At the Aavin dairy in Sholinganallur, trace the journey of milk from cow to consumer

There is one thing I simply can't find at the Aavin dairy in Sholinganallur — cows. For a plant that processes close to 3.8 lakh litres of milk a day, all I see is just a lot of gleaming stainless steel, twisted into pipes and shaped into six enormous silos, standing guard at the entrance. I've just driven down the busy OMR, and entered the sprawling dairy. A ‘wash your hands and feet' board welcomes me as I enter the low, one-storied building, and I dip my feet in a trough of water laced with disinfectant. “Where are the cows?” I ask, as soon as I meet two Aavin employees. They smile indulgently; I suppose they get asked this a lot. “All our milk comes from Salem, Coimbatore, Tiruchi and Thanjavur. The Corporation does not allow cows to be reared within city limits,” I'm told. “But I've seen many cows in the city,” I argue. “We don't buy that milk; all our cows are registered, they're under the care of our veterinarians, while the farmers are taught good hygiene practices,”they say.

Cold chain

But wherever they live, they're milked by hand at 4 a.m. and the milk is transferred in an unbroken cold chain, until it reaches the dairy in massive 9000-litre tankers. There's one behemoth standing right outside the building, pumping the milk into the silo. “Touch the tanker; is it cold?” Dr. K. Anbarasu, the dairy bacteriologist, asks me. “Umm, no,” I reply. “Good, because that means the tanker is well-insulated. Now touch the valve.” It's cold and especially refreshing, in the searing heat of the afternoon. “That's milk at 6 degree C,” he smiles, adding that this is the only point where you can actually see the milk flow. “After this, you only get to see it in the packet.”

I'm happily surprised; this is automation of a very high order, and even though the romantic in me laments the lost drawing-milk-from-the-udder photo opportunities, the inner end-customer is secretly pleased at all the care lavished to keep milk germ-free.

The milk from the tanker — after passing quality control and laboratory tests — is pumped into the storage tank. But this milk, in its raw state, is rich in nasty micro-organisms, and since we don't care for that in our coffee, it undergoes many levels of purification, the best-known of which is pasteurisation. Dr. Anbarasu talks me through the HTST (high-temperature, short-time) process, where the milk is heated up to 74 degree C to 76 degree C, held at that temperature for 15 seconds and chilled rapidly to below 5 degree C. “This kills all the pathogens and it is this process, besides clarification (to remove dirt and dead organisms) and homogenisation (where big fat globules are broken down into little ones, to facilitate easy digestion), that makes it safe for the young and the elderly to drink the milk straight from the packet.”

Next, the milk is ‘standardised'. In lay terms, it's getting the fat and solid non-fat content right for the different coloured sachets of Aavin milk (for e.g., the blue toned milk sachets have 3 per cent fat and 8 per cent solid non-fat content, while the orange has 6 per cent and 9 per cent respectively). Until I get to this point, I have seen no sign of the milk that went into the silos. But now, with a reassuring hum, a big, complicated machine fills milk into previously sterilised sachets. But it's not just milk that puts in a late appearance; it's also people, who take over from the computers and machinery that have, at the flick of a button, been taking care of the various processes, including cleaning the gigantic silos. Here, the staff check the sachets, as they drop from the machine onto the conveyor belt. The sachets are then swiftly packed into trays and wheeled into the cold-storage room. This whole operation reminds me of a well-orchestrated ballet. Young lads whiz past me, pushing stand-up trolleys with a towering row of milk trays. In the bitingly chill, continuously cleaned cold-storage room, they quickly deposit the trays and whisk the trolleys away to fetch the next batch. The entire cycle takes less than a minute.

In a few hours time, I'm told, the milk will be dispatched (the vehicles leave the gate around 1.30 a.m.- 2 a.m.), and reach the consumers by 4.30 a.m. And this round-the-clock operation goes on without a break 365 days a year, as it has, for the last 48 years. Clearly, even while the cows might take a break, and go on maternity leave, Aavin keeps going. On and on.

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