Q: In your discussion of “the proof is in the pudding,” you seem to have missed the pun. Puddings, as in doughs, etc., require proofing before baking.
A: Sorry to disappoint you, but there are several problems with your suggestion.
First of all, the word “proof” in bread baking means to make dough rise by means of yeast. And yeast is not normally an ingredient in puddings—even ones that are baked.
Second, that old proverb—“The proof of the pudding is in the eating”—dates from the early 1600s, as we wrote in our 2012 post. There, “proof” is a noun meaning something like a test. But “proof” in the culinary sense, a verb, wasn’t recorded until the second half of the 19th century, according to the Oxford English Dictionary.
And third, “pudding,” a word dating from the Middle English of the late 13th century, originally meant a kind of sausage—that is, an animal’s stomach or intestine, stuffed with various ingredients and boiled.
This sense of “pudding” survived into the late 19th century, as we wrote in a 2016 post (even today, the Scottish dish haggis is sometimes referred to as a “pudding”). So the “proof of the pudding” proverb was probably about sausage.
Over time, of course, “pudding” was also used for other sorts of savory and sweet dishes. But it wasn’t until the late 19th and early 20th centuries that it arrived at its most common meanings in American and British English today.
In the US, it means a sweet dessert of a custard-like consistency, a sense first recorded in the 1890s.
In the UK, it means any sweet dessert, a usage first recorded in the 1930s. An unsweetened exception is Yorkshire pudding, a dumpling-like side dish made of batter (not dough), and no yeast.
So if puddings aren’t made with yeast, what does “proof” mean in the old proverb? Well, it’s not about baking.
As the OED explains, the noun as used in the proverb originally meant a “test” but is “now sometimes understood” to mean “evidence.” And “the proof of the pudding”—a popular phrase derived from the longer proverb—means “that which puts something to the test or (in later use) proves a fact or statement.”
As we mentioned earlier, the kitchen use of “proof” is much more recent than the proverb. This baking term (as in “to proof dough”) appeared in the 1870s, a couple of decades after a similar use of “prove” (as in “the dough proved quickly”).
“Proof” here is a transitive verb (one requiring an object) while “prove” is an intransitive verb (one that doesn’t require an object).
The OED defines “prove” in the baking sense this way: “Of bread or dough: to become aerated by the fermentation of yeast prior to baking; to rise. Occasionally also of yeast: to cause such aeration.”
Here’s Oxford’s earliest example: “The whole of the flour is … left about an hour … to prove” (from Charles Tomlinson’s Cyclopædia of Useful Arts, 1852).
The OED defines “proof” in this sense as “to aerate (dough) by the action of yeast before baking.” This is the dictionary’s first example:
“After this laborious process the finished dough is covered over for some time … during which fermentation again begins, and the mass is ‘proofed’ ” (Encyclopædia Britannica, 9th edition, Edinburgh, 1875).
Those early examples of “prove” and “proof” in baking were probably printed in italics and quotation marks because the usages were unfamiliar to 19th-century readers.
To conclude, when that old proverb appeared there was no pun intended.