Can anyone elaborate on why low & slow results are different from high & fast cooking?

[Lars Axelsen]

Sorry if this newbie question has been asked before, but could not find an answer via the search.

I am very curious to why you get totally different results using low & slow as opposed to higher & faster?

When cooking a pork tenderloin on the grill using indirect heat (and smoke) for a about 1½-2 hours at 225F until core temp is about 190F, I will get a very nice and juicy dinner. But if I cook it at direct heat for 20-30 minutes it will be dry and boring at the same core temp of 190F. Same with a pork roast in the oven - if I give it 320F for about 2 hours until core is 190F and use the broiler to get the cracklings puffed, then I have a juicy roast. But using the traditional roasting method with 400F for 1h 15 min and using broiler, renders the meat dry. It is nice to know how to cook better using low & slow, but I really would like to understand why this happens...

So I'm wondering why the big difference in results happens?

I know that high & fast can make it easier to overcook the meat, but assuming we hit the same core temperature, why is there such a difference? I assume that temperature, time and total energy transfer are variables in this as explained in Meatheads book, and that energy transfer at different temperatures may be both different and non-linear curves, but if we hit the same energy transfer by having the same core temp, why is there such a difference in juiciness? Is it related to the fact that surface area meat transfer heat to the core meat which is mostly water, and temperatures too high will evaporate more water than those just above the boiling point?

Cheers, Lars

[lemayp]

See if this article has some of what you are looking for https://amazingribs.com/more-techniq...cooking-temps/

[Starsky]

It has nothing to do with your question, but I can't believe you get juicy meat taking it to 190F. I would typically shoot for 140F in the center when cooking a tenderloin.

[Smoker_Boy]

ItsAllGoneToTheDogs - That's a very good point.
My comment was directed towards the fact that we (Amazing Ribs) tend to go off track with how we cook things while disregarding the OP's specific questions.

At the time I made my comment, 4 out of 6 replies dealt with IT temperature only.

[ItsAllGoneToTheDogs]

Smoker_Boy fair point

[Lars Axelsen]

Starsky - Since pulled pork is taken to 200-210F (I believe), I went for a little lower as I like to slice the pork. Before testing on the tenderloin, I used pork butt with same temperature - super juicy, but took a long time due to size and collagen. So I thought it could be tested with shorter time on tenderloin. Both worked fine and may be juicier as many suggests at even lover temp. Mostly I go for 170F which is where the pork is fully cooked and very juicy (don't like pork to be pink).

[DaveD]

Temperature is one variable, but the composition and structure of what you're cooking is equally important for this question. Pork tenderloins and loins have little connective tissue, whereas a pork butt, for example, is loaded with it as well as more fat. It takes time to render that fat and allow the connective tissue to get tender, it doesn't just occur once a given temp threshold is reached. This is one reason why a stall on a big cut like a butt, brisket etc is our friend, those processes can go to completion. Same is true for holding a big cut after it has reached target temp in some kind of insulated space - briskets and butts really benefit from a couple of hours of hold after target is reached and the meat is probing tender.

The article linked above is a very good summary and will no doubt lead you to other info here and elsewhere too. Yes, it's a question that gets covered here regularly, but everyone has to start somewhere, and one thing that sets this community apart is you will not find anyone who will be critical of questions coming up like this. Anyone who does behave that way is reprimanded and, if need be, shown the virtual door. It almost never happens in the first place though - this is a fine bunch of folks

[LA Pork Butt]

I am no expert, but some meats are going to benefit from hot and fast cooking while others will benefit from low and slow. So, I think your comparison of taking a tenderloin to 190 using the low and slow verses hot and fast does the meat a disservice. A tenderloin will do best cooked hot and fast to 140 or so. In both your tests 190 is over cooked. It would probably be better to do your comparisons with the appropriate finished temperatures. A lot has to do with the breaking down of connective tissue over time. A hot and fast pork shoulder taken to 190 would result a burnt and crisp exterior while a low and slow would result in a tender and moist piece of meat. Incidentally, I get good results cooking them at 225 and taking them to an internal temp of 200. After that I wrap them in aluminum foil and hold them in an ice chest for 2 hours.

Have fun in the Pit!

[Lars Axelsen]

LA Pork Butt - good points. I may have mistaken the temp when converting from C to F, so I took both a pork butt and tenderloin to 170F as I read that pulled pork is taken to above 200F. I like slices better so after the success with pork butt I tested with tenderloin as it is much smaller and faster to cook. Got the near same juiciness even without the connective tissue in the tenderloin, which is why it had me wondering. In the past, grilling a pork tenderloin usually ended up dry.

