Application of a sourdough type-II fermentation model to gelatinized legume flours: Starter robustness, technological and nutritional implications, potential of the bread and pasta fortification

Abstract

This study highlights the benefits of combining gelatinization with Type-II sourdough fermentation for improving lentil and chickpea flours. The fermentation process effectively reduces anti-nutritional factors while enhancing the nutritional, technological, and sensory qualities of the resulting products. By employing a back-slopping technique typical of Type-I sourdough, different propagation steps were analyzed. The results showed that sourdough fermentation positively influenced the biochemical properties of fortified foods, leading to improved protein digestibility and a lower predicted glycemic index. However, after the fifth propagation cycle, there was a decline in the dominance of starter cultures, which negatively impacted the concentration of free amino acids and protein digestibility in the breads. To ensure consistent quality and economic viability in industrial applications, the study suggests using freeze-drying or refrigeration to stabilize Type-II legume sourdough as a natural starter. This method, combined with five cycles of back-slopping propagation, could provide a robust solution for maintaining the nutritional and functional properties of fermented products.