Folin-Ciocalteu法测定苹果醋饮料的总多酚含量

研究Folin-Ciocalteu法测定苹果醋饮料中总多酚含量的最适测定条件，并对该方法进行了分析评价。结果表明多酚含量的最佳测定条件为：样品用量1.0mL、福林-酚试剂2.5mL、12%碳酸钠溶液4.0mL、反应温度45℃、反应时间1.5h、测定波长756nm。吸光度与多酚含量在0～6μg/mL范围内呈良好的线性关系(y＝0.1238x＋0.0098，R2=0.9992)，方法的加标回收率为101.2%，相对标准偏差为2.8%(n=5)。该方法精密度高、稳定性好，适用于苹果醋饮料中总多酚含量的测定。

Determination of Total Polyphenols in Apple Vinegar Drink by Folin-Ciocalteu Method

The optimum condition on determining total polyphenols content in apple vinegar drink by Folin-Ciocalteu method was studied. The results indicated that the optimum conditions for total polyphenols determination by Folin-Ciocalteu were as follows: 2.5 mL of Folinphenol reagent was added in 1.0 mL of sample, and then 4.0 mL of 12% sodium carbonate solution was added. After the coloration reaction was for 1.5 h at 45 ℃, the optical density was measured at 756 nm. Under the optimum conditions, the absorbance increased linearly with the concentration of gallic acid in the range of 0 to 6 μg/mL (y=0.1238x+0.0098, R2=0.9992). The average spiked recovery rate was 101.2% with the relative standard deviations of 2.8% (n=5). The method is highly precise and stable, and suitable for determining total polyphenol content in apple vinegar drink.