VINEGAR PRODUCTION
•as old as wine production.
French words vin ( wine ) and aigre ( sour ).
It should contain > 4 % acetic acid in USA ( FDA) and Turkey, > 5% acetic acid in EC.
•It is mainly used as flavoring agent, in food pickling and in medicine.
•Vinegar is produced by oxidative ( aerobic ) fermentation of ethanol in to acetic acid by Acetobacter species.( ie aceti)
•C2H5OH + ½ O2 CH3CHO (acetaldehyde ) + H2O
• + H2O
• H2C – CH(OH)2 (hyd acetaldehyde ) CH3COOH ( a acid) + H2O
• +1/2 O2 acetaldehyde dehydrogenase
•DH0 = -483 kj = - 118 kcal.
Conversion yield of ethanol to acetic acid: 95-98 %.

During process 2-5 % of acetic acid may be over
oxidized ( undesired ) to CO2 and H2O.

stop oxidative fermentation before ethanol is completely depleted to prevent over oxidation.

leave wine ( in a plate ) open to atmosphere, observe a film formed over the surface it is made of acetic acid bacteria
( in Turkish it is called as sirke anası ).






Dosya türü: ppt

Şifre: www.forumfood.net