Cold-filtering is a way of clarifying beer with a reduced lagering time. Beer (lager particularly) becomes clearer with extended storage, which allows proteins and other particles to coagulate and settle out of suspension. The beer can then be drawn off and bottled. One way to reduce the time required is to chill the beer, causing these molecules to "clump" and be easily filtered out. The upside is that the time from brewing to finished product is shortened, thereby boosting productivity, whereas the downside is that cold-filtering also removes many components that contribute flavour and body to beer.
¡°Heat-pasteurised¡± is a redundant phrase since pasteurisation means heating to kill microbes.
Some beers are bottle- or cask-conditioned, meaning that live yeasts are still in the beer in its container. Most mainstream beers are either filtered or pasteurised, to remove or kill all yeasts and bacteria. This makes for a more stable product with a longer shelf life.
Pasteurisation is more expensive and tends to alter the flavour. Filtration is cheaper, leaves a clearer beer, and has less effect on flavour.
Source : FAQ of alt.drinks.beer