views exposed filter on field collection item
Field collection items can perfectly participate as Views filters. The key is to use Views relationships. You can create a relationship for the portfolio field, and then in the filter specify to use that relationship. That will cause the filter to analyze the field collection's contents, as opposed to the host entity's.

For example, here I established a relationship to an image gallery collection, created a file id filter, and associated the filter with the collection. The fid filter is also exposed: