Influence of novel fructans produced by selected acetic acid bacteria on the volume and texture of wheat breads

Development of novel sourdoughs with in situ formed exopolysaccharides from acetic acid bacteria

“…Recently, several AAB strains have been shown to produce effective EPS with a positive influence on the quality and staling of wheat breads [14]. In this study, bacterial growth and the in situ formation of EPS (fructan) from sucrose in dough fermentations with K. baliensis and N. chiangmaiensis were investigated.…”

“…As both strains turned out to produce the highest EPS amount in situ, they might be promising strains for future work. It has been shown that the addition of EPS from AAB has desirable technological effects already at a level of 1 %, whereby lower levels have not been tested [14]. Furthermore, it has been shown that a relation between molecular structure and functionality of EPS exists, and these fructans are of uniquely high molecular weight and exert strong textural effects in breads [31].…”

“…In our study, two to three times more EPS were obtained with N. chiangmaiensis and K. baliensis. In baking trials performed by Jakob et al [14], EPS isolated from K. baliensis and N. chiangmaiensis were identified as having the most positive effect on bread volume and staling. As both strains turned out to produce the highest EPS amount in situ, they might be promising strains for future work.…”

“…During their formation, the osidic bond of sucrose is cleaved either by a fructosyl-or glycosyl-transferase and the energy set free enables transfer of the sugar residue via a covalent glycosyl-enzyme intermediate [12,13]. Recently, it was shown that fructans of several acetic acid bacterial strains cause an increased volume, clear softening effect and retarded staling of fresh wheat breads during 1-week storage [14]. Acetic acid bacteria (AAB) are gram-negative, obligate aerobic and ellipsoidal to rodshaped bacteria, whose common feature is the incomplete oxidation of a wide range of alcohols and sugars via alternative pathways [15,16].…”

Structural analysis of fructans produced by acetic acid bacteria reveals a relation to hydrocolloid function

“…We recently demonstrated that fructans isolated from the fructan-overproducing AAB strains Gluconobacter frateurii, Gluconobacter cerinus, Kozakia baliensis and Neoasaia chiangmaiensis significantly increase volume, reduce crumb hardness and retard staling of wheat breads (Jakob, Steger, & Vogel, 2012). Furthermore, we observed different effects on the volume and texture when adding fructose polymers produced by these selected AAB species.…”