Effect of honey supplementation on sourdough: Lactic acid bacterial performance and gluten microstructure

- Honey supplementation of sourdough increased LAB population.
- The presence of honey did not modified organic acid production by LAB.
- Honey induced the development of a closed gluten network in dough.
- The acidifying activity of LAB lead to the generation of gluten fibrils in dough.
- The high acidity of P. pentosaceus prevented the effect of honey on gluten network.

In the present study we evaluate the effect of honey on the growth and fermentative ability of two sourdough fermenting lactic acid bacteria (LAB), Pediococcus pentosaceus and Lactobacillus fermentum, and the impact that honey and LAB have on gluten microstructure. Growth kinetics and fermentative analyses were carried out through cell viability and potenciometry assays, respectively. Honey supplementation of sourdough increased LAB population. L. fermentum exhibited a higher growth rate, while P. pentosaceus was more acidifying. The fermentative profile of LAB was not altered by the presence of honey. The microstructure analyses were performed through scanning electron microscopy (SEM) and revealed that the microstructure of dough was modified by the fermenting activity of LAB, being involved in the development of gluten fibrils. In addition, honey induced changes in the microstructure of those dough whose pH value were higher than 4, disclosing a strong association between protein subunits.