Re: Treatment of long life milk to remove bacteria?

> We were wondering if long-life milk has more heat treatment that other
> types of milk to make it last longer.

Basically, yes.

From the National Food Safety Database: http://www.foodsafety.ufl.edu/consumer/nc/nc182.htm

Ultra-high-temperature (UHT) milk is regular fluid milk that is packed in an airtight, sterilized, cardboard (tetra brik) container. The product is treated by flash sterilization at 290 ° F. (twice the temperature of normal pasteurization). This high temperature kills all bacteria or microorganisms. The milk is then packed into sterilized containers. This milk is then shelf-stable for six months. After six months, the flavor and color begins to change and the product thickens. It is still safe but may not produce the desired effect in a recipe. Once opened, the milk must be refrigerated.

From: http://www.foodsafety.ufl.edu/consumer/nc/nc188.htm

Milk must be heated with agitation so every particle of the milk, including the foam, reaches a temperature of 145° F and then held for 30 minutes at 145° F. Another method of pasteurization is to heat the milk to 161° F and hold it for 30 seconds. Consumers should only consumer dairy products that are made from pasteurized milk.

Both blurbs were authored by: Angela M. Fraser, Ph.D., Food Safety Specialist and Carolyn J. Lackey, Ph.D., R.D., Department Extension Leader, Family and Consumer Sciences, Foods and Nutrition, Box 7605, North Carolina State University, Raleigh, NC, 27695-7605.

Other good (but more technical) web pages on milk pasteurization: http://class.fst.ohio-state.edu/Dairy_Tech/11.%20Heat.htm
http://www.dasc.vt.edu/dasc2474/1r7proctech.htm