Only temporarily (and only assuming the liquid nitrogen was cold as the background -- liquid helium temperatures are really the temperatures you're going for if you want to match thermal background radiation, and at that temperature nitrogen is a solid).
Let's say at t=0, you have a warm spacecraft with internal heat sources (people, fuel cells, equipment) and a cold jacket of ultracold material (liquid helium, solid nitrogen, whatever). At that time, the jacket is emitting blackbody radiation that looks like the thermal background of the universe, and the ship is invisible. At t=t1, sometime later, the jacket has absorbed some heat from the warm interior of the ship. Now, one of two things happens. Either the heat goes into changing the state of the jacket (say, boiling off some liquid helium), in which case the remaining jacket's temperature remains the same and the ship stays invisible (but for the venting gasses), or the jacket warms up (say, if you've just warmed the solid nitrogen coat, but haven't reached a phase transition), in which case the blackbody spectrum changes and the ship becomes more visible than before. In the first case, you're fine until you run out of jacket to boil off; then your ship is visible. In the second case, the jacket keeps warming until it has the equilibrium temperature of the interior of the ship. If it hasn't undergone a phase transition (e.g. let's say it started as ultracold iron, and now it's just lukewarm iron), it now has a blackbody spectrum matching the naked ship, and either way your ship is visible.
The next thing that you'll probably say is, "Well, what if I keep the jacket cold?" The question is, how will you do that? If you have a magic heat sink for the heat that the jacket will absorb from the interior, just pump the interior heat directly into that sink -- no need for the jacket. Unfortunately, any scheme for avoiding exterior radiation will presumably involve pumping heat into an interior reservoir, which will get hotter and hotter until the heat is no longer containable, and the ship will be (briefly) VERY visible.
So the short answer is, no: your interior heat has to go somewhere, and while you can delay its emission, you can't prevent it. (Now, if the goal is to temporarily cloak a ship, that's doable, at the expense of having to dump more heat later.)