Counting instances of each item in column 1, where each cell in column 1 is a list of item

Apologies.. my actual problem is more complex than what I posted originally.. Making edits in this post to reflect that

If I have a list of delimiter-separated group of items in one column and a frequency of that list in second column , how can I use excel to get a count of each of the individual items.

I know that this isn't self-explanatory. So here is an example:

Given:
Column A (list) Column B (Frequency of this list)
apple, banana, apple 2
apple, orange, banana, banana 4
orange 3
pineapple, orange, banana, apple 1

I need a result like this:
Item Count of item
apple 9
banana 11
orange 8
pineapple 1

Can anyone help me with this?