Background: The use of plant-based additives with high nutritional value in the bakery technologies is an important trend in the development of functional foods.

Objective: The aim of this study was to develop the technology of wheat and rye breads as functional foods with antioxidant properties using plant-based by-products of oil industry. The inclusion of additives such as wheat germ and rosehip cake meal was carried out by partially replacing flour in the wheat and rye bread formulation in the range of 3-20% (depending on the type of additive).

Methods: The total antioxidant capacity (TAC) and the total polyphenol content (TPC) of the samples were determined by galvanostatic coulometry with electrogenerated bromine as a model oxidant and a spectrophotometric Folin—Ciocalteu method, respectively. The TAC and TPC values of the samples were classified using multivariate statistical methodology techniques such as cluster and principal component analysis.

Results: It was found that the inclusion of plant-based additives increased both the antioxidant properties of TAС and TPС of both wheat and rye bread. The greatest effect of an increase in TAС at the level of 10% was observed in samples of wheat bread with the inclusion of rosehip meal. The TAC of rye bread samples was higher than wheat bread samples. There is a positive correlation between TAC and TPC values for samples with a Pearson correlation coefficient of 0.898. This confirms the possibility of using TAC as a preliminary characteristic of the antioxidant properties of samples. The use of cluster analysis methodology allowed us to classify the effect of additives on increasing antioxidant properties in the form of two clusters. The results of multivariate analysis were discussed.

Conclusion: The inclusion of wheat germ flour and rosehip cake in the bread formulation develops a functional food with increased antioxidant properties.