If we take "the fruits array" to mean the specific example given, then there is only one valid candidate. Given that, it's not clear that a loop is needed, let alone a while loop.
If we're talking about any list of fruit names, then like Walter said, it's important to be specific about what you want when you say "apples elements". It's also still unclear why a loop is needed.
% a list of fruit names
fruits = ["apricot", "pears", "pineapples", "apples", "Apple"];
% true for "apple" or "apples" (case-insensitive)
isapples = ismember(lower(fruits),{'apple','apples'});
% display the elements of the fruits array which meet the simple test
fprintf('%s\n',fruits(isapples))
