ELi5: How do they measure calories etc for nutritional labels?

Question

I always wonder how “they” can know the exact amount of fiber, protein, carbs and sugars, etc when I’m reading ingredient labels.

PS: couldn’t decide between biology or chemistry flair since I guess my question relates to biochemistry! Haha

In: 527

Answer 1

Not a full answer, but in regards to calories:

1 calorie is equivalent to the energy needed to raise the temperature of 1 gram of water by 1 degree celsius.

This is why things that are super high in sugar (like gummy bears) can not only be set on fire, but go off like a fuse putting off a ton of heat in a short period.

You can (very roughly) calculate the amount of calories in something by setting it on fire.