Aerobic submerged fermentation by acetic acid bacteria for vinegar production: Process and biotechnological aspects

Abstract

Strictly aerobic acetic acid bacteria (AAB) have a long history of use in fermentation processes, and the conversion of ethanol to acetic acid for the production of vinegar is the most wellknown application. At the industrial scale, vinegar is mainly produced by submerged fermentation, which refers to an aerobic process in which the ethanol in beverages such as spirits, wine or cider is oxidized to acetic acid by AAB. Submerged fermentation requires robust AAB strains that are able to oxidize ethanol under selective conditions to produce high-titer acetic acid. Currently submerged fermentation is conducted by unselected AAB cultures, which are derived from previous acetification stocks and maintained by repeated cultivation cycles. In this work, submerged fermentation for vinegar production is discussed with regard to advances in process optimization and parameters (oxygen availability, acetic acid content and temperature) that influence AAB activity. Furthermore, the potential impact arising from the use of selected AAB is described. Overcoming the acetification constraints is a main goal in order to facilitate innovation in submerged fermentation and to create new industry-challenging perspectives.

Simultaneous production of acetic and gluconic acids by a thermotolerant Acetobacter strain during acetous fermentation in a bioreactor

“…A comparative study of acetic acid productivity of wild-type AAB used for ethanol oxidation was reported by Gullo et al (39). Overall, mesophilic strains exhibited a significant acetic acid yield with respect to thermotolerant species (39).…”

“…Overall, mesophilic strains exhibited a significant acetic acid yield with respect to thermotolerant species (39). However, thermo-adapted strains (which stably perform efficient acetous fermentation at high temperatures) were obtained after a number attempts to isolate thermotolerant mutants (39,40).…”

Bio-produced Acetic Acid: A Review

“…It consists of a stainless steel equipped with aerator, charging pump, alkalograph, cooling water valve, thermostat cooling, rotameter, cooling coil, air line, air exhaust line and defoamer [11,19,29]. Aerator is the most specific part of Acetator, since this special impeller is self-aspirating, and through effective dispersion provide the highest oxygen transfer, described detail elsewhere [27].…”

Production of Dry Extract Lipase from Pseudomonas Aeruginosa by the Submerged Fermentation Method in Palm Oil Mill Effluent

“…After 96 hours above, culture growth decreased and reached the death phase because the environment no longer supported any growth (Yates & Smotzer, 2007), such as the lack of nutrients and oxygen in the medium. In submerged fermentation, consumption of oxygen is proportional to the conversion of the substrate into the product (Gullo et al, 2014).…”