It is written:

Food is palatable if it doesn't taste bad, and those with a fine palate may frequent the more expensive restaurants.

Tying in the selective notion, I would write:

We select our ingredients using a fine palate.

The title of the question speaks of positive connotation and food. I suggest making the phrase therefore positive, and referring to fine palate for the notion of food. It is written:

Food is palatable if it doesn't taste bad, and those with a fine palate may frequent the more expensive restaurants.

Tying in the selective notion, I would write:

We select our ingredients using a fine palate.

It is [written][1]:

Food is palatable if it doesn't taste bad, and those with a fine palate may frequent the more expensive restaurants.

Tying in the selective notion, I would write:

We select our ingredients using a fine palate.

[1]: https://books.google.ca/bookshttps://books.google.ca/books?id=g5nYBQAAQBAJ&pg=PA80&lpg=PA80&dq=fine palate meaning&source=bl&ots=8l9x3Um67H&sig=J-dAA923dX9x9vSn6mCKfL0dmOM&hl=en&sa=X&ei=fTCZVeq4F8r2-AG3_4OACQ&ved=0CDMQ6AEwCA#v=onepage&q=fine%20palate%20meaning&f=false

It is written:

Food is palatable if it doesn't taste bad, and those with a fine palate may frequent the more expensive restaurants.

Tying in the selective notion, I would write:

We select our ingredients using a fine palate.