Need some help regarding a feed from feedburner.

Today I was just looking at some recipes at when I looked at a particular recipe which would send an email about the free app of the week on Apple App Store. The recipe used a feed which was generated by feedburner. The feed was:

I would like to know how this feed could have been generated? And is there any way of generating similar feeds of any twitter handle?

This was the recipe which I created using the feed: