code: public static void enableSerialization(Configuration conf) {
  		String serClass = TupleSerialization.class.getName();
  		Collection<String> currentSers = conf.getStringCollection("io.serializations");
  
  		if(currentSers.size() == 0) {
  			conf.set("io.serializations", serClass);
  			return;
  		}
  
  		// Check if it is already present
  		if(!currentSers.contains(serClass)) {
  			currentSers.add(serClass);
  			conf.setStrings("io.serializations", currentSers.toArray(new String[] {}));
  		}
  	}
docs: Use this method to enable this serialization in Hadoop