[RonB]

It's magic!

Ok - it's not magic. Are you pulling the meat out of the cooker at 190°? I ask because there will be more carry over at a higher temp. An example would be cooking something at 225° vs cooking the same item at 300°. There will be more energy stored in the meat near the surface at the higher temp, and that energy will cause the internal temp to rise more than if it was cooked at the lower temp. Try leaving your thermo in the meat after pulling to see how much additional rise in temp happens. The meat will continue to rise for a bit, and then it will start to fall. The high point is one factor in how juicy the meat remains.

Edit to add that I pull lean pork at 140°. It's juicy every time at that temp after rising between 5° and 10°.

[WayneT]

I agree with previous posters that the max core temp of a pork tenderloin of 145F, for maximum juiciness and texture. As to the hot and fast vs low and slow, it basically comes down to type and cut of meat and final desired temp as DaveD so eloquently explained above.

[bbqLuv]

IMHO--Cooking is about time and temperature,
low-and-slow barbecuing is preferred for its juicy, flavorful results, while hot-and-fast cooking offers quicker turnaround but sacrifices some tenderness and smoke flavor. Choose the method that best suits your preferences and available time!

Low-and-Slow:

• Cooking Temperature: Typically between 220°F and 250°F.
• Cooking Time: Takes 10-12 hours or longer.
• Flavor: Results in a smokier, beefier flavor.
• Tenderness: More tender, especially in the brisket point.
• Juiciness: Naturally tender and juicy.
• Smoke Ring: Has a more prominent smoke ring.
• Bark: Develops a more robust bark.
• Total Cook Time: Requires a full day or longer.

Hot-and-Fast:

• Cooking Temperature: Higher, typically between 350°F and 400°F.
• Cooking Time: Shorter, ranging from 3.5 to 6 hours.
• Flavor: Has less smoke flavor.
• Tenderness: May be less tender, especially in the brisket point.
• Juiciness: Can be made more moist and juicy by injecting with broth or marinade, wrapping during cooking, and salting the day before.
• Smoke Ring: Not as prominent.
• Bark: Less developed.
• Total Cook Time: Takes half a day or less.

[Meathead]

I think your guidelines may be focused on smoking. I would disagree on the 10-12 hours cooking time. I start thick steaks at 225 and then reverse sear over max direct infrared. Takes less than an hour. Same for tenderloins. I do things like flank steak hot and fast over direct infrared and IR is measured in watts not F or C. Just as hot as possible, lid open, done in 15 mins or so.

[bbqLuv]

Meathead It was focused on smoking larger cuts of meat.

[TxF]

The fast to 190 is the issue. If you go slow to 190 you probably get enough ‘bark’ to seal in the juices. When you do that fast you don’t have any ‘bark’ and you are just over cooking it. I do pork tenderloins probably fast, don’t really know the temp of to the side with the slow and sear. I take them off about 135 and they are always juicy and you can taste a bit of smoke.

[CandySueQ]

Melt collagen (low and slow), melt fat (hot and fast) for a quick answer. This applies more to pork butts and brisket than other meats.

[Lars Axelsen]

Thanks for all the replies! I will test again with tenderloin at 140-145F core temp using both methods to see if the results are different. The reason I went to 170-190F first on a pork butt was to not only make it juicy but also tender like it is done with pulled pork (which I like less). Then I tested to see if the same could happen to tenderloin even without the need to break down collagen or if it would dry out, but same juicy result. So that had me wondering...

[TxF]

On the tenderloin, I would pull it @135, it will continue to heat up after you take it away from the heat.

[Meathead]

Agree. Tenderloin is done at 135. This is the most tender muscle on the animal so not much collagen or fat. It is very lean so it really is not ideal for pulled pork.

[Meathead]

Short version: In general, low and slow works best for almost everything. Almost. High heat causes proteins and muscle fibers to shrink and squeeze out water. It also cooks more evenly. High heat is what you need (actually infrared is what you need) to get a good seared crust. Usually the best method is reverse sear. Start low and slow and finish hot to sear. There are of course exceptions, especially with thin cuts. May I humbly suggest you buy my book? https://amazingribs.com/ratings-revi...meathead-book/

[Mosca]

“It also cooks more evenly.” You mean low heat, correct? Because the last subject referred back to was “high heat” in the previous sentence.

[Meathead]

Yes, I mean that low and slow cooks more evenly.

