スクリプトで子オブジェクト全ての色を変える方法

using UnityEngine;
using System.Collections;
using UnityEngine.Networking;

public class TankMovement : NetworkBehaviour {

	public float moveSpeed;
	public float turnSpeed;

	private Rigidbody rb;
	private float movementInputValue;
	private float turnInputValue;

	// ★
	private Component[] meshes;

	public override void OnStartLocalPlayer(){

		// ★
		meshes = gameObject.GetComponentsInChildren<MeshRenderer>();

		// ★
		foreach(MeshRenderer mesh in meshes){
			mesh.material.color = Color.red;
		}

	}

	// ＊＊＊＊＊＊＊＊以下、省略＊＊＊＊＊＊＊＊＊＊＊＊＊