beef tallow fries was somewhat better than that of the peanut oil fries, and the thermal capacity is also slightly better, the very dangerous possibility of burning your house down if your tallow were to bubble over into the flame when you add the potatoes means I cannot do anything but recommend the peanut oil—at least until the foaming problem is resolved.
Add to the safety issues the fact that peanut oil is easy to find, whereas beef tallow must either be purchased from a specialty vendor (or a very well stocked butcher), or rendered at home—a time-consuming process, the smell of which will only make you want a cheeseburger the whole time—and peanut oil is the clear winner. Conventional wisdom here prevails, and we can safely say that high-heat peanut oil is the best oil for frying your homemade french fries!
We got hold of an oil scientist, Dr. Oscar Pike of Brigham Young University, and posed this quandary to him. In conjunction with his advice, we diluted the rendered beef fat with 10% peanut oil. We tried a batch of fries cooked with 1500g home-rendered beef tallow and 167g peanut oil.
You see, peanut oil has a lower viscosity and a lower surface tension than beef tallow. By adding the peanut oil, we lowered the surface tension of the overall batch enough that the foam was NO problem! Plus, with a 90% beef fat ratio, there was no lack of good, rich tallow flavor.
By mixing the oils, we severely diminished one of the dangers of frying in beef oil, and preserved the advantages, including a higher heat capacity. While peanut oil is still easier and cheaper to find and buy, we recommend giving the diluted beef tallow method a shot, as it produces superior tasting fries.
Whatever you cook with, the key to good crispy homemade french fries is careful temperature control. And unless you have any ThermaData loggers in your cupboard, a ChefAlarm (and pot clip) set to a high temp of 375°F (191°C) and a low alarm of 350°F (177°C) will do the trick!
What about using refined avocado oil? It has a higher smoke point than refined peanut oil, I believe.
See the reply above to Kenyoni. But I have never personally seen refined avocado oil. I would not be surprised by a high smoke point, I just have no idea where the average consumer can get the stuff.
Les C. from woodland ca. says
When you re-test the tallow could you include duck fat in your test? Duck fat fries using russets are really good.I do not deep fry just shallow saute.
See my reply above to Nancy. I’m afraid duck can’t quite handle the high heat for the deep fry! A shame, because pan fired duck fat potatoes really are great stuff.
Mike Harney says
I’m looking forward to your further study of tallow misbehavior. Directly related to this: If you haven’t already, I highly recommend two episodes of the most recent series of journalist Malcolm Gladwell’s “Revisionist History” podcast, which are all about McDonald’s – and others’ – abandonment of beef tallow for fries in the US, why it happened, and how it’s recently been discovered that, while their move was well-intentioned, it may have been about as dubious as it gets. The episode descriptions from the site:
209 McDonald’s Broke My Heart
McDonald’s used to make the best fast food french fries in the world — until they changed their recipe in 1990. Revisionist History travels to the top food R&D lab in the country to discover what was lost, and why for the past generation we’ve been eating french fries that taste like cardboard.
210 The Basement Tapes
A cardiologist in Minnesota searches through the basement of his childhood home for a missing box of data from a long-ago experiment. What he discovers changes our understanding of the modern American diet — but also teaches us something profound about what really matters when we honor our parents’ legacy.
Mike Harney says
Whoops – I just looked at the link in your article and you’ve already referenced Gladwell. Please feel free to delete my comment.
I let it stand, just in case people don’t click on my link for it. Interesting story, isn’t it!
Chris Camillo says
Great research article I have blanched thousands of pounds of FF maybe 350F is the answer to beef tallow’foaming issue? It would achieve 2 goals: slightly longer fat life & slightly less high heat activities – foam over.
if the foaming was happening at 375°, I would hope 250° would be the solution, but the foaming was happening most at 325°, with the secondary fry going pretty smoothly (some foaming, but not nearly so much). And if I can’t fry at 375° with an oil, I am not going to use it for fries. They need that high heat for maximum crispness.
