非蛋白质氨基酸是相对于组成蛋白质的20种常见氨基酸而言，指除组成蛋白质的20种常见氨基酸以外的含有氨基和羧基的化合物。非蛋白质氨基酸多以游离或小肽的形式存在于生物体的各种组织或细胞中。
茶氨酸是茶叶中特有的、游离的非蛋白质氨基酸，其含量与茶叶品质呈正相关。
Theanine is a special kind of free amino acid in tea, which is not the constituent of protein, its content has positive relation with tea quality.
淀粉、非还原糖、可溶性蛋白质、游离氨基酸、叶绿素含量在陈化过程中均保持下降趋势。
The content of starch, non-reducing sugar, soluble protein free ammo acid, chlorophyll kept reducing during aging.
脯氨酸：非必需氨基酸的一种，广泛存在于很多蛋白质特别是胶原中。
Proline: one of the nonessential amino acids, found in many proteins, especially collagen.
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