只有纯牛奶怎么做奶油

{"name":"\u53ea\u6709\u7eaf\u725b\u5976\u600e\u4e48\u505a\u5976\u6cb9","type":"\u56fd\u4ea7\u5267","area":"\u6cf0\u56fd","year":"2009","lang":"\u5176\u5b83","play":"\u8d85\u6e05","type1":"\u56fd\u4ea7\u5267"}