Abstract: The dissolution and speciation distribution of Pb, Cd, Zn, Ni, and Co from ceramic packaging of Baijiu were investigated by the BCR extraction method, microwave digestion and acetic acid extraction. Results showed that the total sum of heavy metals in the ceramic packaging detected by the BCR method was 84.90%–109.38% as compared to microwave digestion, and heavy metal concentrations consistently decreased in the order of Zn > Ni > Pb > Co > Cd. Based on the BCR speciation distribution of heavy metals from the ceramic packaging, the dissolution risk of Ni and Zn was the most serious among all heavy metals, Pb and Co had medium risk of dissolution, and there was almost no risk of Cd dissolution. In addition, the total concentration of weakly acid extractable and reducing species with BCR extraction was 79.55%–411.75% as compared to 4% acetic acid extraction for 24 h. The results of correlation analysis showed that there was a more significant correlation between the weakly acid extractable species and heavy metal dissolution in 4% acetic acid. Correlation analysis of the BCR extractable species indicated that ceramic packaging may have increased risk of dissolution of heavy metals when it is used to store Baijiu containing acid and reducing and oxidizing substances for a long time. Therefore, the BCR extraction method is useful to further analyze the speciation characteristics of dissolved heavy metals from Baijiu ceramic packaging, which can provide a scientific basis for exploring the influence of heavy metal dissolution on Baijiu quality and human health risk.

Key words: BCR extraction, Baijiu, ceramic packaging, heavy metals, dissolution