Determination of aluminum content in fried dough sticks by microwave digestion-chrome azurol S spectrophotometric method

Objective To study a method for determination of aluminum in food, and to ensure food safety and public health. Methods Microwave digestion-chrome azurol S spectrophotometric method was used to detect the aluminum content in fried dough sticks. Detection limit, linear range, precision, accuracy and maximum absorption wavelength were calculated. Results The method detection limit was 0.08 μg, precision was 0.60%-5.90%, and recovery rate was 96.0%-102.3%, maximum absorption wavelengnth was 620 mm. Aluminum content in 10 samples of fried dough sticks were all exceeded the standard, which were 709.5, 980.8, 1 010.3, 1 151.5, 1 214.0, 1 243.7, 1 318.1, 1 374.0, 1 435.0 and 1 479.4 mg/kg. Conclusion The method is simple, reliable, reproducible and easy to be used. Key words: Aluminum; Microwave digestion; Chrome azurol S