The science of hot-and-fast BBQ

The science of hot-and-fast BBQ

Previously we discussed the principles of cooking low and slow BBQ. Cooking for longer periods of time at a temperature ranging from roughly 110C/225F - 135C/275F. In that write up, we looked at the science of heat transfer and all the merits of cooking slowly to reduce the temperature gradient and get a more even cook throughout the meat, and you’d be forgiven for thinking by the end of that, “Why would you ever cook hot and fast?”

Despite all the science of low-and-slow being a superior way to cook meat, hot-and-fast is often a popular method of cooking, and in recent years hot-and-fast BBQ has grown in popularity, and become a lot more common on competitive BBQ circuits, so it’s probably right that we have a look at it.

Of course, I will preface this with my normal caveats: cook food the way you enjoy it. Whilst science can govern how energy is transferred and what happens as meat is cooked, it can’t govern your enjoyment and tastes. Likewise, maybe you have a setup that you are comfortable with and know just how to get great results - if so, don’t worry about altering that for the science, keep doing what you’re doing and keep cooking great BBQ. I’m not here to tell anyone not to cook hot-and-fast, enjoy yourself and enjoy your food, this science is just for fun.

The Ultimate Guide to Hot-and-Fast BBQ

1. What is Hot-and-Fast cooking?

As already mentioned, its cooking at higher temperatures, for shorter periods! In BBQ, if you start moving towards temperature ranges of 160C/325F then people will start to refer to it as hot-and-fast, although in the scale of things, thats right down the bottom end of the range.

As we covered previously, the higher the cooking temperature, the steeper the potential temperature gradient throughout the meat - which, by and large, is not a great thing. But of course, there are some caveats to this, with the most obvious example being a steak. Ideally the internal temperature of your steak is as even as possible, so you get that perfect, edge-to-edge level of done-ness, but the exterior you obviously want to be at a much higher temperature. If for example, you are cooking a steak to medium rare, you want edge-to-edge perfect pink meat inside, but you don’t want to see a pink exterior! No matter what temperature you like your steak cooked to, you are going to want the exterior to have a deliciously deep, reddish brown crust.

2. Is hot-and-fast a good technique for cooking steaks?

Well, it’s not quite as simple as that.

Sure, at face value it seems like our previous example where we wanted a fairly low internal temperature for our medium-rare steak and a higher exterior temperature for our nicely browned crust would be an ideal candidate for cooking hot-and-fast - after all, we have already determined that the downside of cooking hot-and-fast is a steeper temperature gradient throughout the meat. However, when we cook a steak we don’t actually want a straight forward linear gradient (a temperature gradient that is a straight line), we want something more like an exponential gradient (a graph that is flat and then suddenly goes sharply upwards - often called a hockey stick chart). That is, we want as flat a gradient as possible throughout the middle of the meat, and just at the most outer layer we want a sharp increase of temperature for our crust.

As we know, applying a constant energy source (a hot skillet, for example) will give us more of a linear gradient temperature. For example, if you heat up your skillet, chuck your steak in and cook it for 5 minutes, flip it over and cook for another 5 minutes, you might end up with just the right temperature and done-ness in the very centre of the steak, but it will be a gradient of done-ness from their outwards, and you will likely have a much more done, grey-ish band around the meat as the outer parts of the steak are cooked far beyond your target temperature.

3. So you’re saying hot-and-fast isn’t good for cooking steaks?

Nope. It is, in fact, a great method for cooking steaks, and that is for one very key reason: convenience! Well, it’s more than just convenience - its a combination of convenience and a relatively small reduction in quality.

The great thing is, you can cook an amazing steak hot-and-fast straight on a skillet, just flipping it once. Sure it might not be edge-to-edge pink inside, but if you get a nice piece of steak, salt it and cook it quickly in a pan it will taste great. It’s so easy and delicious and despite any slight over done-ness on the outer parts of the steak it will still provide a great meal in a matter of minutes. So why bother spending so much longer to cook it low-and-slow?

The same applies to lots of meat that we cook hot-and-fast (even if we don’t talk about it in these terms) - chicken breast, stir fry, whole roast chickens - all of these produce great results despite cooking hotter and faster. As you may have also worked out, the size of the piece of meat also makes a difference - smaller pieces of meat can be cooked hot and fast quite easily, because it takes less time for the energy to be transferred to the centre of the meat, so less time for the outer layers to over cook. If you have a thin piece of steak, a quick minute or so each side in a hot pan will probably result in a pretty even cook throughout, where as a bigger piece of meat that gradient will be even bigger (just think about a gradient on a graph - the further the distance on the x axis, the greater the change on the y axis will be. Maths is fun right?).

