Conversions

We're almost at the end of this pathway now. But there's one more thing we need to learn. It's not an essential part of the science of cooking – but it's definitely a good thing to know.

While following recipes, in books or online, you've probably noticed that they often use different units of measurement. One recipe might tell you to use '10 ounces of flour', while another one says '50 grams'.

This is because different parts of the world use different measuring systems. The most obvious examples are the imperial system (ounces) which is mainly used in the US, and the metric system (grams) which is used in places like Europe.

You can obviously convert between different units just by asking the internet for help. But wouldn't it be nice if you could convert them in your head instead?

Today, we'll be learning some simple conversions between different units of weight.

First of all: in a metric weight system, 1000 grams = 1 kilogram. In an imperial weight system, 16 ounces = 1 pound. By the way, ounce is often abbreviated to 'oz', while pound is abbreviated to 'lb'.

When converting between these two systems, 28 grams = 1 ounce, and 0.45 kilograms = 1 pound.

To confuse things slightly, an ounce isn't always a unit of weight. It can actually be used as a unit of volume too.

Officially, we call them weight ounces (for weight) and fluid ounces (for volume). If you're interested, 16 fluid ounces = 1 liquid pint (pt.), just as 16 weight ounces = 1 pound.

A recipe will usually distinguish between the two. If you see '1 oz' it's a weight ounce, while '1 fl oz' is a fluid ounce. But it's something to watch out for, just to make sure you don't end up with the wrong amounts.

Last time, we learned some conversions for different units of weight. This time, we'll be doing the same thing for volume and temperatures.

Let's start with units of volume, which are mainly used to measure liquids. There are three systems to be aware of: imperial (fluid ounces), metric (milliliters) and finally, cups and spoons.

First of all, 28 milliliters = 1 fluid ounce (give or take). Helpfully, as we learned about last time, there are also 28 grams in 1 weight ounce.

As for cups and spoons, 3 teaspoons = 1 tablespoon, and 16 tablespoons = 1 cup. Meanwhile, if you're converting between milliliters and cups, 1 cup = 240 milliliters.

So, we've learned some conversions for weights and volumes. But how about units of temperature?

This is actually a lot more complicated. To convert between fahrenheit (imperial) and celsius (metric) you'll need to take the fahrenheit value, subtract 32, multiply by 5, then divide by 9.

We won't ask you to memorize all that though. Instead, let's just give you a single conversion to bear in mind: the boiling point of water. In the imperial system, that's 212°F. In the metric system, that's 100°C.

We realise that all these measuring units aren't the most interesting topic. But hopefully the rest of this pathway has been interesting – because guess what? You've reached the end!

All that's really left for you to do is to put all this theory into practice. Heat chemistry, flavor chemistry, ingredient chemistry, presentation... you have so much fundamental knowledge now, which should help your cooking to reach new heights.

Find some good recipe books, and start trying things out. Or get creative, and design some recipes of your own. It's time to make some great-tasting food.

For further reading on any of this, we highly recommend Samin Nosrat's Salt, Fat, Acid, Heat, or Stuart Farrimond's The Science of Cooking.