Whey, Co-products & Cow Water
Whey turns cheese sites' effluent economics upside down, and evaporator condensate ('cow water') is a water source hiding in the milk itself.
10 min read · Jacob Willis, Net Zero Lead · Last reviewed July 2026
Make a kilogram of cheese and roughly nine litres of whey appear beside it, whether you wanted them or not. For most of the industry's history whey was a disposal problem, and in energy terms it still shapes cheese-site economics more than any machine on the floor: sent to drain it is catastrophically expensive effluent, processed it becomes valuable product at a real energy cost, and either way the site's numbers make no sense until whey is accounted for. This lesson covers the whey decision, the co-product logic behind it, and the sector's other hidden stream: the "cow water" that evaporators recover from the milk itself.