Uncertain about the liters for dry ingredients

I very much would like to try this recipe as my family is a fan of both buckwheat & chocolate and the two ingredients seems to complement each other. However, I’m a bit confused in regard to the measurements. (And it must be just me as there is a review with no questions about this).
300 milliliters of chopped dark chocolate, 240 milliliters buckwheat flour, 180 milliliters sugar etc. My understanding of measurements in litres is for liquid ingredients. Can I ask for clarification or confirmation please? Thanks and have a great day!

Craggle-Top Buckwheat Brownies
Recipe question for: Craggle-Top Buckwheat Brownies


702551 November 28, 2022
It's risky to assume that one liter = one kilogram for all ingredients as they have different specific gravities. The one liter = one kilogram conversion is applicable to water.

For example, oil has a different specific gravity than water which is why it floats on top. Thus, one liter of oil is less than 1000 grams.

Even when comparing two forms of an ingredient where the specific gravity is the same, the structure of the ingredient will influence the conversion. A liter (or cup) of spinach leaves won't weigh the same as the same volume of water or sugar.

One well known example is the different between table salt and kosher salt. Due to the flaky crystal structure of the latter, one volumetric measure of kosher salt is less salty than the same measure of table salt. The most accurate way to get the same amount of saltiness is to weigh (use mass-based measurements).

It is unfortunate that this recipe author chose to use non-standard metric volumetric measurements for solid ingredients which makes zero sense.

My suggestion is to use a glass measuring cup with metric markings and follow the author's instructions but also to weigh the resulting amounts and note them for future reference.

Best of luck.
Lori T. November 28, 2022
I'm not sure how the recipe author went choosing the measures, but you are correct. As a rule, liters are used as measures of liquid volume, while the kilo- or gram is used to determine weights for dry ingredients. However, the metric system is lovely that way. 1 liter = 1000 grams. So you could simply put in grams in place of the milliliter measurements in the recipe, which helps it make better sense. I hope this will help you.
Lint_Julep November 28, 2022
Thanks for the information. I had no idea!
With the price of groceries lately I just didn't want to take a chance of it not turning out.
Thank you very much for the quick reply and information : )
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