Every year, 7.6 million tonnes of food is lost or wasted in Australia. When we think about this, we might picture mouldy fruit, stale bread and overly full fridges. But in fact, almost half of this waste happens before food ever gets to us. Waste is common in food production, processing and transportation. For example, the process of making cheese from milk results in a comparatively small amount of cheese and a lot of whey – up to 90% the mass of the raw milk. Whey is useful, as it still has about half the nutrients of milk. But whey…