Boire du petit-lait

This is part of a series on French idiomatic expressions that relate to food. Read the introductory Edible Idiom post, and browse the list of French idioms featured so far.

This week’s expression is, “Boire du petit-lait” (sometimes appearing as “Boire son petit-lait”).

The literal translation is, “drinking whey” (sometimes appearing as “drinking one’s whey”) and it means basking in praise or flattery, or taking obvious pleasure in a situation that has turned out to one’s advantage.

Example: “Les invités s’accordèrent à dire que c’était la meilleure blanquette qu’ils aient jamais mangée. Derrière son sourire modeste, la maîtresse de maison buvait du petit-lait.” “The guests agreed it was the best veal blanquette they’d ever had; underneath her humble smile, the hostess was drinking whey.”

Listen to the idiom and example read aloud:

According to these sources, the expression started out in the 16th century as Avaler doux comme lait (swallowing soft as milk). It became boire du lait (drinking milk) in the mid-19th century, and the milk became whey (the literal translation of petit lait is “small milk”) in the mid-20th century.

The older expressions likely allude to the rapture with which a baby drinks milk, while the modern usage refers to the fact that whey, a nutritious by-product of cheese-making, used to be considered a treat. It is now, I am told, fed to pigs, which reminds me of another expression, c’est de la confiture pour les cochons (it is jam for pigs, the French version of pearls for swine), but I digress.

Before we part, I should note that this week’s idiom is not to be confused with its close cousin, “Ça se boit comme du petit-lait” (it drinks like whey). This one is equivalent to the English expression, “it drinks like water,” meaning that an alcoholic beverage is very easy to drink; it is usually implied that said beverage is, therefore, a little treacherous. Example: “Il faut que je me méfie, ce punch se boit comme du petit-lait.” “I should be careful, this fruit punch drinks like whey.”

  • How interesting! I don’t think I even knew what whey was! It’s funny to look at these expressions and try to figure out where they come from. Makes me want to think about American expressions – there are so many I say without even giving it a thought!

  • J’aime bien prendre des leçons de français en anglais! Bonne fin de semaine..

  • I’m loving this series Clotilde! My French is serviceable but rudimentary — and idioms are so mysterious — thanks!

  • Thanks so much for these edible idiom posts, they’re lovely.
    I think idioms are very insightful and a very colourful way of learning the spirit behind a language.
    Most interesting thing is that even though no two languages have the same idiom, they always seem to have idioms for the same thing, like ‘not my ballgame’ / ‘not my onions’ / ‘not my beer’ in English / French / German respectively.

  • Absolutely fascinating! It’s so interesting looking at where expressions came from – what a great series. I’ll have to try and add them to my French vocab.

  • It’s also a little like the English saying – The cat that got the cream, as in:

    Someone was so pleased with himself that he looked like the cat that got the cream.

    Being a lover of both French and the way language is used… I LOVE these!

  • Dawn in CA

    I love, Love, LOVE this series of posts! Decades ago, I was nearly fluent in French and Italian. Twenty+ years (and almost no practice) later…poof! It’s gone. I keep promising myself that one day I’ll begin anew my language studies. Until that day, I will enjoy these tidbits of francais from you. :)

  • Charlotte

    … and if you don’t speak any French at all, it helps to understand the transition from “milk” to “whey” to know that “whey” literally translates as “little milk” in French :)

  • Very interesting! It’s always useful to know where sayings come from. And the idiom sounds so much better in French. “Drinking whey” doesn’t sound very sexy in English. :)

  • Luke

    look at the interest in french language you inspire! a true teacher!

    enough exclamation points, i’m glad you decided to undertake this. it’s a good lesson for those of us who are still trying to master french.

  • I love this series! If you are taking any requests, will you please explain why mon petit chou, chou is so endearing???

  • Joséphine


    Je suis une québecoise qui étudie présentement aux États-Unis.
    Je trouve d’ailleurs que tes blogs sont extra!!

    As-tu des exemples comment nous devrions utiliser cette expression dans le language de tous les jours?

  • Joséphine – Il y a un exemple dans le billet, au 4ème paragraphe.

  • Yes, “cat that got the cream” is the closest English equivalent I can think of. (Although in my mind that always also implies getting away with something a little naughty. How did that cat come by that cream, anyway?)

  • J’aime beaucoup cette section de ton blog! J’apprend quelque chose en plus en français et en anglais :)

  • DF

    Thank you for all you do for your readers.

    I’d like to know whether French speakers today use this idiom, since in the example you give the passe simple and the pluperfect subjunctive are used– grammatical constructions in French which are no longer conversational.

  • DF – Yes, this idiom is also used in conversation by French speakers of today. We might for instance say, pointing to a friend who’s being praised, or a politician on television who’s just had his policy approved, “Regarde-le, il boit du petit-lait !”

  • Tarfman

    Unbeknownst to most, the word “whey” actually does come from « boire du petit lait », because when one “drinks little milk”, he or she goes, « Ouaiiiiiiiiiiiiiis ! », hence the word “whey”.

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