UHPLC法快速测定坚果炒货中4种抗氧化剂含量

Rapid determination of four antioxidants in roasted seeds and nuts by UHPLC

为确立快速测定坚果炒货中没食子酸丙酯(Propyl gallate, PG)、叔丁基对羟基茴香醚(Butyl hydroxyanisole, BHA)、二丁基羟基甲苯(2,6-Di-Tert-Butyl-4-Methylphenol, BHT)、特丁基对苯二酚(Tert-Butylhydroquinone, TBHQ)4种抗氧化剂含量的方法,对比坚果炒货样品2种前处理方法,选择色谱柱及流动相建立测定坚果炒货中4种抗氧化剂含量的超高效液相色谱法(UHPLC),粉碎后的样品直接经甲醇充分提取,提取液无须净化和浓缩,过滤膜后上机检测,滤液中4种抗氧化剂通过CORTECS C18色谱柱在8 min内得到快速分离并经PDA检测器实现准确定量。对UHPLC法进行方法学验证,结果表明:4种抗氧化剂在10~200 mg/L范围内线性关系良好,相关系数均大于0.998,PG、BHA、BHT、TBHQ的检出限依次是1.0、2.0、2.0、2.0 mg/kg,定量限依次是3.0、6.0、6.0、6.0 mg/kg,平均回收率在95.06%~104.31%之间,RSD为0.1%~2.1%。与国标法相比,UHPLC法具有简单快捷、成本低、回收率高、灵敏度高等优势,可用于坚果炒货中4种抗氧化剂含量的大批量检测。

Common food antioxidants, such as BHA, BHT, TBHQ and PG, have been widely used in various food production and processing. The limits of antioxidants utilized are clearly defined in our countries. GB 2760-2014 “Use standard of food additives” stipulates that BHA, BHT and TBHQ should not exceed 200 mg/kg and PG should not exceed 100 mg/kg in roasted seeds and nuts. A rapid method for the determination of four antioxidants in roasted seeds and nuts had been established by ultra high-performance liquid chromatography(UHPLC). Two pre-treatment methods was established and their effects on determination of four antioxidants in roasted seeds and nuts were compared. After being crushed, the samples were directly extracted with methanol without being purified by purifying column and concentrated, then, the four antioxidants in the filtrate were separated by CORTECS C18 column within 8 minutes and accurately quantified by PDA detector. The linearity of the four antioxidants was good in the range of 10-200 mg/L, and the correlation coefficients(R) were all greater than 0.998. The detection limits of PG, BHA, BHT and TBHQ were 1.0 mg/kg, 2.0 mg/kg, 2.0 mg/kg and 2.0 mg/kg, respectively. The limits of quantitation were 3.0 mg/kg, 6.0 mg/kg, 6.0 mg/kg and 6.0 mg/kg, respectively. The average recoveries ranged from 95.066% to 104.31%, and RSD ranged from 0.1% to 2.1%. Compared with the national standard method, this method in the present work showed advantages of simple and fast, low cost, good recovery and high sensitivity, which can be used for the mass determination of four antioxidants in roasted seeds and nuts.