PHP _post change values

I have a form with multiple checkboxes:

<input type="checkbox" name="check[]" value="Option 1">
<input type="checkbox" name="check[]" value="Option 2">
<input type="checkbox" name="check[]" value="Option 3">

This form sent 2 mails, one with the values of the selected checkboxes:

foreach ($_POST['check'] as $value) {
        $check_msg .= "$value / ";
    }

In other have to change the values of selected checkboxes, for example: If checkbox 1 is checked instead of send Option 1, send: "Lorem ipsum dolor sit amet..."

How would I do this?

Thanks in advance!