From the Family Files..Why does Organic Milk Last Longer than Conventional Milk?

This weekend, my brother-in-law wanted to know why organic milk lasted so much longer than conventional milk. "It's all in the processing" I told him. This was not a good enough answer for him. Nor should it be. It was on to the Internet to find a more suitable answer. I felt that Craig Baumrucker, professor of animal nutrition and physiology at Pennsylvania State University summed it up best in his interview with the folks from the Scientific American in May of 2008:

"So what is it about organic milk that makes it stay fresh so long?Actually, it turns out that it has nothing to do with the milk being organic. All "organic" means is that the farm the milk comes from does not use antibiotics to fight infections in cows or hormones to stimulate more milk production.Organic milk lasts longer because producers use a different process to preserve it. According to the Northeast Organic Dairy Producers Alliance, the milk needs to stay fresh longer because organic products often have to travel farther to reach store shelves since it is not produced throughout the country.

The process that gives the milk a longer shelf life is called ultrahigh temperature (UHT) processing or treatment, in which milk is heated to 280 degrees Fahrenheit (138 degrees Celsius) for two to four seconds, killing any bacteria in it.

Compare that to pasteurization, the standard preservation process. There are two types of pasteurization: "low temperature, long time," in which milk is heated to 145 degrees F (63 degrees C) for at least 30 minutes*, or the more common "high temperature, short time," in which milk is heated to roughly 160 degrees F (71 degrees C) for at least 15 seconds.

The different temperatures hint at why UHT-treated milk lasts longer: Pasteurization doesn’t kill all bacteria in the milk, just enough so that you don't get a disease with your milk mustache. UHT, on the other hand, kills everything.

Retailers typically give pasteurized milk an expiration date of four to six days. Ahead of that, however, was up to six days of processing and shipping, so total shelf life after pasteurization is probably up to two weeks. Milk that undergoes UHT doesn’t need to be refrigerated and can sit on the shelf for up to six months.

Regular milk can undergo UHT, too. The process is used for the room-temperature Parmalat milk found outside the refrigerator case and for most milk sold in Europe.

So why isn’t all milk produced using UHT?

One reason is that UHT-treated milk tastes different. UHT sweetens the flavor of milk by burning some of its sugars (caramelization). A lot of Americans find this offensive—just as they are leery of buying nonrefrigerated milk. Europeans, however, don’t seem to mind.

UHT also destroys some of the milk’s vitamin content—not a significant amount—and affects some proteins, making it unusable for cheese."

Needing a more practical application, I headed over to the Organic Valley website. They have a great FAQ section that I can highly recommend. Here is their answer to the commonly asked question "Is my carton of milk good past the sell-by/expiration date?"

Their answer: "We cannot recommend consuming any milk product past the sell-by date. We guarantee its freshness upto the sell-by date if unopened. Once opened, a milk product is freshest tasting within 5 days."

www.organicvalley.coop/



And a bit of information on that USDA Organic Label. If you see it on a food/beverage product, know that the product was made with:

No synthetic hormones
No antibiotics
No synthetic chemicals
No herbicides
No pesticides
No fertilizers
No Genetic Engineering (GE)
No irradiation
No cloning
www.ams.usda.gov/nop/

But is organic food better for you-nutritionally speaking? From the American Dietetic Association's website (www.eatright.org)

Research shows that nutritionally there is no evidence that organic produce is better or safer than conventionally grown produce. Organic foods differ from conventional foods only in the way in which they are grown and processed.