They were the sort of thing which required fermentation to render them effective.

它们那种需要发酵才能发挥作用的东西。

Indeed, given that microgravity and the high levels of radiation in space might disrupt the microbial interactions needed to make this process happen, it has always been unclear if fermentation was even possible in space.

事实上， 考虑到微重力和太空的高辐射水平可能会破坏发酵过程所需的微生物相互作用，发酵在太空否可行一未知数。

That's what leavening agents do, is they take air and they expand it and make it the cake.

这就发酵剂的作用，它们吸收空气并使其膨胀，从而形成蛋糕。