The addition of sourdough fermented with lactic acid bacteria synthesizing organic acids and oligo- and exopolysaccharides (EPS) from sucrose enhances texture, nutritional value, shelf life, and machinability of wheat, rye, and gluten-free bread. This study compared acetate, mannitol, and oligosaccharide formation of EPS-producing strains of Weissella and Leuconostoc spp. to the traditional sourdough starter Lactobacillus sanfranciscensis. In broth, Leuconostoc strains generally formed acetate and mannitol, whereas Weissella produced only small amounts of acetate and no mannitol in the presence of sucrose. In the presence of sucrose and maltose, Weissella and Leuconostoc strains synthesized glucooligosaccharides and EPS. Strains of Weissella were employed as starter cultures for wheat and sorghum sourdough and formed 0.8-8 g kg(-1) EPS and gluco-oligosaccharides but only low amounts of acetate and mannitol. In contrast, the formation of EPS from sucrose led to the production of high amounts of acetate and mannitol by L. sanfranciscensis LTH 2950 in wheat sourdough. This study indicates that Weissella strains are suitable starter cultures for wheat and sorghum sourdoughs and efficiently produce gluco-oligosaccharides and EPS.

The use of sourdough improves the quality and increases the shelf life of bread. The positive effects are associated with metabolites produced by lactic acid bacteria (LAB) during sourdough fermentation, including organic acids, exopolysaccharides (EPS), and enzymes. EPS formed during sourdough fermentation by glycansucrase activity from sucrose influence the viscoelastic properties of the dough and beneficially affect the texture and shelf life (in particular, starch retrogradation) of bread. Accordingly, EPS have the potential to replace hydrocolloids currently used as bread improvers and meet so the consumer demands for a reduced use of food additives. In this review, the current knowledge about the functional aspects of EPS formation by sourdough LAB especially in baking applications is summarized.

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bThis study determined the effect of feed fermentation with Lactobacillus reuteri on growth performance and the abundance of enterotoxigenic Escherichia coli (ETEC) in weanling piglets. L. reuteri strains produce reuteran or levan, exopolysaccharides that inhibit ETEC adhesion to the mucosa, and feed fermentation was conducted under conditions supporting exopolysaccharide formation and under conditions not supporting exopolysaccharide formation. Diets were chosen to assess the impact of organic acids and the impact of viable L. reuteri bacteria. Fecal samples were taken throughout 3 weeks of feeding; at the end of the 21-day feeding period, animals were euthanized to sample the gut digesta. The feed intake was reduced in pigs fed diets containing exopolysaccharides; however, feed efficiencies did not differ among the diets. Quantification of L. reuteri by quantitative PCR (qPCR) detected the two strains used for feed fermentation throughout the intestinal tract. Quantification of E. coli and ETEC virulence factors by qPCR demonstrated that fermented diets containing reuteran significantly (P < 0.05) reduced the copy numbers of genes for E. coli and the heat-stable enterotoxin in feces compared to those achieved with the control diet. Any fermented feed significantly (P < 0.05) reduced the abundance of E. coli and the heat-stable enterotoxin in colonic digesta at 21 days; reuteran-containing diets reduced the copy numbers of the genes for E. coli and the heat-stable enterotoxin below the detection limit in samples from the ileum, the cecum, and the colon. In conclusion, feed fermentation with L. reuteri reduced the level of colonization of weaning piglets with ETEC, and feed fermentation supplied concentrations of reuteran that may specifically contribute to the effect on ETEC.T he combined stress of weaning and movement to a different environment increases the potential for poor growth performance, nutrient malabsorption, and diseases in piglets (1-3). Diarrhea caused by enterotoxigenic Escherichia coli (ETEC) is a major disease of weaning piglets (4). ETEC establishes infection by specific fimbria mediating intestinal attachment and colonization (4-7). Following colonization, ETEC produces enterotoxins that induce watery diarrhea (8, 9). Control of ETEC infections of weanling piglets is currently achieved by antibiotics (10). The use of antibiotics in animal production, however, selects for antibiotic-resistant intestinal microbiota and favors the transfer of antibiotic resistance genes from livestock microbiota to human pathogens (7). Consequently, antimicrobial growth promoters have been banned in several jurisdictions (11), challenging the livestock industry to replace feed antibiotics without compromising animal performance or animal health.Probiotic bacteria, prebiotics, organic acids, or antiadhesive glycans were proposed to replace feed antibiotics in pig production for improved control of ETEC (4, 6). Organic acids were shown to reduce postweaning diarrhea in pigs (12). Probiotics also decreased the inc...

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Aims: The growing interest of governments and industry in developing healthy and natural alternative foods and beverages that will fulfil the consumer drive towards a healthy lifestyle and clean-label, natural diet has led to an increase in traditional lactic acid bacteria fermentation research. In particular, this research aims to address the organoleptic modulation of beverages using in situ-produced bacterial polysaccharides. Methods and Results: Weissella cibaria MG1 is capable of producing exopolysaccharides (dextran) and oligosaccharides (glucooligosaccharides) during sucrose-supplemented barley-malt-derived wort fermentation. Up to 36Á4 g l À1 of dextran was produced in an optimized system, which improved the rheological profile of the resulting fermentate. Additionally, small amounts of organic acids were formed, and ethanol remained below 0Á5% (v/v), the threshold volume for a potential health claim designation. Conclusions:The results suggest that the cereal fermentate produced by W. cibaria MG1 could be potentially used for the production of a range of novel, nutritious and functional beverages. Significance and Impact of the Study: Using conventional raw materials and traditional processes, novel LAB-fermented beverages can be produced representing an innovative mechanism towards fulfilling the aim to decrease government and personal costs as well as potentially ameliorating consumer lifestyle regarding dietary-related disease.

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