title: Acetification of rice wine by Acetobacter aceti using loofa sponge in a low-cost reciprocating shaker.
abstract: OBJECTIVE
  To maximize acetification rate (ETA) by adsorption of acetic acid bacteria (AAB) on loofa sponge matrices (LSM).
  
  
  RESULTS
  AAB were adsorbed on LSM, and the optimal shaking rate was determined for maximized AAB growth and oxygen availability. Results confirm that the 1 Hz reciprocating shaking rate with 40% working volume (liquid volume 24 l, tank volume 60 l) achieved a high oxygen transfer coefficient (k(L)a). The highest ETA was obtained at 50% (w:v) LSM-AAB:culture medium at 30 ± 2°C (P ≤ 0·05). To test process consistency, nine sequential acetification cycles were run using LSM-AAB and comparing it with no LSM. The highest ETA (1·701-2·401 g l(-1) d(-1)) was with LSM-AAB and was associated with the highest biomass of AAB, confirmed by SEM images.
  
  
  CONCLUSIONS
  Results confirm that LSM-AAB works well as an inert substrate for AAB. High oxygenation was maintained by a reciprocating shaker. Both shaking and LSM were important in increasing ETA.
  
  
  CONCLUSIONS
  High cell biomass in LSM-AAB provides good conditions for higher ETAs of quick acetification under adequate oxygen transfer by reciprocating shaker. It is a sustainable process for small-scale vinegar production system requiring minimal set-up cost.
authors.affiliation: Fermentation Technology Division, Faculty of Agro-Industry, King Mongkut's Institute of Technology Ladkrabang, Ladkrabang, Bangkok, Thailand.
authors.forename: W
authors.initials: W
authors.lastname: Krusong
authors.forename: S
authors.initials: S
authors.lastname: Tantratian
mesh_terms: D019342:Acetic Acid / Q000378:metabolism*; D000091:Acetobacter / Q000254:growth & development / Q000378:metabolism* / Q000648:ultrastructure; D000327:Adsorption; D003470:Culture Media; D005285:Fermentation; D029776:Luffa; D012275:Oryza; D014920:Wine
chemical_list: D003470:Culture Media; D019342:Acetic Acid
keywords: acetification rate; loofa sponge matrices; oxygen transfer; reciprocating shaker system; rice wine