As well as herding cows, here at Maryland Farm we look after some much smaller beasts: starter cultures.
The 'friendly' bacteria used at the start of cheesemaking, they raise the acidity of the milk so that rennet can change it into curds. They also contribute to the ageing process, as the bacteria break down to release enzymes that determine the aroma, texture and taste of a cheese. So where one culture might give us a cheddar with a savoury, almost bovrilly hint another might give the gooseberry taste of Sauvignon Blanc.
Farmers used to use sour milk or whey but it was unpredictable: one culture would make delicious cheese but another produced a rancid lump. In the twentieth century, commercial companies ‘cleaned up’ such cultures by removing ineffective or dangerous strains of bacteria and supplied them freeze-dried. But, although convenient to use, some bacteria don’t survive freeze-drying and so the character and variation in flavour that live cultures produce is lost.
In the 1980s, the last big dairy using live cultures decided to stop and were going to throw them away until we stepped in. Our family now houses 22 different cultures and are the country’s only supplier, providing them to other cheese-makers. Just one vial of original culture can be used to make 28,000 tons of cheese; current production levels mean we have enough to last for 250 years.
We are fiercely proud of our cultures and our cheddar. Some cheddar-makers now use a starter culture often used in Swiss cheese but although the resulting sweet taste is popular with some, others think it has no place in cheddar. ‘I like the flavour in a Swiss cheese,’ says Giles Barber, ‘but it’s not right for traditional cheddar. Without our cultures, I can see all cheddars turning to this sweet taste and the original flavour dying out.’ Fortunately, thanks to our culture collection, it's something we don't have to worry about for a couple of centuries at least.