Abstract: A flame atomic absorption spectrophotometric (FAAS) method to determine calcium in Chinese distillate spirits was presented without the need for sample pretreatment. The effects of reaction system composition, releasing agent concentration, acetylene flow rate and burner height on the absorbance at 422.7 nm of the reaction system were explored. Quantification methods such as standard curve method and standard addition method were compared for their effects on calcium quantification. Our results illustrated that the error caused by incompatibility could be eliminated by using 50% aqueous ethanol as standard sample. Therefore, the standard curve method was selected for calcium quantification. Under the optimal conditions, the linear range of quantification of the method was 0.2－8μg/mL, with a detection limit of 0.17μg/mL. The calcium content of a certain commercial sample was determined by the method to be 9.73μg/mL, and the precision RSD for 6 parallel determinations was 2.04%. The average spike recovery across three levels was 101.5% with a relative standard deviation of 2.73%. The method was direct, rapid, accurate and stable and had great value for practical applications.

Key words: direct sampling, flame atomic absorption spectrophotometry, Chinese distillate spirits, calcium