[Lars Axelsen]

Got it already as both print and audiobook

[Meathead]

Excerpts from my next book: When you are shopping for a grill, don’t be swayed by a manufacturer who says “our grill can get up to 600°F.” He’s talking about hot air and he’s talking with hot air. The temperature of the air is not that important. We need to know how much energy is produced. We love hot air but if you want to sear a steak you need direct infrared (IR) radiant energy or conduction energy from hot metal, not hot air. A lot of grills just can’t get it up. And if you love great steaks or burgers, you want a lot of IR.

IR is an intense form of light that glows red when it is visible to the human eye but some of it is invisible. You see it every morning from the coils inside your toaster. On a grill, IR is energy emitted by glowing coals or flames. This energy arrives at the speed of light and carries a real punch. That’s why food browns and cooks much faster when exposed to IR. IR is a great way to get a sear on your steak.

Because IR packs such a wallop, the surface of the food can burn before the interior cooks, so IR must be used judiciously, usually just to brown the surface. This is where a lot of newbies go wrong. They put the food directly over hot coals or gas burners and when the exteriors are really dark or starting to burn they take the meat off. But it is often raw in the center.

Low & slow

This we know: Heat causes muscle fibers to shrink and squeeze out juice. Heat also causes water to evaporate. It converts connective tissue to gelatin. It renders fat. I catalyzes chemical reactions like the Maillard reaction. It activates and deactivates enzymes. And it kills bacteria. So we have learned that cooking many things low and slow results in better outcomes. Throw a slab of pork spare ribs on a hot grill and you’ll get a tasty meal but it will be as ornery as Clint Eastwood. But cook them at about 225°F for 5 to 6 hours and they will be tender as a baby’s bottom and as juicy as an Agatha Christie mystery. Low and slow is the motto if you are cooking tough cuts even if they are cooked to 203°F.

[Meathead]

As an example: You wouldn't try to sear a steak in your indoor oven because hot air can't do it. But you can broil it indoors because you are using direct IR from flame overhead.

[Meathead]

More from the manuscript: Cooks often talk about heat and temperature interchangeably, but, although they are married by the kinetic theory, they are different. It is helpful to think of heat as one of many forms of energy and temperature as a measure of how hot or cold something is as a result of that energy. The more energy absorbed by something, the faster the atoms in that something move. The faster they move the higher the temperature of that thing gets.

Do this experiment: Go set your indoor oven to 225°F. Stick your arm in there. You can actually hold your arm in 225°F air for a few moments. Now press your hand against the metal side of the oven. When you get back from the hospital you will understand that, although the air and metal were both a temperature of 225°F, the heat, the energy, in the two is different. The metal stores and transmits 50 times as much energy as air because the metal has more molecules per square inch than air.

Energy melts fats, liquefies collagen, browns proteins and sugars, thins liquids like honey, dries out surfaces, crisps poultry skins, transforms solids to liquids and liquids to gases, creates vapors that smell seductive, makes air and other things expand, and perhaps most important, it kills bacteria.

When you heat food the water molecules on the surface get excited, heat up and start shaking their booty, they get the molecules next to them excited and shaking, and they get the ones next to them excited, and slowly, the energy works its way to the center of the food. That’s how the outside of the meat cooks the inside of the meat.

Energy inside the food can only move as fast as one atom can impact its neighbor, and then its neighbor’s neighbor so it can take time, perhaps even hours, to get the chemistry altered to the level we want it. We call that dinner time. Since the process is slow, energy tends to build up in the surface. That’s why so many steaks have a dark brown crust, a brown layer just below the surface, a tan layer below that, a pink layer below that, and finally, a layer of rosy medium rare in the center. Half the steak is overcooked. That’s because the energy moves slowly to the center overcooking as it goes. I call this the rainbow effect, a problem that I will show you how to avoid later when we dive into the reverse sear.

[Meathead]

Still more. You can’t measure infrared from glowing coals or gas jets with a normal thermometer. For that you need a special device like a special thermocouple into the heat source or a spectrophotometer pointed at it. And because of the inverse square law the energy dissipates rapidly over distance. And IR is often measured in watts per square meter, not degrees Fahrenheit or Celsius.

When I want you to cook with direct IR energy I’ll use a scale I made up rather than watts: The Warp Scale. Warp 10 is maximum IR on your grill, “Give ’er all she’s got, Scottie.” On occasion I may ask you to dial it back to Warp 7 or something like that when I am afraid Warp 10 is too harsh.