private void extractProperties(InputStream inputStream, Metadata metadata) throws TikaException {
        try {
            NSObject rootObj = PropertyListParser.parse(inputStream);
            if (rootObj instanceof NSDictionary) {
                NSDictionary dict = (NSDictionary)rootObj;
                for (String k : dict.keySet()) {
                    String v = dict.get(k).toString();
                    metadata.set(IWORKS_PREFIX + k, v);
                }
            }
        } catch (SecurityException e) {
            throw e;
        } catch (Exception e) {
            throw new TikaException("problem with plist", e);
        }
    }
All iWork 13 files contain this, so we can detect based on it
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-apple-module/src/main/java/org/apache/tika/parser/iwork/iwana/IWork13PackageParser.java