A cell recycle system was recommended
for corn wine fermentation using S. cerevisiae
M30, a flocculate yeast. Dried fibrous loofa sponge
was confirmed as capable of supporting A. aceti
WK cells, which adhered to the sponge surface
and could be used for vinegar production in an
STR. Using the semi-continuous process for corn
vinegar production, a charging rate of 30% for
filtered fresh corn wine was determined as the
optimum for vinegar production in a 50-liter STR.
An average acidity content of 4.1±0.1% was
observed during six cycles of fermentation within
40 d. Moreover, a shorter fermentation time was
recorded after the first two cycles. This indicated
that the A. aceti WK cells had successively adapted
to the semi-continuous conditions in the STR.
Additionally, results confirmed that loofa
sponge could be used for vinegar production in
both an airlift fermenter and STR. Such a use
supports the utilization of organic material for food
as well as the green concept of being environment
friendly, as the sponge can be easily and naturally
decomposed and used as bio-fertilizer. Further
study could investigate a suitable scale-up level
using loofa material, as well as considering other
organic fibrous materials