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Food Writer & Recipe Developer at Food52
What's the recipe? (Usually yes, but it does depend.)
Among the things it depends on is how the author is using the word- shortening is strictly speaking any fat that is used to (surprise) shorten the cake or pastry, but is often used nowadays to mean the Crisco product. If it's in a book, it's always a good idea to read the "ingredients" section at the beginning of the book. If it's in a newspaper or online, you're likely on your own. At any rate the main functional differences between butter and Crisco would be meting temperature and moisture content, neither of which is likely to make a big difference in a cake.
Thank you. It was just a recipe I cut out of something. I did use just butter but it almost doubled the cooking time.
I'd like to hear the opinions of some other bakers, but I would say that it's virtually impossible that the substitution was the reason for that discrepancy. Hope your cake came out well, anyway.
shortening is 100% fat, butter is about 80% fat and 20% water. So yes you can use butter but you need to adjust the recipe.
20% is a legal maximum; most of the stuff you actually buy is more likely to be in the 16%-17% range; still a bit much to ignore.