What is good food?

Food is essential. We couldn't live without it. But it's also an absolute joy. There are few better feelings than the burst of flavor when you bite into your favorite dish.

There's some science behind that feeling. Essentially, whenever you taste something good, it triggers your brain's reward system. In response, your brain releases dopamine, also known as the 'feel-good' hormone.

You don't only feel that hit of dopamine when you taste something extra delicious. You also feel it when the food arrives in your gut. That's a double dose of 'feel-good'. First, when you put the food in your mouth. Second, when you swallow it down.

The link between food, and your brain's reward system, isn't there by accident. Instead, it has an important evolutionary function.

Think of it like this: a prehistoric human who ate high quality food (like a sweet piece of fruit, or a hunk of meat) was more likely to survive than a prehistoric human who ate low quality food (like some twigs).

Why? Good food is a source of energy, nutrients, and vitamins. In general, that kept our ancestors healthy, and in turn, this helped them stay alive.

So our brains evolved to reward us. The bump of dopamine was a message: "Yes, this food is good for you. Find more and we'll live for longer!”

In the modern day, the evolutionary benefits of quality food aren't quite as strong as they used to be. Your long-term survival isn't at stake if you can't get your hands on something tasty.

But our brains don't seem to have realized that yet. And while they're still rewarding us for great tasting food, why don't we make the most of it? Perfectly cooked steaks... well-seasoned salads... incredible bowls of pasta.

That's where the Science of Cooking comes in. By the end of this pathway, you'll know how to make such delicious dishes that your brain will reward you every time.

When we say that this pathway will teach you how to make delicious dishes, we're not talking about learning recipes. Instead, we're talking about the fundamental principles of food.

The chemistry of heat, and salts, and acids. The science of herbs and spices. The art of making sauces, and preparing proteins, and cooking perfect carbs.

All these principles (and many more) are at the heart of amazing cooking. If you master them all, your experience with food will never be the same again.

Before learning to cook great tasting food, it's useful to know how 'tasting' actually works. It all begins with that thing between your teeth. That's right – let's talk about the tongue.

Our tongues are covered by tiny little bumps called papillae. Each of these bumps contains taste buds. These are clusters of special receptor cells, which are designed to detect different molecules, and share this info with the brain.

Our brains associate different molecules with different fundamental tastes. For example, a sugar molecule (glucose) is associated with sweetness, whereas a salt molecule (sodium chloride) is associated with saltiness.

There are five main flavors which our tongues are able to detect. We've already mentioned sweet and salty – the other three flavors are sour, bitter, and umami.

So, when our taste buds detect molecules of sugar, our brain interprets that as sweetness. When they detect molecules of salt, our brain interprets that as saltiness. As for sourness, that's our brain interpreting the presence of acid.

Bitterness is a bit more complicated. That taste is set off by a wide range of chemicals, most of which are found in plants. And last but not least, we have umami. This is what we call that savory taste that you get from a piece of meat. This taste is activated by amino acids, a type of molecule found in proteins.

It's no coincidence that our tongues have evolved to detect all these different molecules, and our brains have evolved to interpret them as different tastes.

As we talked about last time, this is basically a way to make sure we're getting the right food. Sugar molecules are a good source of energy – so when our tongue detects them, our brain makes sure they taste great. The same goes for salty and umami foods. Our bodies need plenty of salt and protein to survive.

On the other hand, bitter and sour tastes are often a sign of bad food. Most of the chemicals which activate bitterness are toxic to humans, while sourness might indicate spoiled fruit or meat. It isn't always that simple – a bitter piece of chocolate, or some sour lemonade, can actually taste amazing. But only in moderation. Our bodies shouldn't have too much.

Before we finish, let's bust a quick myth.

The tongue is often mistakenly thought to have specific zones for each different type of taste. But actually, every single part of your tongue is equally good at detecting the different tastes.

The one exception is the back of the tongue, which is definitely able to detect all the tastes, but is slightly more sensitive to bitterness.

This probably evolved as a final resort to protect us from harmful chemicals. If the back of our tongue gets a big hit of bitterness, just before we swallow, maybe we need to think twice about eating that food.

When we think about the sensory experience of food, we generally think about the tongue. But our other senses can also play a massive role in our experience. Imagine biting into a fresh apple; its smell is also part of the experience, as well as the texture, and even the sound.

Let's start by talking about smell. We can actually experience the smell of food via a couple of different channels. First, whenever you lift a piece of food to your lips, the aroma particles rising off it will naturally waft into your nostrils. Second, when you chew that food in your mouth, more aroma particles will flow up your throat, and reach your nose that way instead.

We call these two routes orthonasal olfaction (smells reaching your nose via your nostrils) and retronasal olfaction (smells reaching your nose via your throat). Together, they provide a comprehensive experience of aroma.

Last time, we saw how our tongue evolved to detect five main tastes. But our nose is a lot more sensitive; some studies have found that our aroma receptors are able to detect and differentiate between more than a trillion different scents.

In other words, while the tongue is great at detecting broad strokes, the nose is able to add to the experience by picking up tiny subtleties. This combined experience of broad strokes (taste) and subtleties (aroma) is what we often refer to as flavor.

Some experts think that aroma is actually the most important part of this pairing. Studies suggest that aroma can account for up to 80% of the flavor experience. It's why, whenever you're suffering from a cold, and your nose gets blocked up, you find that a lot of the food you eat is a lot less flavorsome than it should be.

So, we know that the taste of food, and the smell of food, combine to generate flavor. But what about other factors? For example, how does texture play a role?

As well as taste receptors, our mouth is also home to somatosensory receptors – in other words, receptors for detecting things like pressure and temperature. Together, these receptors play a role in something called mouthfeel, which is basically just the physical sensation of a piece of food in your mouth.

As a simple example, imagine the difference between a cold piece of raw carrot sitting in your mouth, compared to a hot piece of cooked carrot. Your experience of flavor (taste and aroma) might be relatively similar for both pieces of carrot, but the mouthfeel (texture and temperature) will be totally different for each one.

As well as taste, smell, and mouthfeel, sound and sight are also worth mentioning in the context of food experience. While there's not as much scientific backing for these two, it's hard to deny that the crunch of a vegetable, or the sizzle of a steak, can improve our experience of a dish.

As for the sight of food... can you honestly say that your experience of a salad would still be the same if all the leaves were dyed an ugly brown?

The color of food sets an expectation for your eating experience as a whole. Again, this is linked to evolution. When food looked bad, our ancestors could avoid it, without needing to put it in their mouths.

To sum things up: good food will always be a multisensory experience. By extension, if you want to become a good cook, you'll need to learn how to harness all these senses effectively.