Dan Wolfe says
I’d be curious to see you test avocado oil, which seems pretty neutral to me, and also has a very high smoke point. I love using it for sauteing and pan-frying.
See my answer above to Kenyoni. The smoke point is a little too low for my liking.
Veronica Miller says
Where do you find Beef Tallow?
I rendered it myself. I bought fat from local butcher shops and kettle rendered it. You can buy it from local butchers, at farmers’ markets, or online. Like I said in the post though, I don’t recommend it for the fries based on safety concerns. If you just want some tallow for other things, making it is a pretty good way to go.
Mike Cernak says
I am a serious french fry nut, and started experimenting to find the best way to cook them in the ’70s, while still a teenager. I started with a pot on the stove and frozen fries, and used a thermometer to monitor the temperature. At once, I saw the oil temperature drop from 350° to 250° when the frozen fries were added, and started using the double dip method to cook them.
One time, the pot caught fire when the fries were added and the oil started spitting. I put the lid on and no damage was done, but after this I switched to electric deep fryers. I found the highest wattage fryers were best; no surprise there. But home fryers of the time still had the heating element in the base, so they heated the pot, which then heated the oil. This made the sides of the pot very hot, and the oil that spattered while the fries cooked fused to the sides of the vessel.
I realized this was why commercial deep fryers immersed the heating element in the oil, rather than heating the pot. So I bought a small commercial counter-top fryer that ran on 110V and took 1850 watts. This fryer held about 20 pounds of fat and took a half an hour to reach 350°, a decided disadvantage. The oil temperature still dropped significantly when fries were added, though not as much as with a smaller unit.
Even though fairly large, the machine was easy to clean. I bought a second pot so I could filter the oil a few times before changing it.
About this time, I also switched to fresh-cut fries. I tried several small french fry cutters before settling on a large commercial device that worked like a champ, even with very large potatoes. I would make 20-30 pounds at a time for parties, holding the fries in water until they were ready to be fried, and keeping the cooked fries under a commercial warming lamp.
I also found “blended” frying fat at a local Chicago restaurant supply house. Available in fifty pound cubes, it was 50% beef tallow and 50% vegetable shortening, and solid at room temperature. This provided most of the flavor benefits of beef tallow with none of the drawbacks. It was also cheaper than just about any other type of fat or oil.
Finally, a few years ago, they started making small versions of commercial fryers for home use, with the heating elements immersed in the oil. This was now perfection. The smaller quantity of oil they used only took five or ten minutes to reach 350° and recover the temperature after fries were added. These things also took much less counter space. I kept my old commercial fryer on a wheeled stainless steel cart that also held the warming lamp.
Nowadays, I no longer buy the blended shortening. I tried a five gallon jug of Mel-Fry from my local warehouse store, and it works OK.
One thing I would suggest to people who like french fries: try making your own potato chips. Use a mandoline to slice the potatoes thinly. I use the V-Slicer, which is incredibly sharp, and slice the potatoes directly into the oil, which I saw a diner in Two Rivers, WI doing. Stir to keep the potatoes separated for a minute or two, then fry until crispy.
Also, use a light dusting of popcorn salt on the chips rather than regular salt. Rather than use the tiny 3¾ ounce shaker, buy the one pound box and pour it into a Cambro shaker with a green (96SKRLF407 superfine) or beige (96SKRLD406 fine) lid. The superfine is REALLY fine and hardly anything comes out even with vigorous shaking, so I use the beige lid and shake carefully. Popcorn salt is also best for french fries.
One last tip. I don’t use the french fry cutter any more, now that I no longer make fries for large groups. I cut the potato into wedges. First, cut them into quarters lengthwise, then make the wedges. This uses the entire potato with no waste, and all slices are the same size, which ensures even cooking. The french fry cutter would leave smaller pieces from near the potato’s surface, which I used to fry separately from the big center pieces.
There you have it. One man’s lifetime journey through the world of french fries.
That’s a fantastic journey! thanks for sharing your expertise with us!
