How might Schwann's observations about embryos have affected the theory of spontaneous generation?

The theory of spontaneous generation exclaimed that living organisms could arise from non-living matter.

Schwann affected this theory by demonstrating that fermentation required the presence of yeasts to start and that was not caused by oxygen as was speculated.

Schwann concluded by his experiments that sugar was converted to alcohol as part of an biological process based on the action of a living organism - the yeast.