Starter Culture Calculator

No -- Ripening Temperature and Target pH are set entirely by Culture Type (Mesophilic vs. Thermophilic) and have zero relationship to Milk Volume. A 2-gallon batch and a 50-gallon batch of the same culture type ripen at the identical temperature and target the identical pH; only Culture Units (packets) scales up with the larger batch.

The calculator compares your Target Set Time to the style's standard set time (60 minutes for Mesophilic, 45 for Thermophilic) and scales Culture Units (packets) up when you're asking for a faster ripen than standard. More active culture accelerates acidification, which is what lets you hit renneting readiness sooner than the standard timeline.

Culture Type sets both the ripening temperature and the pre-rennet target pH: Mesophilic cultures ripen at a moderate 86°F toward pH 6.4 and suit cheddar, gouda, and brie, while Thermophilic cultures ripen at a much hotter 108°F toward a slightly lower pH 6.2 and suit mozzarella, parmesan, and Swiss. Both targets are the preacidification point reached before rennet goes in, not the much lower pH the curd reaches hours later. Using the wrong type for your recipe means ripening at the wrong temperature entirely, not just a minor timing difference.

Yes, at a fixed Target Set Time and Culture Type -- Culture Units (packets) is Milk Volume multiplied by the base dosing rate and then adjusted by the same time factor regardless of batch size, so doubling Milk Volume doubles Culture Units (packets) proportionally. Scaling a cheese recipe up or down is mostly a matter of scaling Milk Volume.