What counter top fryer did you happen to buy? I’m so tired of soggy fries and am an absolute fry nut. I’m from Toronto so I need to ask, if you ‘had to buy’ fries, which ones would you buy from your grocer? Hopefully my Walmart carries the fryer you going to report back on. Thx.
You’ve got to be kidding. This is one of the big reasons why home insurance is so high. (Let me say that I am being polite in this post.)
well, we did recommend against using the more dangerous oil. Now people don’t have to try it themselves and burn themselves down.
Ray Chan says
Thank you for your little study. When I was younger, McDonald’s made the best french fries. There was nothing comparable. I remember when they moved away from using beef tallow. The fries were good, but never matched the deliciousness of fries when cooked using beef tallow. I don’t know the science behind this or secrets they hid, but it made a difference. Too bad. There was a French Restaurant in DC that came very close to duplicating the McDonald French Fries (can you imagine that). They were hot and delicious and wonderful with their steaks. But alas like many good things the old McDonald fries and this fine eatery are gone. The youth know not what they miss.
If you hear of another eatery frying in beef tallow, let us know!
James McDevitt says
In your Jan. 10 “Golden and Crisp” article you suggest an initial low of 325 but in your Jan. 19 “Choosing the Right Oil” you suggest a low of 350. Which is to be preferred?
I actually recommend 325° in both posts, but as you saw in the graph, things got a bit hectic in the kitchen and one pot got up to 350° for the initial fry. If it had been the beef-pot, I’d have had to start over again, but as we were looking mostly for flavor variants and the reaction of the oil to heat, we were ok with a known oil getting a bit hot. Nice catch, though! 325° is definitely the way to go.
randy bell says
Such a great article! You guys are the best and make me not want to buy any temp related products anywhere else. What a great company! Whoever is in charge of e-communication should be well compensated so as not to lose them.
John Howard says
All the rendered animal fat I’ve ever used to fry will foam up at first, but after a few rounds it will stop. Seems that the oil wants to combine with the water in the food and it foams up. In time it breaks down I guess.
Good to know! I will continue to learn about it and see if we can’t clear this up even more!
Douglas Purcell says
Great study. No wonder I like Five Guys french fries best. I have a 6 gal fish fryer and I have the same questions about which oils to use when frying fish. I think the fish would taste better in peanut oil but I am afraid that some people would be allergic to the peanut oil. Do you have any studies about which oil to fry fish in?
I have often used corn oil for a fish fry, and recommend it heartily as a backup for peanut every time.
What about the comment above regarding allergies? “(As a matter of interest, pure peanut oil is so free of impurities—i.e. proteins and stray carbohydrates—that it doesn’t even have to be listed as a peanut ingredient for allergen information! You can read about it on the FDA’s allergen page as well as the Food Allergy Research & Education website.)”
Wade Nikota says
Great info on fried
Do you ever do deep fried steak or pitch fork steak if so what oil would you try or mix of oils for flavour
I’m not going to lie, I’d never heard of the pitchfork steak fondue. Now I feel a deep need for this in my life.
No, I’ve never deep fried a steak, but if I was going to, the same kind of rules would apply. If I was going for flavor and I had a cauldron big enough to handle this whole affair (with boil-ups and foaming and all the associated problems), I’d probably go with a mix of beef tallow and bacon grease-for flavor. But that much tallow is going to cost. Maybe 50% peanut, 40% tallow, 10% bacon grease. BUT BE SAFE. this is an answer based on flavor only, and I have no idea how a steak thrown into such a pot would react.
DB Wright says
Why not compare more normal oils against peanut oil – such as Vegetable oil, Canola, etc., etc..?
We were limited by time and space. I recommend looking at a good smoke-point chart like this one from Serious Eats. I personally think that canola oil, while neutral at room temp, tastes (and smells) terrible when cooked at high temps, so I wouldn’t use that one, but that may be subjective. Try some things out, let us know what works best for you!
