How to Measure Solid Fat with a Measuring Cup

Measuring solid fat by volume is harder than measuring a dry ingredient. Butter straight from the refrigerator is in hard pieces, and when placed in a cup the pieces press against each other, leaving irregular gaps between them; the size of the gaps changes each time depending on the shape of the pieces. The cup looks full, but the amount of fat inside is uncertain. Softening and pressing it reduces the gaps, and melting it makes them disappear entirely; that means the same fat in three forms gives three different volumes. For this reason, solid fat is one of the ingredients least suited to volume measurement.

That is why a scale is always the first choice. When solid fat is weighed, the shape of the pieces, the temperature, and the gaps between them make no difference; a gram is a gram. The reference measurement equivalents list 195 grams for one 200 ml measure of butter and 15 grams for one tablespoon (15 ml), and these figures are enough to convert a recipe from volume to weight. If a recipe gives the amount in water-glass measures, convert it once and write the amount in grams beside the recipe; after that, do not use volume again. This conversion, done once, remains valid for every later use of the recipe.

If you do not have a scale, use water displacement; surprisingly, it is precise. Pour a known amount of cold water into the measuring cup, for example, half of a 200 ml measure. Submerge the pieces of fat in the water and press them down so they remain completely under the water. The water level rises, and the increase equals the volume of the fat. If the recipe calls for half of a 200 ml measure of fat, add fat until the water level rises by half of that measure. Then pour off the water, leaving the measured fat behind. The method also works with frozen fat, as long as the pieces fit in the container.

The method has two small rules. The water must be cold; warm water softens the surface of the fat and makes it stick to the container. The fat must remain completely under the water, because a floating piece does not displace its full volume and the measurement comes out short. When these two rules are followed, the method is noticeably more consistent than pressing solid fat into a cup to measure it, and it does not depend at all on the shape of the pieces. That is also why you read the container’s measurement lines at eye level with it on a level surface.

Keeping the container wet has a separate benefit that often goes unnoticed. Butter placed in a dry cup sticks to its surface, and some remains inside when it is emptied; the measured amount and the amount that goes into the recipe no longer match. In the water displacement method, the container is already wet, so the fat comes out cleanly and none is lost. The same trick works with other sticky ingredients; wetting or greasing the container first helps ensure that all of the measured amount goes into the recipe. This small preparation makes the measurement accurate in the pot, not just on paper.