Lu Dan (Master Stock Eggs)
The Chinese master stock (lu shui, the 'old lu') and the eggs that ride in it. The stock is Teochew/Chaoshan in origin, traceable to the mid-Qing, and it is never thrown away - strained, boiled, cooled, and reused indefinitely. The egg is the cheapest possible way to buy into an expensive stock: it costs nothing to add and it absorbs everything the goose and pork put in there.
The Chinese master stock (lu shui, the ‘old lu’) and the eggs that ride in it. The stock is Teochew/Chaoshan in origin, traceable to the mid-Qing, and it is never thrown away - strained, boiled, cooled, and reused indefinitely. The egg is the cheapest possible way to buy into an expensive stock: it costs nothing to add and it absorbs everything the goose and pork put in there.
Ingredients
- 8 eggs, hard-boiled and peeled (use eggs at least a week old - see notes)
- The master stock (lu shui)
- 1.5 litres water
- 150 ml light soy sauce
- 60 ml dark soy sauce (for colour)
- 60 g yellow rock sugar
- 80 ml Shaoxing wine
- 3 star anise
- 1 cassia/cinnamon stick
- 4 cloves
- 1 tsp fennel seed
- 2 slices dried licorice root (optional but traditional)
- 1 piece dried tangerine peel
- 3 slices ginger
- 2 spring onions
- 1 tsp salt, to taste
Directions
Key ingredients
Cinnamon · Rock Sugar · Soy Sauce
- Build the stock. Combine everything except the eggs in a pot. Bring to a boil, then reduce and simmer gently for 30-40 minutes so the aromatics give everything they have.
- Taste and correct. It should be markedly salty and slightly sweet - the eggs will dilute it and take some away.
- Add the peeled eggs. Simmer very gently for 15-20 minutes, then turn off the heat and let them steep in the warm stock for at least 2 hours, or overnight in the fridge.
- Serve at room temperature or cold, whole or halved, with a spoonful of the stock.
- Keep the stock. Strain out the solids. Boil it, cool it, refrigerate or freeze it. Next time: top up the water, soy, sugar and wine, refresh the aromatics, and go again.
Notes
The egg is a bystander
Lu shui is built for goose, duck, pork and tofu. The egg just rides along. That is exactly why lu dan are everywhere in China and Taiwan - they are the cheapest possible way to buy into an expensive stock.
About the ‘hundred-year master stock’
Generation-to-generation family stocks are real. VERIFIED AGES ARE NOT - every ‘100 years’ / ‘300 years’ claim I found is hedged by its own author (‘legend has it’, ‘according to hearsay’), with no named provenance. And Chinese popular press gives the game away: 百年老卤水三百万都不卖 - a hundred-year lu shui, wouldn’t sell it for three million. These are marketing assets.
The honest framing is better anyway: a master stock is not a preserved object, it is a continuously replaced one. Every cycle you lose liquid to the food and to evaporation and replace it. After a few years essentially no original molecule remains. What persists is the culture of maintenance and the recipe of replenishment - a hundred-year practice, not a hundred-year liquid.
The measurement that ends the argument
Nitrite in aged lu shui: 3-month stock = 0.64 mg/kg; 5-year stock = 1.87 mg/kg. Twenty times the age, three times the nitrite - strongly sub-linear, approaching steady state.
That cuts both ways. It means an old stock is NOT a toxin accumulator (reassuring). It also means a 100-year stock cannot taste meaningfully different from a 5-year stock. You cannot claim infinite flavour concentration and deny infinite nitrite accumulation - it is the same mass balance. Pick one. The evidence says neither.
Safety
Boil the stock before and after each use, cool it fast, and keep it refrigerated or frozen between uses. A master stock is safe because it is boiled and stored properly, not because it is old.
Peeling
Use eggs at least a week old. Albumen pH rises from ~7.6 to ~9.2 as CO2 escapes through the shell, and above pH 8.9 eggs peel easily. This is proven causally - put old eggs back under CO2 and they become hard to peel again. Fresh eggs are the worst possible eggs for this job.