Both sauces take their name from the Périgord region of southwestern France — the Dordogne, the epicentre of French black truffle production. Périgueux is the regional capital. The sauces were the prestige preparations of the grand 19th-century French restaurant — served over tournedos, veal medallions, truffle-studded foie gras, and the luxury preparations of the classical menu.
A Madeira-enriched demi-glace finished with diced or sliced black truffle — the most luxurious of the classical compound brown sauces, and the most expensive per tablespoon of anything in the classical repertoire. Sauce Périgueux uses truffle dice; sauce Périgordine uses whole truffle slices for more dramatic visual impact. Both depend on the quality of the truffle absolutely: a good demi-glace with poor truffle produces a good brown sauce with a slight earthiness. A good demi-glace with genuine Périgord black truffle (Tuber melanosporum) produces a sauce of almost incomprehensible complexity.
Truffle's aromatic chemistry is the most studied and least replicated in the flavour sciences — its 50+ identified volatile compounds include unique sulphur-containing molecules that do not appear elsewhere in the food world. As Segnit notes, the traditional pairing of truffle and egg (omelette aux truffes, scrambled eggs with truffle) is not merely traditional — the egg's sulphur compounds and the truffle's sulphur volatiles share structural similarities that produce mutual amplification on the palate. Madeira and truffle is equally logical: Madeira's oxidative ageing produces lactone and aldehyde compounds that provide a fat-soluble aromatic framework into which the truffle's volatile compounds dissolve and are stabilised, delaying their volatilisation and prolonging the flavour experience.
**Ingredient precision:** - Truffle: Tuber melanosporum (Périgord black truffle) — fresh in season (December–March) for the most profound result; alternatively, preserved truffle (in Madeira or juice) or high-quality jarred truffle slices. There is no culinary substitute that achieves the same result. The characteristic diamethyl sulphide and bis(methylthio)methane aromatic compounds of black truffle are unique in the flavour world. The truffle must be genuinely fragrant — smell it before buying. - Madeira: specifically Sercial (dry) or Bual (medium) Madeira — not cooking Madeira, which is salted and lacks the oxidative aromatic complexity that makes Madeira the correct wine for the truffle's sulphur-compound amplification. - Demi-glace: genuine (Entry 8). This sauce cannot be built on a commercial foundation. - Quantity: the truffle is not a garnish — it is the dominant flavour of the sauce. 20–30g of truffle per serving is the traditional quantity. 1. Reduce Madeira by half with a finely diced shallot. 2. Add the demi-glace. Simmer together for 5 minutes. 3. Strain through a fine sieve. 4. Off heat: add the diced or sliced truffle. Do not cook the truffle in the sauce at this point — heat drives off its most volatile aromatic compounds. Instead: infuse. Cover and allow the truffle to steep in the warm (but not boiling) sauce for 5 minutes before service. 5. Mount with cold butter. 6. Serve immediately — the truffle's aromatic compounds are volatile and begin to dissipate from the moment the sauce is made. Decisive moment: Adding the truffle off heat and infusing rather than cooking. Black truffle's primary aromatic compounds are extraordinarily volatile — particularly dimethyl sulphide and the sulphur-containing bis-compounds that are the source of its characteristic deep, funky, intensely earthy smell. These compounds dissolve most efficiently into warm fat (the butter in the mounted sauce) and are driven off rapidly by boiling temperatures. The infusion method — truffle in a warm but not boiling sauce — extracts the maximum aromatic compound into the sauce's fat phase without volatilising the most delicate components. Sensory tests: **Smell — the truffle addition:** The moment fresh truffle is added to the warm sauce: an immediate and dramatic aromatic transformation — the volatile sulphur compounds of the truffle begin to dissolve into the sauce's fat phase and the smell of the sauce shifts from Madeira-and-demi-glace to something more profound and complex. If no aromatic shift is perceptible, the truffle is of poor quality or past its peak. **Taste — the finished sauce:** The four notes of sauce Périgueux: the oxidative, nutty-dried-fruit depth of the Madeira; the savoury, gelatinous richness of the demi-glace; the cold butter's lactic smoothness; and the truffle's ineffable depth — simultaneously earthy, funky, sweet, and mineral. No single note should dominate. Service must immediately follow preparation.
- A truffle stock — made by simmering truffle skins and trimmings in a light veal stock — can substitute for regular stock in the demi-glace base and produces a sauce of remarkable truffle depth even with less whole truffle in the finish - The sauce can be made with preserved truffle (truffle in Madeira from a jar) — the cooking liquid from the jar is added with the demi-glace for an additional layer of truffle flavour - For an intensely economical use of truffle: store the truffle wrapped in a cloth inside a container with 4 eggs. Over 48 hours, the truffle's volatile compounds penetrate the eggs' shells — truffle eggs, cooked any way, at approximately 2% of the cost of a truffle portion
— **Truffle flavour minimal or absent:** Either the truffle was of poor quality, the truffle was cooked rather than infused (the volatile compounds were driven off), or too little truffle was used. Generosity is the only approach with truffle — 20g per serving is correct. — **Sauce does not taste of Madeira:** The Madeira was not reduced sufficiently before the demi-glace was added — its aromatic compounds need to be concentrated through reduction to survive the addition of a rich base.
Jacques Pépin's Complete Techniques