Cow gal is right, it looks like shredded cardboard pressed into pellets. But adding water to it and letting sit is a must (IMO). If you pour 2 inches of beet pulp in the botom of a bucket and fill the bucket a little over half full of water the next morning you'll end up with an oatmeal like substance (darker), but very little water showing. The fact that it expands that way tells me, and others around here that use it, there is a real risk of it swelling in the horses throat and getting stuck without adding water to it and letting "swell" .
Our horses don't like it plain, won't eat it, but mix some grain or molassas in it and they love it. Not only is it a great fiber source but it a great way to add fluids to their diet, prevention of colic, keep weight on during long trailer trips, etc.
I wouldn't think that it would make our TB hot, but he has been off beet pulp for the last 2 days and he is back to normal, were I fill he has been hot since he has been on it. Does not effect our other horses, but one won't eat it no matter what we do, and he loves soaked rice bran (?)
Alan