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

I sometimes produce labels for products. Sometimes you can wing it and use existing values. Sometimes you have to say to food manufacturers to send them to labs.
I’ve done all the labs to extract fat from food and various other nutrients. It’s great fun chemistry