A Swindon dairy produces the nation's milk - and the Advertiser has had a sneak peek inside the factory.

Berkeley Farm Dairy in Wroughton processes enough dairy from its own and other farms to impress even Gregg Wallace - 30,000 litres.

While it makes its own organic dairy products you may have had milk from here without even realising.

Ed Gosling, of the Gosling family which owns the dairy, first showed the huge tanks where raw milk is pumped into. (Image: Newsquest)

It has to be used within three days of delivery, but mostly the 30,000 litres of dairy product they produce daily is processed in 24 hours.

The milk is lab-tested for bacteria and antibiotics. A blue pigment is added which is eaten by the bacteria. 

The more bacteria, the less time the blue colour sticks around. If it turns blue too soon it the milk is returned to the farm which only happens around every three years.(Image: Newsquest)

Next the milk is rapidly heated from five to 75 degrees for 15 seconds, killing 99.8 per cent of bacteria. 

Most is not homogenised, a process Ed blames for lactose intolerance - although he admits he has no evidence for this.(Image: Newsquest)

Three-quarters of the milk at Berkeley Dairy is organic, but it also produces non-organic on separate days to minimise cleaning.

“People cannot get enough organic milk right now," Ed said. He sells leftover organic milk to Muller.(Image: Newsquest)

In this same room, churns turn milk into 1000 blocks of butter daily which is patted by hand while cream, separated by a centrifuge is poured into pint bottles.

From here some milk turns right, where it is made into 65,000 weekly litres of kefir - a thick fermented yogurty drink - for the company Biotiful, found in “all the supermarkets”.

The milk for kefir is sterilised and cultures added. Bottles are filled, flavour added and then lidded and labelled by machine. Special pumps must be used to move the kefir because it is so thick.

Other milk turns left - where it is bottled into either the dairy’s own brand or for national grocery delivery company Abel & Cole. They are Abel & Cole’s sole provider of 30,000 litres of milk a week.(Image: Newsquest)

As well as their own farm of Guernsey cows, milk comes from another four local farms, two of which are non-organic.

The dairy produces their own brand found in shops in Swindon and beyond but also produces under license for Abel & Cole, and soon Ocado.(Image: Newsquest)

“Abel & Cole is great, because our milk gets to go all over the country”, Ed said.

For Abel & Cole they bottle in lightweight, reusable plastic bottles - produced to their own design and cheaper to transport than glass.

They have planning permission for solar panels which will eventually pay for 70 per cent of their energy bills, which have recently skyrocketed to £200,000 yearly, and charge their fleet of electric milk floats.(Image: Newsquest)

They deliver to around 3,500 households around Swindon. As the drivers are going to the houses anyway, Berkeley has started also delivering organic juice, vegetables and even flowers.

Ed remarked: “The flowers are surprisingly popular actually.”(Image: Newsquest)

The dairy is situated metres away from houses, and the Advertiser recently reported on a neighbour’s noise complaints.

Ed admits that there have been noisy times as they upgrade the site - but he says is now quiet and a valuable asset, employing 55 people from Swindon and Wroughton.

Outside, a tasty smell of mango fills the air. Someone has spilt a bag of flavour for the kefir. Ed seems annoyed - at least it wasn’t spilt milk.