Chu Rui, Uaila Eulalia, Ismail Tariq, Lazarte Claudia E
Division of Food and Pharma, Department of Process and Life Science Engineering, Lunds Tekniska Högskola, Lund University, 22100 Lund, Sweden.
Department of Chemistry, Science Faculty, Eduardo Mondlane University, Maputo 257, Mozambique.
Foods. 2024 Jul 30;13(15):2413. doi: 10.3390/foods13152413.
Quinoa ( Willd.) is a pseudocereal originally grown in the Andean region of South America. This study focused on investigating the changes in phenolic profile and antioxidant capacity in white and red quinoa varieties after short-term fermentation with 299v. During fermentation, pH and lactic acid formation were monitored every three hours until pH was below 4.6. The quinoa phenolic profile was quantified via LC-UV-MS. Total polyphenol content (TPC) and total antioxidant capacity (DPPH and FRAP) were determined via spectrophotometric methods. The findings showed that fermentation resulted in a significant increase ( < 0.001) in TPC from 4.68 to 7.78 mgGAE·100 g for the white quinoa and from 5.04 to 8.06 mgGAE·100 g for the red quinoa variety. Gallic acid was the most abundant phenolic acid detected in unfermented quinoa samples (averaging 229.5 μg·g). Fermented white quinoa showed an 18-fold increase in epicatechin, while catechin was found only in fermented red quinoa (59.19 μg·g). Fermentation showed a significantly positive impact on the iron-reducing antioxidant capacity (FRAP) of quinoa ( < 0.05). Red quinoa had a higher FRAP antioxidant capacity than the white variety; a similar trend was observed with the DPPH assay. There was a significant correlation (r > 0.9, < 0.05) between TPC and antioxidant capacity. In conclusion, short-time lactic fermentation effectively increased phenolic content and antioxidant capacity in both quinoa varieties. Overall, red quinoa showed higher polyphenol content and antioxidant capacity compared to the white variety.
藜麦（Chenopodium quinoa Willd.）是一种原产于南美洲安第斯地区的假谷物。本研究聚焦于调查299v短期发酵后白藜麦和红藜麦品种中酚类物质概况及抗氧化能力的变化。在发酵过程中，每三小时监测一次pH值和乳酸形成情况，直至pH值低于4.6。通过液相色谱 - 紫外 - 质谱联用（LC - UV - MS）对藜麦的酚类物质概况进行定量分析。通过分光光度法测定总多酚含量（TPC）和总抗氧化能力（DPPH和FRAP）。研究结果表明，发酵使白藜麦的TPC从4.68毫克没食子酸当量·100克显著增加至7.78毫克没食子酸当量·100克（P < 0.001），红藜麦品种从5.04毫克没食子酸当量·100克增加至8.06毫克没食子酸当量·100克。没食子酸是未发酵藜麦样品中检测到的最丰富的酚酸（平均229.5微克·克）。发酵后的白藜麦表儿茶素增加了18倍，而儿茶素仅在发酵后的红藜麦中被发现（59.19微克·克）。发酵对藜麦的铁还原抗氧化能力（FRAP）有显著的正向影响（P < 0.05）。红藜麦的FRAP抗氧化能力高于白藜麦品种；DPPH测定也观察到类似趋势。TPC与抗氧化能力之间存在显著相关性（r > 0.9，P < 0.05）。总之，短时间乳酸发酵有效提高了两个藜麦品种的酚类含量和抗氧化能力。总体而言，与白藜麦品种相比，红藜麦表现出更高的多酚含量和抗氧化能力。
