Oh hi! My name is Heidi and I want barbeque (BBQ). Um, I mean I want to talk about the
science of BBQ. Welcome to Sizzling Science. In one form or
another, BBQ has probably been around since people were able to control fire.
Humans likely figured out very early on that meat cooked over an open flame is, well, let's
face it, wildly delicious. In this video, I want to explore this tasty
cooking method and gice you some safely tips as well.Fair warning vegetarians and vegans,
I will talk about fruit and vegetables, but this is primarily about the science of cooking
meat. Humans are hard wired to get pleasure out
of complex aromatic foods and BBQ delivers big time.Let's focus on 3 reasons for that:
the cooking, the seasoning and the smoke. Let's start with cooking.The reason meat can
be tough or tender is that it is primarily made of muscle. Muscle is almost exclusively
protein and water. When it is raw, it is a set of microscopic, tightly bundled strands,
holding on to quite a bit of moisture. Some muscles work less hard than others.For example,
the meat near the spine of a cow does not get nearly as much of a workout as the shoulder.
So it is going to be softer with a less dense network of strands. When we heat that protein
up, it unwinds and loosens, and the meat usually becomes more tender...to a point. Too much
heat for too long a time can lead to denaturation of the protein or a further breakdown of the
strands and a loss of moisture and fat, which can lead to toughness and dryness.
So part of the art of BBQing is figuring out the best method of cooking. In the case of
a tough cut of meat, the heat can soften the connective tissue, a different type of protein,
like the collagen in ligaments. This can take a long time, so to compensate for a potential
loss of moisture and toughening of the muscle protein, it is cooked at a lower temperature
under cover with indirect heat and often water is added. That low, slow, moist, covered cooking
on a grill is what chefs call 'BBQ'. What chefs call 'grilling' is different, believe
it or not. Grilling is usually done quickly over direct heat so there is less moisture
loss because the meat is usually more tender in the fist place, it does not need the extra
cooking time to loosen up the muscle strands.So low and slow BBQ is great for cooking larger
cuts of meat, like a whole chicken or a rump roast. Grilling is great for quickly cooking
smaller portions of meat, like a chicken leg or a sirloin steak.
The cooking also leads to something called the Maillard Reaction, named after the French
scientist who discovered it. It is a complex, multi-stage reaction, when heat changes amino
acids and sugars, turning them a caramel brown and releasing all sorts of great-smelling
aromatic compounds and savoury flavours. This definitely in BBQ. Muscle protein is a rich
source of amino acids, though we see this reaction in lots of other cooking, including
baking. It's the reason for a rich golden pie crust, for instance.
Since meat is lower in natural sugars, to boost the reaction in BBQ, we often add sugars
in the form of rubs or sauces. Of course, meat isn't the only thing that can be grilled.
Many fruits like pineapple or peaches rich in sugar and moistness are incredibly delicious
grilled, because of that almost magical Maillard Reaction.
Not only that but seasoning is huge in BBQ. A lot of it is personal taste, but science
plays a part too. Spices have a lot of volatile organic compounds, molecules that easily react
to air, water or fat. And along with the Maillard Reaction, they can infuse BBQ with a complicated
combination of scents. Something like vegetables, although they get tastier through the Maillard
Reaction, are still a bit bland, so adding your favourite herb and spice blend can jazz
them up quite a bit. If you grill with charcoal or wood chips,
the smoke created carries a lot of volatile organic compounds from the wood. That smoke
infuses into the cooked meat and we taste the delectable complex results.
However, fatty meat can also cause smoke, which happens when melting fat drips into
the flames, and this is where I start talking about BBQ safety. That kind of smoke, which
happens most often when you grill, contains molecules that you definitely don't want to
ingest. Burning food creates compounds called heterocyclic
amines or HCAs in the meat itself and polycyclic aromatic hydrocarbons or PAHs in the smoke.
These compounds are linked to a higher risk of certain types of cancer. The longer and
higher the heat, the worse the effects. The good news is t's not too hard to reduce the
levels of those chemicals by cooking more gently and, even tastier, by marinating. It's
a little unclear why it works, but studies have shown that soaking your meat in an acidic
marinade ahead of cooking and seasoning it with certain ingredients like rosemary, onions
or garlic, seems to help. If you do end up with some charring, cutting off the black
bits before serving also reduces the risk. Another safety consideration is fire and heat
safety, so make sure you have access to a working fire extinguisher, oven mitts and
long handled utensils to keep your hands away from the heat. Proper food handling is also
something to keep in mind. Raw or undercooked meat, especially when left unrefrigerated
or uncovered can lead to harmful levels of food poisoning bacteria. Those bacteria can
be transferred easily to other surfaces and other foods if you share utensils and things
like plates and trays, or use the same germ-laden trays when carrying the raw meat to the grill
and then off the grill and to the table. So use separate plates or trays for that task,
and make sure you store meat at the proper temperatures and cook to the recommended internal
temperature, which can vary, depending on the type and size of your portion. Investing
in an instant read probe thermometer like this one is a great idea. And don't let you
leftovers sit out at room temperature, put them in the fridge pronto.
I hope this has you fired up for some new cooking adventures and experiments. And please
post your results on our social media platforms, especially if you have a great recipe for
a BBQ sauce or a rub, I'd really love to try it. In the meantime, whether it's meat, vegetables
or fruit, happy grilling and bon appetit!