What’s more, let’s give hot-and-fast the credit it deserves - sure we keep talking up low-and-slow for its ability to achieve edge-to-edge perfection, but there is another part of the equation here that is just as important, and thats the crust! The Reverse Sear technique to cooking steaks (amongst other things) works so well precisely because it is a perfect combination of low-and-slow and hot-and-fast - It utilises low-and-slow to gently cook the inside to perfection, then uses hot-and-fast to quickly sear the outside to bring the beautiful depth of flavour and crust. Both elements are equally important here.

4. Better hot-and-fast steaks: Just Keep Flipping (JKF)

Another hot-and-fast technique that improves the performance has been popularised by Jess Pryles - you can read all the details on the technique in that link, but the basic method is, just-keep-flipping! The technique involves cooking hot-and-fast and to just keep flipping the steak over every 30 seconds or so.

So why does this work better than just cooking it on the same pan and flipping just once? It’s again down to the energy transfer. Whilst one side is on the hot pan, its getting loaded up with energy - the exterior is getting the full force of that so its doing its work drying out and forming our nice crust, and some of the energy starts getting transferred inwards, but then before its got a chance to get too much energy in on the outer layers, we flip it, completely removing the energy source from that side. This lets the energy in the outer layer, which didn’t have enough time to get too high so as to over cook the steak, slowly dissipate and transfer at a lower, and slower pace inwards to gently cook the inner parts. When it comes time to flip it again, the energy has slowly been transferred and we can blast it with another quick hit of energy.

5. BBQ and Hot-and-Fast

Ok, so hot-and-fast can be great for a variety of things - quick midweek steak dinners, burgers and the second step in a Reverse Sear. But is it any good for BBQ?

I don’t really like definitive answers on cooking, or BBQ. But I think it’s fair to say that traditional BBQ does not benefit from higher temperatures. There is of course a scale - the lower you cook, taking sous-vide as the minimum point where by you cook at the exact internal temperature you wish to reach, so physically impossible to overshoot the temps, as you increase the temp, the more you increase the risk of the outer parts of your meat overshooting the temps. But of course, the reality is, it can be perfectly fine to overshoot the temps in parts of the meat. If you cook beef short ribs, or brisket at the standard 110C/225F on your grill, then by the time the centre of that piece of meat hits around 95C/203F the outer parts are going to be higher, most likely closer to the cooking temps - but that doesn’t stop those foods coming out amazing. Likewise, I generally cook a roast chicken (when cooking indoors) as hot as my oven will go (220C) but its quick enough that if you monitor it carefully with a thermometer probe, you can get a great roast dinner pretty quickly.

From a scientific point of view - lower temperature cooks are more conducive to better results (notice the wording here - not saying you can’t get great results cooking hotter). The slower, lower temperatures are going to result in a more evenly cooked piece of meat, and what’s more, the meat benefits from the longer cook time. The breakdown of collagen (the connective tissues in short ribs, brisket, pork butt that are tough but transform to gelatin resulting in the most beautifully moist BBQ) is not just a product of temperature, but temperature and time.

It’s not that collagen/connective tissue suddenly and instantly breaks down to gelatin at 95C/203F internal temperatures, but generally speaking, by the time the meat hits those temps, it has been exposed to high enough temps for long enough that it has broken down. Experiments suggest that the transformation of collagen/connective tissue into gelatin starts as low as 60C/140F (the process does speed up as the temperature increases, but nowhere near instant at the usually stated done temp for brisket etc of 95C/203F). This is exactly the reason why brisket cooks will always recommend going by probe/feel and not temperatures when cooking brisket - if you read forums and message groups you will quickly discover people who have taken brisket off at 98C/208F and still have it tough.

My recommendation would be to experiment with higher temperatures, slowly increasing them, and seeing how the results come out. Being able to shorten the average cook time of a brisket by a couple of hours definitely sounds appealing, right?! But if you are going to go for it, then keep in mind the science and how to handle that - moving and rotating the meat throughout the cook (as in the Just Keep Flipping method), but it will be less effective if you are cooking in something like a bullet smoker or kamado (they function more like a convection oven), but still worth doing just in case there are hotspots. In an offset rotating makes more sense as there is a more definitive direct heat source from the fire. I’d also suggest making sure you wrap the meat - that will provide a highly humid atmosphere that will reduce the temperature directly heating the meat (it will use more energy to heat the liquid in the wrap, which will cook at a lower temperature but with increased energy transfer)

My point is, low-and-slow will give you more reliably evenly cooked meat, and reduced risk of any part of the meat being overcooked, but at the cost of time - what we want to do is find that balance that gives us great results ideally as conveniently as possible. Lots of people swear by hot-and-fast brisket, you don’t have to cook as low as possible to get good results, but if your cooking temperatures creep too high then parts will inevitably be overcooked, so find that balance that works for you and go for it!

Photo by iulian aghei on Unsplash