Edit in JSFiddle

var Main = {
methods:{
change(){
console.log(this.options[this.value])
}
},
    data() {
      return {
        options: [{
          value: '选项1',
          label: '黄金糕'
        }, {
          value: '选项2',
          label: '双皮奶'
        }, {
          value: '选项3',
          label: '蚵仔煎'
        }, {
          value: '选项4',
          label: '龙须面'
        }, {
          value: '选项5',
          label: '北京烤鸭'
        }],
        value: ''
      }
    },
    created(){
    	setTimeout(()=>{
    		this.options.forEach((item,index)=>{
        	if(item.value==='选项5'){
        	 	 this.value=index
       		 }
				})
    	},1000)
    }
  }
var Ctor = Vue.extend(Main)
new Ctor().$mount('#app')
@import url("//unpkg.com/element-ui@2.4.6/lib/theme-chalk/index.css");

<script src="//unpkg.com/vue/dist/vue.js"></script>
<script src="//unpkg.com/element-ui@2.4.6/lib/index.js"></script>
<div id="app">
  <template>
  <el-select v-model="value" placeholder="请选择" @change="change">
    <el-option v-for="(item,index) in options" :key="item.value" :label="item.label" :value="index">
    </el-option>
  </el-select>
</template>
</div>