What is the difference between goats’ milk (and cheese) compared to cows’ and sheep’s?
Each mammal produces slightly different milk. Although the constituents are broadly the same (water, lactose sugar, fat, protein, minerals and nutrients) the exact make up of each milk varies, depending mainly on the species (Polar Bear milk is almost 35% fat – they need it!), how that animal is bred, and finally how it is fed.
Even within the same species, variances can be huge – the Nigerian Dwarf goat’s milk can be 6.5% fat, the more common Saanen goat’s just 3.3%.
Goats produce much less milk than a cow (four litres compared with 30), but the percentages of fat, protein and lactose in goats’ milk are broadly similar to cows. One difference, however, is that goats fully digest the carotene colouring in grass – which explains why goats’ milk and cheese is white, whereas cows’ milk and cheese can be yellow.
Can you have goats’ milk if you are lactose intolerant?
There is an urban myth that goats’ milk is better for you if you are lactose intolerant. Goats’ milk, however, has roughly the same level of lactose as cows’ and sheep’s. The myth seems to come about because many people believe goats’ milk is easier to digest – even as early as 77 BC in Ancient Rome, Pliny the Elder was declaring “Goats’ cheese is more easy to digest than cows’” [Naturalis historia].
Even though goats’ milk does contain roughly the same elements as cows’ milk, the composition and behaviour of the fat and protein is different and unique – which might explain why many people believe it is easier to digest.
The fat globules in goats’ milk are smaller and more naturally homogenised (they don’t join together and clump as easily– like you get with the cream rising to the top on cows’ milk. That’s also why it is hard to make butter from goats’ milk.)
There is also more lipase enzyme in goats’ milk than cows’, which breaks down fat and gives the piquant, peppery flavours and aromas you can get in goats’ (and sheep’s) cheese.
The higher proportion of smaller chain fats in goats’ milk is what gives goats’ cheese its distinctive goaty flavour. Goats’ milk also shows the aromatic compounds from their quite diverse herbaceous feed as browsers – thyme/lavender/rosemary/barnyard/earthy/hazelnut.
The proteins in goats’ milk also differ in composition from cows’ milk. In fact they have less of the protein that is needed to make a ‘firm’ curd in cheese making and therefore produce a more delicate, fragile curd.
These delicate curds and more naturally homogenised milk are the reason goats’ cheeses are often small, fresher, ‘lactic-acid’ slightly ‘tart’ cheeses, often maturing with a wrinkly rind caused by a yeast that is also very prevalent in raw goats’ milk – Geotrichum.
Do you want to know why goats’ cheese tastes goaty? Click here >