И так. Меня заинтересовала эта тема и было принято решение собрать информацию по брожению.
Итак, ФАК действительно восстанавливаестя в диол. Но почему то сразу диол из БА никто не получает. Почему? Загадка. Так что брожение БА прямо в диол не миф
https://pubs.acs.org/doi/pdf/10.1021/ed072p277

1-Phenylpropane-1,2-diol, PhCHOH.CHOH.CH3, was originally isolated in two
racemic forms, ~-, m.p. 57~ and fl-, m.p. 93 ~ from 1,2-dibromo-l-phenylpropane.
Both forms gave phenylacetone when boiled with dilute sulphuric acid, and phenyl-
methylglyoxal when oxidised with nitric acid (Zincke and K. Zahn, Ber., 1910, 43,
849). Optically active forms have been obtained from inactive benzoylmethylmethanol
by reduction with fermenting yeast (C. Neuber9 and W. Komarewsky, Biochem. Z.,
1927, 182, 287; F. yon Falkenhausen, ibid., 1930, 219, 242, 24

It is well known that the reduction of 1-phenylpropane-1,2-dione 47 medi-
ated by baker’s yeast gives (1R,2S)-1-phenylpropanediol 50 in excellent yield
and ee,41 through a mechanism involving consecutive reactions where both
Cao bonds are reduced. 42 as a consequence, two interesting reaction inter-
mediates were detected (scheme 10.10).