Question: I'm reading *The Count of Monte Cristo* at the moment and found this sentence:

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> One can't expect the son of a Girondin to be entirely free from the spice of the old leaven. 
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Answer: 
It's a very clumsy translation from the French. 

The original is "One cannot be the son of a Girondin and not preserve a *goût de terroir*". 

* A *Girondin* is literally an inhabitant of the Gironde, a region in western France; but during the Revolution (a generation before the time at which this epsisode is set) the Gironde was also a name for the most extreme republican party, many of whose members hailed from that region.
* The phrase *goût de* may be understood as either "a taste/hint of" or "a taste/appetite for".
* *Terroir* means "land, soil, earth"; but it also evokes *la terreur*, the Terror, the revolutionary excesses of the Girondins.

So in saying that Villefort's attitude is characteristic of the country his family comes from, the marquise also insinuates that he shares the attitude of the sponsors of the Terror. 

In fairness, it's almost impossible to reproduce such a cunning use of one language into another. This translator elects to reproduce the indirection, the insinuating character of the line, and bypasses the specific references. But this is so indirect that the real venom is entirely lost.
Without knowing anything about the context, it seems the sentence means something about the son (his personality most likely) has been influenced by his family. It's like an old fashion way of saying "The apple doesn't fall too far from the tree."