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Home Cheese Making

How to make colby at home: yield, doses & aging

Updated 20264 min read

Colby runs about a 10–11% yield of milk weight and is aged at 12–13°C (53.6–55.4°F). Here are the make doses for a 2-gallon batch and the aging targets — every number cited to the source, not guessed.

How much colby does a batch make?

Colby yields 10–11% of the milk weight (midpoint 10.5%). Whole cow milk weighs about 1 kg per litre, so a 2-gallon (7.6 L) batch gives roughly 781–859 g of colby (about 820 g at the midpoint). Richer milk — raw, Jersey, or cream-topped — lands at the high end.

For a tighter estimate on a hard cheese like colby, the Van Slyke formula uses your milk’s fat and casein against a cheese-moisture fraction of about 0.45 — Curd runs this for you from a milk test.

Rennet, culture & calcium chloride for colby

For the 2-gallon batch above:

IngredientDose for a 2-gallon batch
Rennet (single-strength liquid)0.5 tsp (2.5 mL)
Calcium chloride (30% solution)0.5 tsp (2.5 mL) for pasteurized/store milk (skip for raw milk)
Bulk / direct-set cultureabout 0.5 tsp (2.5 mL), or scale a measured DVI packet to the batch

Double-strength liquid rennet uses half the volume. Too much calcium chloride (above ~½ tsp/gal) turns the curd bitter and rubbery — stay at the dose above.

Aging colby

Age colby at 12–13°C (53.6–55.4°F) at 80–85% humidity. It’s ready in about 1 month at the earliest — longer deepens the flavour. Flip the wheel every 3 days so it drains and dries evenly. Once the rind has dried, wax it to hold moisture through the long age.

FAQ

How much colby does a gallon of milk make?

Colby yields 10–11% of milk weight, so a gallon of whole milk (~3.9 kg) makes roughly 391–430 g. Richer milk yields more.

How much rennet and calcium chloride for colby?

For a 2-gallon batch: 0.5 tsp (2.5 mL) single-strength liquid rennet and 0.5 tsp (2.5 mL) of 30% calcium chloride (only for pasteurized milk).

What temperature do you age colby at?

12–13°C (53.6–55.4°F) at 80–85% humidity, ready in about 1 month at the earliest.

What you need to make Colby

Consistent cheese comes from measured doses and a steady aging temperature — eyeballing rennet or the cave is how batches turn rubbery or slip their moisture.

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The app for this
Curd does the colby math for your batch size
Set your milk volume and Curd gives you the yield, rennet, calcium chloride and culture dose for colby — then carries the wheel into the cave with a flip-and-wax aging log at colby's target temperature and humidity. Every number cited. Pay once, no subscription, works offline.
Get Curd on the App Store

Sources

Yield bands and aging targets are the cited published values for Colby; every milk, make and cave varies, so treat the doses as a tested starting point and adjust to your own results. Yield depends heavily on milk fat and casein — raw or Jersey milk yields more than store milk.