Combined Effect of Sourdough Lactic Acid Bacteria and Additives on Bread Firmness and Staling

Abstract

The effect of various sourdoughs and additives on bread firmness and staling was studied. Compared to the bread produced with Saccharomyces cerevisiae 141, the chemical acidification of dough fermented by S. cerevisiae 141 or the use of sourdoughs increased the volume of the breads. Only sourdough fermentation was effective in delaying starch retrogradation. The effect depended on the level of acidification and on the lactic acid bacteria strain. The effect of sourdough made of S. cerevisiae 141-Lactobacillus sanfranciscensis 57-Lactobacillus plantarum 13 was improved when fungal alpha-amylase or amylolytic strains such as L. amylovorus CNBL1008 or engineered L. sanfranciscensis CB1 Amy were added. When pentosans or pentosans, endoxylanase enzyme, and L. hilgardii S32 were added to the same sourdough, a greater delay of the bread firmness and staling was found. When pentosans were in part hydrolyzed by the endoxylanase enzyme, the bread also had the highest titratable acidity, due to the fermentation of pentoses by L. hilgardii S32. The addition of the bacterial protease to the sourdough increased the bread firmness and staling.

Development of sourdough fermented date seed for improving the quality and shelf life of flat bread: study with univariate and multivariate analyses

“…This might be due to the fact that lactic acid bacteria increase metabolic activity of baker's yeast (Gobbetti et al 1995). Similar results were observed in Italian (Corsetti et al 1998) and Greek (Paramithiotis et al 2006) sourdoughs.…”

“…The application of sourdough has been reported to either improve (Crowley et al 2002) or decrease bread volume (Barber et al 1992); type of influence being dependent on the acidification rate obtained and on the microbial strains utilized. Positive influence of sourdough on volume might be due to various factors: (1) heterofermentative lactic acid bacteria have been reported to increase metabolic activity of baker's yeast (Gobbetti et al 1995) and thus produce more carbon dioxide for leavening; (2) appropriate acidity might enhance the ability of gluten to (Gobbetti et al 1995) (3) accumulation of water soluble pentosans may increase volume as a result of altered water distribution (Corsetti et al 1998). According to our results, utilization of fermented pulverized date seed improves protein network (enhanced CO 2 retention).…”

“…On the other hand, several studies provide evidence that exo-polysaccharides produced by sourdough LAB have the potential to improve bread texture and shelf life (Arendt et al 2007). Starch molecules can be affected by enzymes produced by LAB, causing a variation in the retrogradation properties of the starch, which slows the rate of staling (Corsetti et al 1998). Additionally, the acidic conditions and proteases associated with sourdough play a role in reducing the staling rate of bread (Arendt et al 2007).…”

Development of a method for the direct fermentation of semolina by selected sourdough lactic acid bacteria

“…The Chroma Meter CR-400 (Minolta, Osaka, Japan) was used for colour determination by the Hunter's scale parameters (L*, a* and b*) measured on crust (four points) and crumb of the central slices (three points). The hardness of crumb was determined by means of the Instron-5564 (Instrom Corp., Canton, MA) following the method reported by Corsetti et al (2000).…”

“…In general, the raw materials, the microbiota developing during the fermentation process and the technological parameters applied during bread making affect consistently the characteristics of the final products (Corsetti et al, 2000). In particular, the microbial composition of sourdough plays a major role during fermentation (De Vuyst and Neysens, 2005).…”