Reference Number: 9
Year: 2009
Link: Link to original paper
Health: Key Research Papers
Nutrition: Amino Acids | Bioactive peptides | Fibre | Minerals | Phytic acid | Resistant starch | Vitamins
Summary
Abstract
Use of sourdough is of expanding interest for improvement of flavour, structure and stability of baked goods. Cereal fermentations shows significant potential in the improvement and design of the nutritional quality and health effects of foods and ingredients. In addition to improving the sensory quality of whole grain, fibre-rich or gluten-free products, sourdough can also actively retard starch digestibility leading to low glycemic responses, modulate levels and bioaccessibility of bioactive compounds, and improve mineral bioavailability. Cereal fermentation may produce non-digestible polysaccharides, or modify accessibility of the grain fibre complex to gut microbiota. It has also been suggested that degradation of gluten may render bread better suitable for celiac persons.
The changes in cereal matrix potentially leading to improved nutritional quality are numerous. They include acid production, suggested to retard starch digestibility, and to adjust pH to a range which favours the action of certain endogenous enzymes, thus changing the bioavailability pattern of minerals and phytochemicals. This is especially beneficial in products rich in bran to deliver minerals and potentially protective compounds in the blood circulation. The action of enzymes during fermentation also causes hydrolysis and solubilisation of grain macromolecules, such as proteins and cell wall polysaccharides. This changes product texture, which may affect nutrient and non-nutrient absorption. New bioactive compounds, such as prebiotic oligosaccharides or other metabolites, may also be formed in cereal fermentations.
Significance of this study to the baker
This study presents an overview of the unique nutritional and sensory benefits of sourdough. The researchers note that sourdough can reduce starch digestibility, thereby resulting in a low-glycemic index. Not only can this keep you fuller for longer, but it also prevents blood sugar spikes, something associated with type-2 diabetes.
Moreover, the paper explores how fermentation with a sourdough starter can increase the bioavailability of minerals and phytochemicals. By doing so, the resultant bread is more nutritious. Lastly, the study notes that sourdough fermentation may form prebiotic compounds such as oligosaccharides. These can feed beneficial bacteria in the gut microbiome and fuel the production of essential short-chain fatty acids. Currently, large-scale clinical studies on sourdough health benefits are lacking, though the existing research on the health benefits is clearly summarised here.