Kiedy cydr jest JUŻ dobry a po jakim czasie być przestaje.

[tibek]

Wszystkie saccharomyces cerevisiae przetwarzają, ale robią to w różnym tempie - nie mają mechanizmu aktywnego transportu kwasu jabłkowego przez błonę, tylko dyfuzja, w cydrach refermentowanych w butelce mają na to czas.
Za handbook of enology:

Saccharomyces cerevisiae partially degrades must
malic acid (10–25%) during alcoholic fermentation.
Different strains degrade varying amounts
of this acid, and degradation is more significant
when the pH is low. Alcoholic fermentation
is the principal pathway degrading malic acid.
The pyruvic acid resulting from this transformation
is decarboxylated into ethanal, which is then
reduced to ethanol. The malic enzyme is responsible
for the transformation of malic acid into
pyruvic acid (Figure 2.19). This oxidative decarboxylation
requires NAD+ (Fuck and Radler,
1972). This maloalcoholic fermentation lowers
wine acidity significantly more than malolactic
fermentation.