Effect of Spontaneous Rye, Wheat, and Mixed Rye-Wheat Sourdoughs on Quality, Aroma, and Acrylamide Content of Homemade and Small Bakeries Bread

This study aimed to assess the quality characteristics, including acrylamide level and volatile compound (VOC) profile, in wheat bread made without industrial additives using varying quantities (5%, 10%, and 15%) of spontaneous rye, rye/wheat mixed, and wheat sourdoughs. The lowest pH was observed in wheat-based sourdough samples (3.91). The highest LAB count was found in rye/wheat mixed sourdough samples (8.50 log(1)(0) CFU/g). Bread porosity was influenced by the type of sourdough (p < 0.001) while the type and quantity of sourdough used significantly affected the bread moisture content (p < 0.001 and p = 0.033, respectively). In all cases, the addition of sourdough to the main bread formula reduced the shape coefficient and increased the acrylamide content in the bread. The highest concentration of acrylamide was found in breads prepared with 5%, 10%, and 15% rye/wheat mixed sourdough, as well as with 15% wheat sourdough (averaging 17.5 mu g/kg). The main VOC in bread samples were ethanol and 3-methyl-1-butanol. A strong correlation was found between acrylamide concentration and certain VOC, for example, 1-butanol (r = 0.621, p < 0.001), butanoic acid (r = 0.722, p < 0.001), gamma-amylbutyrolactone (r = 0.644, p < 0.001), phenylethyl alcohol (r = -0.841, p < 0.001), and octanoic acid (r = -0.715, p < 0.001). To conclude, acrylamide formation in breads with spontaneous sourdough, particularly wheat or rye/wheat, was enhanced but did not exceed the benchmark levels set by the European Commission.