The total polyphenolic content and the antioxidant activity have been analyzed in ground beans of green, light, medium and dark roasted coffee by UV-VIS spectrometry. Water coffee extracts showed the highest levels of polyphenols in green and light roasted coffees where the total polyphenolic content (TPC) ranged from 49.19 ± 0.70 to 74.05 ± 0.28 and from 59.79 ± 1.45 to 38.34 ± 1.26 g GAE.kg-1, respectively. In medium roast samples it ranged from 43.90 ± 3.07 to 74.05 ± 0.28g GAE.kg-1 and in dark roast from 37.44 ± 0.63 to 47.41 ± 0.69 g GAE.kg-1. The total antioxidant capacity (TAC) reached the highest values (DPPH inhibition ranging from 69.08 ± 1.33% to 78.55 ± 0.89%) in light roasted coffees. Dark roasted coffees showed both the lowest content of polyphenols as well as the total antioxidant capacity. In case of TPC, statistically significant differences (P˂0.001) have been identified between green coffee and other roasted degrees. Also, dark coffee showed statistically noticeable differences (P˂0.001) in TPC in relation to other roasted stages. Statistically important difference (P˂0.001) has been discovered between the total antioxidant capacity of dark roasted coffee and other roasting levels. The results demonstrated that roasting process affects both the oxidative activity as well as polyphenolic content.

中文翻译：

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烘焙对咖啡中总多酚和抗氧化活性的影响。

通过UV-VIS光谱法分析了绿色，浅色，中度和深色焙炒咖啡的咖啡豆中的总多酚含量和抗氧化活性。水生咖啡提取物在绿色和浅色烘焙咖啡中显示出最高的多酚含量，其中总多酚含量（TPC）分别为49.19±0.70至74.05±0.28和59.79±1.45至38.34±1.26 g GAE.kg-1。在中等烘烤样品中，GAE.kg-1为43.90±3.07至74.05±0.28g GAE.kg-1；对于黑暗烘烤样品，其为37.44±0.63至47.41±0.69 gGAE.kg-1。在轻度烘焙咖啡中，总抗氧化剂容量（TAC）达到最高值（DPPH抑制范围为69.08±1.33％至78.55±0.89％）。深色烘焙咖啡显示出最低的多酚含量和总抗氧化能力。如果是TPC，在生咖啡和其他烘焙度之间已发现统计学上的显着差异（P˂0.001）。同样，黑咖啡与其他烘焙阶段相比，TPC在统计学上也有显着差异（P˂0.001）。在深色烘焙咖啡的总抗氧化能力与其他烘焙水平之间发现了具有统计学意义的差异（P˂0.001）。结果表明，焙烧过程影响氧化活性以及多酚含量。已在深色烘焙咖啡的总抗氧化能力与其他烘焙水平之间发现了001）。结果表明，焙烧过程影响氧化活性以及多酚含量。已在深色烘焙咖啡的总抗氧化能力与其他烘焙水平之间发现了001）。结果表明，焙烧过程影响氧化活性以及多酚含量。