Here's another link with some ideas:
Keep in mind whatever one does, that if you’re going to overload the shells with canned goods, they are very heavy.
Therefore one doesn’t want to use long spans, as in the pantry shelves shouldn’t be longer than 30 inches
. And one doesn’t want to use MDF, if you’re going to have heavily loaded shelves, you need to use plywood.
You can look at Home Depot or Lowe's at their premise , unfinished pantry cabinets and maybe start there.