Laura Hansen says
What if you mixed the peanut and beef tallow? Maybe get the good properties of both? Would there be any danger in doing that? Just thoughts, and maybe a suggestion for future article?
we are considering a test on this!
Try adding 1/2 cup bacon fat to the peanut oil as recommended by Cook’s Illustrated to give the fries the meaty flavor the beef tallow gives.
Nancy Tomlinson says
what about duck fat?
Well, that would obviously be DELICIOUS, if it could work. Potatoes fried in duck fat are a classic dish, but those are usually pan-fried. But Duck fat itself only has a 375°F smoke point, so it’s probably not a great idea for deep frying like this—it would be burning the oil while cooking. Plus, I don’t know if duck fat will have the same foaming reaction when used for the initial blanch. If only, if only!
Brandon Colbert says
Great experiment and article. I love fries, I love frying food, I love my thermoworks instant read thermometer, but I suck at it. My fries never crisp up like I want and the flavor is good not great. Recently, I’ve been soaking the potatoes in leftover beef fat that I keep frozen in ice cube trays and then thaw when needed, and corn syrup. Flavor is actually really good but crisp texture is lacking. I’ll pay much closer attention to my temperature control during both fry stages and I think it should pay dividends. Thanks again for the info!!
Good writeup. Not too long ago, I had lunch with my Mom where they used tallow to cook their fries. It was one of their signature dishes. Those fries were the bomb, way better than anything in recent memory.
Further testing is warranted in this most important quest. What about a blend of 75% peanut oil (for safety sake) / 25% beef tallow (for flavor)?
This is a thought I have considered! If I try it out and there are interesting results, you will hear about it on the blog!
I am surprised you did not use refined coconut oil also in your comparison. Taste from one food does not transfer to another, good smoke point, oil does not boil over, long lasting, and cheaper than peanut oil on Amazon if buying Nutriva Organic by the gallon.
Refined coconut oil is a pretty good idea, as it is neutral and has a high smoke point, We could not test every oil, of course, but if you are able to get it easily and at a price that is good for you, go for it and let us know how well it turns out!
Adam R says
I would think mixing the two might be an excellent compromise, and reduce foaming considerably.
That is a though I have had, and I might head down to the demo kitchen to give it a try. If I do and the results are newsworthy, you can be sure I’ll write it up on the blog here!
I’ve read that McDonald’s used a 93% tallow, 7% cottonseed oil mix. If true, what was the reasoning? Could it help the oil from bubbling over? Seems like too like oil to significantly raise the smoke point or control costs (if cottonseed oil was a cheaper oil than tallow, that is).
I base my oil on McDonald’s, switching grapeseed oil for the cottonseed (same neutralness and high smokepoint, but healthier), and never experience the same furious foaming and bubbling as described here. I do two fry sessions, though, after partially cooking in salt water/sugar/baking soda mix. The first fry is at 290F for around 5 minutes, until the fries start to appear dry, then I freeze for a minimum of 1 hour, and then I fry for just under 2 minutes at 375F. That process could hinder the bubbling over as well.
I meant it seems like too little cottonseed oil to raise the smokepoint.
sound like you’re quite the fry expert! Way to go! I imagine the McD’s mix was based on cost more than smoke-point alteration. And I suspect the foaming problem may have to do with the purity of the rendered tallow. Home rendered fat has a lot more proteins left in it than the stuff purchased through, well, rendering companies. I’m still waiting on a food scientist or two to back me up on that.
Thanks for sharing and happy cooking!
I’ve only used home-rendered tallow. Slow cooker method. I strain it through cheesecloth and a tight wire mesh strainer, so I can’t imagine it’s too pure.
That’s what I used, too. I wonder what the difference is?
Patrick Rogers says
What if you are allergic to peanuts?
According to the USDA, refined peanut oil is not a peanut allergen—and you know what sticklers they can be about safety and labeling! You know how a can of peanuts has a little warning on the back that says something like “allergen information: contains peanuts” or how even something without peanuts might say “processed in a plant that also processes peanuts”? well, the FDA doesn’t require such a label on refined peanut oil!
