Quick Garum (Koji-Driven)

Garum is a dark, intensely glutamate-rich seasoning liquid — historically a slow fish sauce, here accelerated by koji enzymes and gentle heat. Hold a salted koji-and-protein slurry at a warm, steady 55-60 °C and the proteases liquefy it into a savory sauce in 2-6 weeks instead of a year. The same build makes peaso garum (yellow-pea), mushroom garum, and meat or shrimp-shell garums. This recipe follows the Amino Pastes method.

Ingredients

Work by weight. Salt is a percentage of the total mash (protein + koji + water). A “Jar” is a quart/litre jar or vacuum bag (~1 kg mash); a “Crock” is a 2 L vessel (~2 kg mash). The default below is a mushroom/legume garum at 10% salt.

Component	1 Jar (~1 kg mash)	1 Crock (~2 kg mash)
Protein (mushroom, cooked legume, meat/fish trim)	400 g	800 g
Rice koji (~25% of mash)	250 g	500 g
Water	250 g	500 g
Salt (10% of total mash)	100 g	200 g

Note

Salt is 10% of the total mash weight here (mash = protein + koji + water + salt-target basis). Worked simply: 400 + 250 + 250 = 900 g pre-salt; add salt to reach ~10% of the finished mash → ~100 g. Stay in the 8-12% band — animal-protein garums sit toward the higher end. The dry-salt calculator and salt converter help size it.

Yield

About 700-800 ml strained garum per Jar / ~1.5 L per Crock, plus savory pressed solids. A concentrated finishing seasoning — a little goes far.

Calculated values

• Salt %: 8-12% of total mash weight (10% default; lean to 11-12% for raw meat/fish).
• Koji load: ~20-30% of mash — the enzyme engine.
• Target finished pH: ~5.0-5.8 — above the 4.6 line. This is not an acid ferment.
• Warm-aging temperature: 55-60 °C / 131-140 °F (sous-vide bath, yogurt maker, or proofer).
• Duration: 2-6 weeks.

Info

At 55-60 °C the koji mold is dead but its enzymes are still active — you are running a controlled enzymatic digestion, not a live ferment. Safety here rests on salt plus the warm, near-pasteurizing hold, since the pH stays above 4.6. These are perishable fridge/freezer seasonings, not shelf-stable.

Readiness window

	Detail
Early	Week 1: liquefaction begins, aroma darkens and turns savory
Maturing	Weeks 2-4: solids dissolving, liquid going dark brown
Done	2-6 weeks, depending on protein and temperature
Arrest	Strain, then refrigerate at 2-4 °C (or freeze)

Done when: the solids have largely dissolved, the liquid is dark and deeply savory, and there’s no raw-protein or raw-bean note. Pleasantly funky and round, not putrid. Strain through cloth and refrigerate the liquid to halt the enzymes.

Method

Prepare and weigh the protein

Cook legumes soft, slice mushrooms, or use raw/lightly cooked meat, fish, or shrimp-shell trim. Weigh protein, koji, and water together — that is the total mash, and salt is a percentage of it.

Blend with koji, salt, and water

Combine protein, koji (~25%), salt (8-12%), and the water into a pourable slurry. Blend so the enzymes contact every surface. Seal into a jar (loose lid) or a vacuum bag.

Hold warm at 55-60 °C

Hold steady at 55-60 °C / 131-140 °F in a water bath, yogurt maker, or proofer. Massage or stir every couple of days. Expect visible liquefaction and a darkening, savory aroma within the first week.

Judge by aroma and feel

Ready when the solids have mostly dissolved, the liquid is dark and savory, and there’s no raw note — usually 2-6 weeks. It should smell appetizingly umami, not ammoniac or rotten.

Strain, season, and arrest

Strain through cloth and reserve the liquid. Refrigerate at 2-4 °C to stop enzyme activity, or freeze. The salt keeps it stable in the fridge for months. Reduce gently on the stove for a thicker, more concentrated garum if you like.

Tip

Garums are a clearing house for trim — beef scraps, mushroom stems, dry bread, shrimp shells. Any protein-rich substrate plus koji enzymes plus 8-12% salt at 55-60 °C becomes a savory seasoning liquid. Peaso garum uses cooked yellow split peas for a vegetarian version.

Caution

Animal-protein garums are a low-acid, warm-temperature process: the only barriers are salt and the warm hold, not acidity (pH stays above 4.6) and not refrigeration during the ferment. Do not drop below ~8% salt (lean to 11-12% for raw meat or fish), keep the chamber genuinely at 55-60 °C, and do not can these — they are fridge/freezer products. Ammonia or putrid smell, gas-bloating of the bag, or any pink/black surface growth means discard. These warm enzymatic processes are not validated as a botulism control; treat them as perishable seasonings and refer canning questions to NCHFP. See Safety and Botulism.

Variations / mix-ins

• Peaso garum: cooked yellow split peas as the protein — vegetarian, mellow, savory.
• Mushroom garum: roasted mushroom and trim — deep, vegetarian umami.
• Meat / fish garum: beef trim, chicken, or whole small fish — push salt to 11-12% and watch hygiene closely.
• Aromatics: a strip of kombu or a few toasted spices in the mash add background depth.

See also

• Amino Pastes — the full warm enzymatic method
• Rice Koji and Growing Koji — your enzyme source
• Time and Temperature — why 55-60 °C maximizes protease speed
• Dry-salt calculator and Salt converter
• Safety and Botulism