Most organic milk is ultra high pasteurized (UHP) meaning it is heated at very high temperatures to kill all bacteria in order to extend its shelf life- typically 30-90 days if refrigerated (but only until the product is opened).     This is so that the milk (which may be twice the cost of non organic) can be shipped long distances and then stored on grocer's shelves for long periods without spoiling. 

But in keeping with the "no free lunch" theory, the unfortunate by-product of the UHP process is the killing of almost all the healthy enzymes in milk that are GOOD for your body!

So here's the  choice:  non-organic milk from cows treated with hormones and antibiotics or organic without healthy enzymes?  

Uh, pass the OJ please.....

(Note: There are a few brands of organic milk that do NOT use UHP, though most do and many do not disclose this on the packaging.)