This study aimed to identify optimal recipes and conditions for creating fine-ground wholegrain flour sourdoughs and to evaluate the quality of wheat bread made with 20% of these sourdoughs. Sourdoughs were prepared from wholegrain flours of wheat (WWF), rye (WRF), spelt (WSF), barley (WBF), buckwheat (WBWF), and sorghum (WSGF) using a Fermentor Diosna & IsernHäger AF Compact 100 HC with a wheat and rice starter culture. The sourdough fermentation was conducted over 20 hours at 30°C. Quality assessments of the sourdoughs included pH measurement, total titratable acidity (TTA), and volatile compound analysis via GC-MS. Bread was baked with these sourdoughs using a single-phase method in a Home Bakery ETA 2147 Duplica Vital, applying a 3-hour classic program in a controlled laboratory setting at the Department of Carbohydrates and Cereals, UCT, Prague. The control flour for baking was a special wheat flour type 530 (SWF). Post-baking, bread weight, volume (using the mustard seed displacement method), specific volume, and crumb hardness (measured by penetrometer) were recorded.

The selected sourdough yields were 250% for WWF, WSF, WBWF, and WSGF; 280% for WBF; and 300% for WRF. The dough yield for baking was standardized at 165%. GC-MS analysis identified 24 volatile compounds, predominantly alcohols and organic acids, with lesser amounts of esters, aldehydes, terpenes, furans, and ketones. Bread containing WWF sourdough exhibited the highest weight and the softest crumb, while control (SWF) bread had the lowest weight. Both WWF and SWF breads showed the highest volume. In contrast, bread with WSGF sourdough had the hardest crumb. These findings suggest that WWF sourdough yields the most favorable bread characteristics among the tested flours.