乳酸菌会合成一部分 B 族维生素，也可能产生少量维生素 ；可维生素 C 不耐久放，发得越久流失越多。泡菜的价值在蔬菜、纤维和活菌这个组合，不在某一种被放大的神奇维生素。
机制 · 发酵加了什么，丢了什么
先看底子。大白菜提供维生素 C、维生素 K、叶酸和纤维；辣椒粉带来类胡萝卜素；蒜和姜带来各自的活性物质。这是一盘蔬菜沙拉级别的底子，热量很低（USDA 数据，每 100 g 不到 30 kcal）。
发酵带来的变化：
乳酸菌会合成一些 B 族维生素（比如核黄素、部分形式的叶酸），也可能产生维生素 ，给原料添了一点酸性环境和微生物代谢，可能让一部分矿物质和植物化合物更容易吸收产生新的代谢产物：乳酸、其他有机酸，以及一些正在被研究的生物活性肽 但有两点要说实话。维生素 C 不稳定：发酵得久，再加上接触空气，会流失一部分，所以别把熟成很久的泡菜当成维生素 C 的主要来源。变化幅度因批次而异：自制的、不同作坊的、熟成程度不同的，差别很大，标签上的数字只能当参考。
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