A hard cheese is made by warming milk to 86-90°F, adding culture and then rennet, cutting the set curd into 3/8 inch cubes, cooking it to 102°F over 30 minutes and holding it there for 30 more, milling, salting and pressing it under 10 lb for 1 hour, 20 lb for 12 hours and 40 lb for 24 hours. The drier the curd you press, the harder the cheese and the longer it keeps, which can reach 1-3 years.
Part of Dairy Production at Scale
Semi-hard and hard cheeses are rennet cheeses whose curd is cooked, drained and pressed to a controlled moisture level, then aged in a cool, humid cave.
Moisture Is The Control, And Four Steps Set It
A hard cheese keeps because it is dry, salty and acid. You set how dry at four points: how small you cut the curd, how hot you cook it, how long you hold it, and how hard you press. Smaller cubes, a hotter cook and a longer hold all drive out more whey. Cheese Basics states the rule: a higher cook temperature gives a drier, harder cheese that lasts longer.
What You Need
- At least 5 gallons of pasteurized milk (see Pasteurization Methods)
- Mesophilic culture or cultured buttermilk (see Cultures and acidification)
- Rennet (see Rennet sourcing and preparation)
- A water-jacketed vat, a long knife, a thermometer, a mold lined with cheesecloth, a press and weights
- Salt, a cheese cave for aging (see Cheese Cave Construction) and wax or oil for the rind
Method
Step 1: Warm the milk to 86-90°F and add culture. The parent article suggests 1/4 cup of cultured buttermilk per gallon if you have no commercial culture. Ripen 30-60 minutes.
Step 2: Add rennet and stop stirring. The parent article gives 1/4 teaspoon of liquid rennet per 2 gallons, stirred for 1 minute, then left absolutely still. The curd is ready at 45-60 minutes when it breaks cleanly like soft tofu. A break that is not clean means it needs longer.
Step 3: Cut to 3/8 inch cubes. Use a long knife in two directions, then across. Pieces of unequal size cook unevenly.
Step 4: Cook slowly to 102°F over 30 minutes. Stir gently. Heating too fast hardens the outside of each cube and traps whey inside.
Step 5: Hold at 102°F for 30 minutes, stirring now and then.
Step 6: Drain the whey (see Whey utilization (pigs, gardens)), then mill the curd into walnut-sized pieces and mix in 2-3 tablespoons of salt per 5 gallons of original milk.
Step 7: Pack and press. Pack the curd into a cloth-lined mold. The parent article’s schedule is 10 lb for 1 hour, 20 lb for 12 hours and 40 lb for 24 hours. Higher pressure at the start squeezes the surface shut before the interior has drained, so start light.
Step 8: Air-dry for 2-3 days, turning twice daily, until a rind forms. Then wax or oil the rind and move the cheese to the cave.
Worked Example: Time, Pressure And Salt
- Hands-on time before milling: ripening 30-60 min + setting 45-60 min + raising temperature 30 min + holding 30 min = 135-180 minutes, or 2 hours 15 minutes to 3 hours.
- Pressure on the curd: weights in pounds are forces, so divide by the mold’s area. A 6 inch diameter mold has area π × 3² = 28.3 in². Under 40 lb that is 40 ÷ 28.3 = 1.4 psi, about 9.7 kPa. At 10 lb it is 0.35 psi. The mold diameter is an assumption; a narrower mold at the same weight presses harder.
- Salt as a fraction of the cheese: 2-3 tablespoons per 5 gallons. At roughly 17 g per tablespoon of coarse salt (a figure from memory, not from this wiki) that is 34-51 g. A common rule of thumb for hard cheese is about 1 pound of cheese per gallon of milk, so 5 gallons gives about 5 pounds, or 2.3 kg, and salt is 34 ÷ 2,300 to 51 ÷ 2,300 = about 1.5-2.2% by weight, which sits where hard cheeses normally are. Both the rule of thumb and the salt spoon weight are flagged, because the batch you actually make will differ.
Failure Modes
| Symptom | Likely cause | Response |
|---|---|---|
| Curd will not set | Rennet too weak, milk too cold, or milk overheated | Test rennet on a cup first; see Cheese Basics |
| Gas holes and bloating | Gas-forming bacteria from dirty milk | Better milking hygiene and pasteurization |
| Cracked, dry rind | Dried too fast in dry air | Raise cave humidity or oil the rind |
| Wet, soft, sour cheese | Too little cook or pressing, or too much acid | Cook longer; press harder |
| Mold on the rind | Normal at the surface | Wipe with salted water or vinegar, then re-coat |
| Cheese bitter | Too much rennet | Reduce dose |
Safety
Raw-milk cheese, hot wax and falling weights
Cheese made from unpasteurized milk can carry the tuberculosis, brucellosis and listeria of raw milk, and aging reduces but does not guarantee removal of them; pasteurize unless the herd is verified. Melted wax ignites; heat it in a double boiler away from open flame. A 40 lb press weight on an unstable frame can crush a hand.
What’s Next
- Learn next: Temperature and humidity requirements — the aging conditions
- Combine with: Cheese Cave Construction — the place to age it