Pasteurized and/or irradiated foods are known to be depleted of some vitamins, enzymes and proteins. At the same time, these processes can cause a 3 to 5 log kill of pathogens and extend shelf life. Sometimes it's difficult to separate the pasteurization from other nutritional factors. For example, pasteurized milk is usually from grain-fed cows, while raw milk is most often organic and grass-fed. Is raw milk better because because it's unpasteurized, or because it's grass-fed? Is pasteurization or irradiation of food ever advantageous? If so, under what circumstances? (Keep in mind that I'm not asking the libertarian question as to whether the government should force producers to pasteurize or irradiate, or withhold such information from consumers.)
Well, I always pasteurize my raw milk before I make yogurt. That's to give the "good" bacteria a fighting chance. There's certainly no expectation that raw milk is completely - or even partially - bacteria free, so I consider this an essential step. But otherwise, I'd certainly not bother to pasteurize my milk. I consider the "rawness" to be an asset, not a liability.
However, I think that raw, grass-fed milk is good because it's grass-fed, not necessarily because it's raw, and pasteurizing it to make yogurt doesn't take one whit away from the fact that it's hormone-free. On the other hand, if it wasn't necessary to pasteurize the milk to make yogurt, I wouldn't do it.
the reason that many people with lactose intolerance can actually drink raw milk is because the "good bacteria" produce B-galactosidase, which includes lactase, which breaks down lactose. Its the same reason that people with lactose intolerance often have no problem with yogurt
I liken pasteurization to vaccination. It is a sub-optimal solution, but when dealing with population statistics both make tremendous sense. The last two generations have had the luxury to forget the horrors of polio, small pox, measles and dozens of other horrible diseases. They have also forgotten how often people, particularly children, fell ill from contaminated milk.
Never forget it is polio and brucellosis that are actively harmful. For 98% of the population vaccines and pasteurization are merely less nutritious. While I don't want to take away anything from the 2% harmed by vaccines or pasteurization, they are far, far fewer than were harmed by diseases before vaccination and pasteurization.
I was just looking into this and surmised that pasteurized milk does kill bacteria, but all the bacteria--good and bad. This provides and open door for outside bacteria to jump in after the process and excellerates decomposition. The stories they tell about raw milk leading to disease is much less common than with pasteurized products.
Now grass-fed versus grain-fed is no contest: grass-fed is SO much healthier for you because the cows are healthy and don't have to be pumped full of antibiotics to survive a toxic diet and abhorrent conditions. I definitely go for raw, grass-fed when I partake in dairy.