The sell-by dates of most conventional milk cartons indicate they...

The sell-by dates of most conventional milk cartons indicate they must be sold within two weeks of reaching the store's shelves; organic milk typically has up to eight weeks. The reason for the disparity lies in two differing methods of pasteurization. Credit: AP, 2006

Why are the expiration dates on cartons of organic milk so much farther in the future than those of conventional milk?

The sell-by dates of most conventional milk cartons indicate they must be sold within two weeks of reaching the store's shelves; organic milk typically has up to eight weeks. The reason for the disparity lies in two differing methods of pasteurization.

Pasteurization, you will recall, is the process of heating milk (or any food) to kill harmful bacteria. Most conventional milk is pasteurized by the "high-temperature, short-time" process, or HTST. With HTST, milk is brought to about 160 degrees and held there for 15 seconds. Eric Snowdeal, the milk and cream product manager for Organic Valley (a major producer of organic dairy products), said HTST milk typically has a sell-by date 16 to 20 days after bottling. Allowing for a few days to get from the plant to the store, that gives the retailer "about 14 days to sell it." Roughly 90 percent of conventional milk, he said, is HTST pasteurized.

Most organic milk, however, is ultra-high-temperature pasteurized, or UHT. It is brought to 280 degrees and held there for about two seconds. "That gives the retailer more like 60 days to sell the milk," Snowdeal said.

(If you're wondering about a low-temperature, long-time method of pasteurization -- referred to as batch or vat pasteurization -- large-scale dairies put it out to pasture when HTST showed up about a century ago.)

It's the market that has deemed that most conventional milk be pasteurized with HTST and organic milk with UHT. "There are far fewer organic-milk consumers than conventional," said Snowdeal. "Because UHT gives organic milk a longer shelf life, it allows stores that much more time to sell that shipment of milk." UHT, he continued, makes shipping organic milk easier over long distances. "It makes it easier for a small store in the middle of nowhere to carry organic milk."


What is black rice?

If you've seen black rice at the market, it is...

If you've seen black rice at the market, it is probably Forbidden Rice, a jet-black medium-grain rice grown in China and imported by Lotus Foods. Like brown rice, black rice has not had its outer layer, the bran, polished off; it is a whole grain, full of nutrients and fiber. When cooked, the taste is mild and a little sweet. It stays black, but exudes a little purple juice. Credit: Lotus Foods

If you've seen black rice at the market, it is probably Forbidden Rice, a jet-black medium-grain rice grown in China and imported by Lotus Foods. Like brown rice, black rice has not had its outer layer, the bran, polished off; it is a whole grain, full of nutrients and fiber. When cooked, the taste is mild and a little sweet. It stays black, but exudes a little purple juice.

The package directions would have you combine 2 cups black rice with 31/2 cups salted water and simmer for 30 minutes. When I'm cooking any unfamiliar rice (that is, any rice that's not Uncle Ben's or Carolina), I cook it like pasta: Bring a large pot of salted water to boil, add rice and cook until it is just tender. Drain well, then return it to the dry pot to collect itself for a few minutes.

A winemaker. A jockey. An astronaut. We’re celebrating Women’s History month with a look at these and more female changemakers and trailblazers with ties to long Island. 

Celebrating Women's History Month at Newsday A winemaker. A jockey. An astronaut. We're celebrating Women's History month with a look at these and more female changemakers and trailblazers with ties to long Island. 

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