SQL & PL/SQL :: How To Search For A Particular Text In String Column

I have one table for eg. TB_Fruits.

In that i have one column FruitsName(Varchar)

In that column i am storing string in comma separated values.

Select FruitsName from tb_fruits;
Result: orange,banana,apple

Now the issue is suppose if i try to insert any of these fruits name again then it should not allow me to insert.

Suppose now if i try to insert ('grapes,banana')
or
('apple,grapes')

the orange,banana,apple can be in any position.

How to check if any of these names already exist or not in the column fruitsname?

I cannot use like or INstr function here. because the position is not fixed not even string.