19.In addition to having more protein than wheat does,[U] rice has protein of higher quality than that in wheat[/U], with more of the amino acids essential to the human diet.
这句中的划线部分,不明白的是higher quality 与than that(OG中称其指代protein)不怎么匹配。而且这个比较前后结构也不一样:rice has protein of higher quality 和that in wheat.