A carregar...
Publicação
Problems in the use of benzoic acid for estimating the internal pH of yeasts
| Nome: | Descrição: | Tamanho: | Formato: | |
|---|---|---|---|---|
| 160.41 KB | Adobe PDF |
Orientador(es)
Resumo(s)
Some yeasts have the peculiar ability to grow in the
presence of weak acids at rather low pH.
These conditions are predominant in preserved
foods and beverages such as fruit concentrates,
juices, wine, where these yeasts are responsible
for spoilage. The main preservatives currently
utilized by food industries are sorbic, propionic,
benzoic acids and SO2. It is usually assumed
that weak acids diffuse through the plasma membrane
in the undissociated form. In the cytoplasm, where
the pH is higher, dissociation occurs resulting in
accumulation of the lipid-insoluble anion and internal
acidification. This is probably a very general mechanism
of preventing microbial growth in foods.