Gruyère: A Washed Rind in a Cave That Is Deliberately Too Damp
Alpine wheels are washed for two reasons: to keep the surface from drying into a shell, and to seed it with the orangish bacteria that give the rind its smell and, eventually, some of the paste its flavour. The wash here is weak and frequent, which is the opposite of what a Taleggio wants.
Each segment is as wide as its share of the 122 minutes in the vat; the set segment carries the set temperature, the cut segment carries the cut size.
Salt and press drawer
Press ladder
- 10 kg1 h
- 22 kg7 h
- 35 kg12 h
2-3% brine wiped over the surface every 2-3 days. Selects for Brevibacterium linens and the orange, oniony rind.
A finer cut and a hotter cook than a semi-hard
Raw milk, 1.2% thermophilic culture at 33 C, thirty-five minutes of ripening, 24 IMCU of calf rennet per litre, thirty-five minute set. Cut to 5 mm and rest ten minutes, then heat to 54 C over forty minutes, stirring continuously.
The target moisture is 34%, and the only way to get there is the combination of a very fine cut and a long, hot cook. A 10 mm cut simply will not shed enough water, and the wheel will be soft in the middle at six months.
Press under whey for the first hour
Keep the curds under the whey at 50 C and press there for the first hour at 10 kg. Then take the wheel out, and press at 22 kg for seven hours and 35 kg for twelve.
Pressing under hot whey is an alpine habit that pays for itself: the curds knit without the surface cooling and hardening, and the wheel closes evenly instead of forming a skin that traps whey in the centre.
Twenty-two percent brine, then wash with 2%
Brine at 22% and 12 C for eighteen hours for a 3.6 kg wheel, turning once. Then dry at 14 C for two days, and move to the cave.
Wash the top and bottom faces with 2% brine every second day for three weeks, then twice a week. The rind should end up a mottled brown-grey with a fine, slightly granular texture, not a uniform orange. A uniform orange Gruyère rind means the wash was too strong.
Fourteen degrees, 90% humidity, ten months
Age at 14 C and 90% RH. On a wooden shelf, if you have one: the plank wicks moisture away from the underside and gives a much better rind than a wire rack, at the cost of turning the wheel more often. Turn daily for the first month, then twice a week.
At five months the wheel is pleasant but simple. At ten months it has the nutty, slightly sweet alpine flavour with the small crunch of crystals and a long finish. Gruyère aged past fourteen months gets very dry at the rim; rub the rim with a little lard if you intend to go that far.
Aging parameters
| Milk | Raw cow milk 3.9% fat |
|---|---|
| Culture | Thermophilic 38–45 °C |
| Rennet | Calf rennet (animal) 24 IMCU/L |
| pH at drain | 6.4 target 6.1–6.5 |
| Target moisture | 34 % |
| Cave temperature | 14 °C |
| Cave humidity | 90 % |
| Aging days | 300 days |
| Rind treatment | Brine wash |
| Yield | 3.6 kg |
Raw cow milk Hard 300 days
Defect diagnosis
Flagged on this make: Faulty eye formation、Misread surface mould、Bitterness
Bitterness seen this make
Signal — A harsh, lingering bitter note at the back of the palate, strongest in the first three weeks and often fading after six.
Cause — Too much rennet for the set time, or a microbial coagulant with high protease activity, or a scald that never got past 38 C.
Fix — Cut the dose by 20% next make and hold the scald 2 C higher for 10 minutes longer. Bitter peptides are water-soluble, so a 12% brine for 24 hours pulls some out.
Rancidity not seen
Signal — Soapy, paint-like smell that hits before the cheese reaches the mouth. Sharp and unpleasant rather than merely strong.
Cause — Free fatty acids released by lipase, usually from raw milk that sat warm too long, or from rennet paste, or from a knife or cloth that carried old milk residue.
Fix — Chill milk to 4 C within two hours of milking and pasteurise anything older than 24 hours. Retire the cloth: boil it, do not just rinse it.
Faulty eye formation seen this make
Signal — Either no eyes where the style demands them, or a scatter of irregular slits and cracks instead of round, evenly spaced holes.
Cause — Coliform or yeast contamination from unsanitary brine, or a press that was too cold (below 18 C) so the propionic culture never woke up, or too much salt killing it outright.
Fix — Boil and re-salt the brine to 18-20% between batches, press at 20-22 C for the first six hours, and keep the salt under 1.6% for eye-forming styles.
Misread surface mould seen this make
Signal — A grey-green or black fuzzy patch on a rind that was supposed to be white or orange, or blue speckling on a hard cheese.
Cause — Wild Penicillium and Cladosporium from a cave with moving air and standing humidity. Also from brushing a good rind with a damp, dirty brush.
Fix — Distinguish before you discard: white felt and orange smear are wanted, green fuzz on a hard rind is surface only and rubs off with 3% brine. Black patches that pit the paste mean the wheel is lost.
Four things to carry forward
- 1.2% thermophilic, 24 IMCU/litre, cut to 5 mm
- Press under 50 C whey for the first hour
- 22% brine for 18 hours, then wash with 2% every second day
- 14 C / 90% RH for ten months on a wooden shelf