Determination of anti-diabets effects and antioxidant bioaccessibility of different bread varieties

This study comprehensively examined the functional properties of various bread types, evaluating their effects on antioxidant activity, total phenolic content (TPC), and the inhibition of alpha-glucosidase and alpha-amylase enzymes. The findings revealed that the nutritional characteristics of bread types vary significantly depending on the grain used. In terms of specific volume, wheat bread exhibited the highest value at 3.20 cm³/g, while buckwheat bread had the lowest at 1.02 cm³/g. Baking loss was highest in oat bread at 13.10% and lowest in rye bread at 11.64%. These results indicate significant differences in how different grains behave during the baking process. When analyzing phenolic content, rye bread showed the highest levels in both free (0.57 mg GAE/g) and bound fractions (2.72 mg GAE/g). In terms of bioaccessible fractions, whole wheat bread stood out with the highest TPC at 4.11 mg GAE/g. These results highlight the distribution of phenolic compounds across different fractions in bread and how this varies with the type of grain. In antioxidant activity assessments, whole wheat bread demonstrated the highest DPPH radical scavenging capacity at 53.57 mmol TEAC/g. Buckwheat bread showed the strongest ABTS radical scavenging effect, with 4.99% in the free fraction and 18.15% in the bound fraction. In FRAP analysis, rye bread exhibited the highest antioxidant capacity with 32.89 mmol TEAC/g in the free fraction and 15.64 mmol TEAC/g in the bound fraction. In alpha-glucosidase inhibition tests, buckwheat bread emerged as the most effective, with the lowest IC50 values in both the free (0.140 mg) and bound fractions (0.0315 mg). For alpha-amylase inhibition, rye bread showed the highest inhibition rate at 43.97% in the free fraction. In conclusion, this study demonstrates that the potential health effects of different bread types vary greatly depending on the type of grain and the bioavailability of its components. Buckwheat and rye breads, in particular, showed strong performances in terms of antioxidant and antidiabetic effects, indicating that they may offer significant health benefits as functional foods. These findings provide valuable insights for the selection and consumption of different bread types.