What is this ????

I make my own fertilizer for tomatoes and pepper etc. and notice something that is new to me.  In my fertilizer mixture I use coffee grounds. I save them in a coffee can and keep them sealed after adding other grounds to the can until it is full. Before making the mixture I bake them in the over at 300 degrees for 1 1/2 hours.  However this year I noticed little white worms in them (same as last year). I have no ideal what this is or how they got in the used grounds. I put the grounds in a container lined with foil and set out in the 90 deg. sun to dry them. I also noticed they can not take to heat, as I was scraping around to mix the ground up a little I noticed that these thing jump around in the sun.
I have taken a picture of the worms and a short video on them jumping and will post them as soon as I can figure out how to.
Has anyone seen anything like this, or know what the worms are, or how they get into the grounds ??
Regards,
kt

I made several attempts to get a better picture using two different cameras but didn't do much better, I will add the best one here. And no we do not have a County Entomologist that I am aware of but will ask around. This is a rural area and we don't have a lot here, sorry..
Actually the best view is of them jumping, but it is a video and I can't figure out how to post it. I will gladly send it to you (or anyone else) if you like. Just email me at familyties66@bellsouth.net and I will attach it to a reply. The video is 5.5 MB. and can be seen using Windows Media Player.
Regards,
kt

We have noticed little maggot like worms in our coffee grounds from our espresso machine if I don't empty the spent grounds container soon enough.  I figured maybe larvae brought on by warmth but don't know their origin.  Will be interested in replies to this post.  Mine don't jump as far as I know.