Orange vinegar production by semicontinuous fermentation in a laboratory scale

Abstract

Vinegar is the product obtained from wine acetic acid fermentation and is mainly produced by semicontinuous operation, which consists in developing successive discontinuous acetification cycles. Citric vinegars and wines are typical products with regional qualities. The aim of the present work was to establish the optimal values for the substrate loading proportion (wine/vinegar) at two levels (40 % and 60 %) in order to obtain orange vinegar in semicontinuous submerged culture. The results were evaluated in terms of acetification rate and fermentation yield. Experiments were carried out in duplicate. Stirring speed, air supply and temperature were maintained constant with values of 600 rpm, 0.4 vvm and 30°C respectively. It was demonstrated that the loading proportion did not affect significantly the responses (α=0.05) at both levels evaluated. It is feasible to develop a semicontinuous acetification process with a 60 % loading proportion and in this way, obtain greater orange vinegar volumes.