Of course, you should never do anything you don’t feel comfortable with, and I don’t want you to die if yours is a different breed of allergy than most. So if your allergist says it’s a no-no, try substituting corn oil. It has a great smoke point and a good flavor. It is a bit more expensive, but will do a fine job.
beef tallow used to be McDonalds secret ingredient awhile ago. Added a unique taste to their fries.
I’d really be interested in the results using avocado oil.
If you can find refined avocado oil, I’m sure it would work great, but most avocado oils—valued for their flavor as well as their nutritional worth—have a smoke point right at 375°F (191°C) (depending on manufacturer and process). This means your oil would be burning at the same temp as your fry cook. I have never personally seen highly refined avocado oil in the supermarket, but I cannot help but think it would cost a LOT. If you find some, try it out and let us know!
Could you please cite a reference for your numbers? According to The American Oil Chemists’ Society, unrefined avocado oil has a smoke point of 200-250°C , (400-480°F ) (depending on manufacturer and process).
Refining can take it up to 520 °F (271 °C).
Amazon.com shows all 4 types, (Pure, Virgin, X-Virgin, Refined) ranging from USD $35-$60/gal.
I see that you have better info than I! I was going from a chart given on SeriousEats, a source that is often very trustworthy. I take back my accusations of the oil that it is not up to the frying challenge. Give it a shot and tell us how it goes!
I see that you “dried” your fries, but insufficient drying could be the cause of your tallow foaming issue. I was having the same problem and my old uncle who has a lifetime of experience with tallow told me to dry them in the fridge uncovered for a few hours. That did the trick. Using this method, they do turn out to be crispy on the outside and fluffy in the middle, but it also adds a lot of time to the process.
I am interested to see if this makes a difference, I doubt it will. It seems that the engine for foam production was actual steam escaping from the inside of the fries, which would still happen even with super dry fry exteriors. But if it works for you, then good man!
Elaine of Astolat says
“…the very dangerous possibility of burning your house down if your tallow were to bubble over into the flame when you add the potatoes means I cannot do anything but recommend the peanut oil—at least until the foaming problem is resolved.”
Why lead your answer with some hyperbole about burning down your house? Simply suggesting a larger pot or mentioning just to be extra careful resolves the foaming “problem”. The whole point is to make fries that taste good, and a boil over with peanut oil is just as dangerous. If the beef tallow makes the better fries, then it is the better oil for making fries.
It may not be the most convenient oil—though expensive, it is readily available on Amazon— and people will take that into account.
Also, if you continue the research, the tasters should not know which fries were fried in which oil. That knowledge will tend to skew their opinions.
Otherwise, this is a great article, thank you for it!!
Thank you for your comments! The bit about burning your house down is sadly not hyperbole. Thousands of home fires each year are started by improper deep frying.
A larger pot could fix the problem, but judging by the amount of foam-up, it would need to be significantly bigger. I have seen peanut oil boil ups and I have seen this, and this was far worse than any peanut oil reaction I have ever seen.
Believe me, I want a way to do this safely, but people need to know the very real risks. I, of all people, am not one to shrink from a better tasting oil, but the safety is important here.
Also, none of the testers knew beforehand which fires were which. We didn’t want skewed data!
Thank you for your responses and than you for reading, we hope to have this tallow issue ironed out soon!
Suzanne Oppenheimer says
Have you tried rice bran oil? It’s great for tempura.
I have tried it! It is wonderful stuff, but hard to get in gallon jugs, at least where I shop! I love it for stir-fry dishes in particular.
I render tallow and am guessing it was not purified enough/still too wet.
After straining with a colander and then a fine tea strainer add it to a large pan with vinegar and water and simmer for a few minutes to pull impurities out then let cool. The tallow will solidify on top with the impurities caught in the water below. Pull off and dispose of the water. You know you’ve done it right when the tallow is near white rathet than yellow.