A new pilot plant scale acetifier designed for vinegar production in Sub-Saharan Africa

A novel thermotolerant strain Acetobacter senegalensis sp. nov. (CWBI-B418T) isolated in Senegal from mango fruit, previously freeze-dried and conserved at 4 °C under vacuum packaging was successfully rehydrated into an acetifying medium. It was used as an inoculum culture and then applied into a new pilot plant scale acetifier (300 L) for vinegar production. This latter was specifically designed to produce a high volume and quality of vinegar in Sub-Saharan Africa at fermentation temperature of 35 °C. Several semi-continuous cycles of acetic acid fermentations were carried out. The behaviour of substrate and product concentrations, population of bacteria into the reactor was analysed as well as the evolution of acidity, acetification rates and stoichiometric yields. Operation with this novel bioreactor allowed achieving 8% (v/v) of acetic acid concentration at 35 °C.