Why Does Organic Milk Last Longer Than Non-Organic Milk?

by Nicola Temple on October 13, 2011

I come from a family of sporadic milk drinkers. This makes being the primary shopper a challenge. One week, I can’t seem to keep it in the fridge, the next I’m pouring some foul-smelling dregs down the sink.  As a result, I spend a lot of time looking at expiration dates.  I’m that annoying shopper that messes up the shelves looking for the carton with the best date. I’m sorry; it’s a matter of fridge survival.  If you too are an expiration date aficionado you may have noticed that organic milk has a much longer shelf life than its non-organic counterparts. So why does organic milk last longer?

As much as I would like to say that it’s because organic milk is fresher, it is quite often the opposite.

As there are fewer organic dairy producers, organic milk often has to travel greater distances to reach the shelves. This means it needs to be processed in a way that will extend its shelf life.

Most organic milk in the US has been treated with an ultrahigh temperature process (UHT), which kills all bacteria and gives it a shelf life of six to nine months.

why does organic milk last longer

Why does organic milk last longer? It doesn't. It's simply that most organic milk is UHT. CC image courtesy of Fishhawk on Flickr.

UHT vs. Pasteurization

Most milk is pasteurized. The milk is heated to 145oF for 30 minutes or more, or it is heated to 160oF for 15 seconds or more. This process kills some of the bacteria in the milk and therefore slows the growth of bacteria that cause milk to sour. However, it doesn’t kill all the bacteria.

UHT, on the other hand, heats the milk up to a whopping 280oF for 2-4 seconds and kills anything living in there. As a result, the milk has an exceptionally long shelf life and doesn’t need to be refrigerated prior to opening. However, as American consumers find non-refrigerated milk a bit creepy, UHT processed milk is often given similar packaging and sold in the refrigerator aisle alongside the pasteurized milk. Tricky!

Problems with UHT

There are many concerns about UHT processing. First, because such a high temperature is used, some of the sugars in the milk actually become caramelized, giving the milk a sweeter flavour that some people dislike.

Second, proteins are denatured at high temperatures, so there is concern that UHT processing destroys some of the beneficial vitamins and proteins.

Not all organic milk is equal

I was raised on a small hobby farm and my Grandpa would milk our one cow, Penelope, every morning. I would be at the breakfast table with cereal poured and he would walk in with his pail and literally pour the milk from the pail onto my cereal. It was still warm and there would be chunks of cream on top. To be honest, it put me off milk for a REALLY long time. How I longed, for cold, sterile, skimmed milk! The things kids get into their heads!

However, we can’t all have our own cow, so we seek out what we think is the next best option – organic milk. As a result, organic milk has seen the greatest increase in demand of all organic products in the US.

Certified organic milk products must abide by the USDA organic standards, which includes no use of antibiotics or hormones, no GMO feed, no pesticides where the animals graze, and access to the outdoors for part of the time.

However, what is the point of paying more for an organic product if the benefits of the product are reduced as a result of processing?

Luckily, not all organic milk is equal. Travel to Australia or Europe and most organic milk has not been UHT treated, it is pasteurized.  Not all organic milk in the US is UHT treated, so check the label before you buy.

The Cornucopia Institute, which advocates for family-scale farming, produced a report card on organic dairy producers in the US. It rates 68 organic dairy farms on a number of criteria including pasture time the cows receive, the ownership structure of the farm, and use of hormones and antibiotics. It’s worth checking out your favorite organic dairy products, to see how they rate.

So the answer to the question ‘why does organic milk last longer?” is… it doesn’t. UHT milk lasts longer than pasteurized milk, regardless of whether it is organic or not. It just happens to be that the majority of organic milk in the US is UHT processed as it has to travel greater distances. If you can source a local organic product that is not UHT processed then well done – please share it in the comments below so other readers can benefit.  Of course, there’s always the raw milk option as well.

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