It seems we have concluded that OP is purchasing the Durian in SFO and wanting to bring it to IAH so the CBP and APHIS issues are not pertinent.

If the issue, then, is safety and comfort of travel for the Durian, I'd suggest getting a Pelican Case and then inside the Pelican Case getting a styrofoam case, and inside of that, putting frozen ice sacks to keep it cool, and wrapping all that (inside the styrofoam) in a sealed plastic bag.

That, to me, is about the most secure way to transport a Durian from SFO to IAH.

I've never had UA agents ask me what was in my luggage when using standard luggage - I've only been asked that when shipping a box or non-standard item.