Oil and water are fine, but flour already starts to be a problem. How densely is it packed?
Then we go on to salt, which can have a lot of different grain sizes (although that is annoying with a scale as well because most kitchen scales are not very accurate with single-digit-grams)
Then it gets really weird when they say to use a cup of grated cheese, because depending on how you grate it it has very different densities
Well technically a hollow sphere would be best… Works best in space though