Blame the Redcoats
The majority of us Americans, and some others, use measuring cups when baking or cooking. This means measuring by volume, or by the amount of product that can fit in a cup or some various fraction. As a result, we all have a ring of metal cups and spoons hanging somewhere in the kitchen that occasionally clink and clank like a cheap wind chime.
Prior to 1826, England used the English Units of measurements. And even then they had two different variations of that with the Winchester Units and the Exchequer Standards before that. The good thing about being an old country is that you have plenty of time to change your mind back and forth on a subject as many times as you want (just look at the number of constitutions France has had). The first was for King Henry VII, where we get the gallon and the quart. The Exchequer gave us the pound, the stone, and my favorite, a hoghead (equal to 54 gallons of ale, or 63 gallons of wine). In 1826, we received our weights and measures act in England, and America was a little too busy not liking Europe to think about adopting their new measurement systems. Therefore, we stuck to the old English system we knew and had used decades before we declared independence, and didn’t think any new ideas out of England were worth the change. Although, one could argue that the new system was… still from English. But hey, it’s better than us starting from scratch.
In short, we’re using a measurement system that is over 200 years old because we were anti-European and didn’t want to change. Now, I also have listened to the Hamilton soundtrack and realize that we had a bit of a “tiff” when it came to the English from our side of the pond, but the metric system has lots of merits.
Counselor, present your argument
We should be weighing our ingredients, not scooping and collecting them in a bowl or cup. End of story.
Why? Well, to keep things consistent.
Ingredients are flexible. If you do a quick search you can find that 8 ounces = 1 cup. That’s pretty true if you have a flat liquid. But how often are liquids flat? What if you have a soda filled with bubbles, versus a flat soda syrup. The “1 cup” for a carbonated drink versus a flat one is very different. If you made root beer cupcakes one day with a fresh soda, and another day with old soda, but measured a “cup” each time, your second batch will be very different than your first.
This same process happens with flour, baking soda, and the like. Air expands and compresses as the humidity changes with weather. Even if you measure everything correctly each time, a cup of flour will absorb liquid differently on different days because the air has a different amount of humidity. I can’t tell you how many times I have heard “It worked last time I baked it. I don’t know what’s different!”. It’s your environment that changed, and your ingredients adapted to it.
Look at this graph of flour (silently stolen from here) versus humidity. Let’s say you live in an area whose weather changes on a dime like I do, and you scoop a cup of flour. That flour could range in weight completely, but still take up the same amount of space. Because flour naturally absorbs water, it will have absorbed so much water from the air that it won’t absorb as much from your wet ingredients like eggs and milk. You wouldn’t know that your flour is “heavy” unless you weighed it instead of scooping.
And, what if shared a recipe across the pond? A teaspoon in America … is not a teaspoon in England. In America a teaspoon is 15 mL and in England? 20 mL. Bet you didn’t know that! Imagine if we brought in the Aussies as well, and then you have a third “teaspoon” to consider.
Get yourself a kitchen scale. There are plenty out there on the market, but find one that meets your budget. Measure your ingredients in grams and ounces, not in cups and teaspoons unless it’s a spice or an extract. Those are pretty dependable as far as change since they’re ground into a uniform powder. This also means that no matter what bowl or cup you use, you can measure the amount you need. No more worrying if you leave your 1/3 cup in the dishwasher and forgot about it.
Here are some suggestions for kitchen scales:
If none of my arguments or histories convince you, the one thing that most likely will is this: This is how ingredients are measured on the Great British Bake Off. I mean, that’s all you really need to know.