Influence of cold plasma treatment on the bioaccessibility of phenolic compounds in apicultural products

BACKGROUND: Apicultural products are natural sources of phenolics with significant biological activity, yet limited information exists on the impact of green processing technologies on their stability and bioaccessibility. The present study, for the first time, applied cold plasma (CP) treatment, comprising an emerging non-thermal and environmentally friendly technique, to propolis, bee pollen, bee bread and beeswax, aiming to evaluate its influence on phenolic content and bioaccessibility under simulated gastrointestinal conditions. RESULTS: Ultra-performance liquid chromatography electrospray ionization tandem mass spectrometry analysis identified major phenolics as 3,4-dimethoxycinnamic acid and pinocembrin in propolis and beeswax, luteolin and pinocembrin in bee pollen, and 4-hydroxybenzoic acid and kaempferol in bee bread. CP treatment induced matrix- and time-dependent changes in phenolics. In undigested samples, short and moderate treatments (5-10 min) produced variable responses, with increases in total flavonoids (5-60%) and phenolic acids (11-86%) in some matrices, whereas reductions were also observed. Prolonged exposure (20 min) more frequently resulted in reductions (8-51%), suggesting oxidative degradation. CP affected phenolic bioaccessibility in a matrix-dependent manner. Bioaccessibility of total phenolics increased from 13% to 16-19% in propolis, reached up to 65% in bee pollen, and increased from 73% to 94% in bee bread, whereas beeswax showed the most pronounced response, rising from 47% to 103%. Similarly, total flavonoid bioaccessibility improved from 29% to 66% in bee pollen and from 15% to 49% in bee bread. CONCLUSION: These results indicate that CP effects on phenolic content and bioaccessibility depend on matrix, treatment conditions, and analytical method, highlighting the need for product-specific optimization. © 2026 Society of Chemical Industry.