Abstract:Salted duck is a local specialty dish of Nanjing and has been designated as a Geographical Indication (GI) product of China. It is popular among consumers owing to its unique flavor and production process. However, comprehensive quality analyses of Nanjing salted duck are limited. Therefore, the present study aimed to compare the quality of different brands of Nanjing salted duck. In particular, six brands of commercially available Nanjing salted duck products were selected for comprehensive analysis of quality attributes (protein, fat, inosinic acid, and free amino acid contents and fatty acid composition and content) using multivariate statistical methods. There were significant differences (P<0.05) in quality among the six brands of Nanjing salted duck. The protein content was 20.9%~31.46%, while the inosinic acid and total free amino acid contents were 36.45~128.05 mg/100 g and 20.47~36.78 g•kg-1, respectively. Glutamic acid and valine were the main taste-active amino acids in Nanjing salted duck. The saturated fatty acid and polyunsaturated fatty acid contents were 9.82%~14.67% and 52.69%~60.69%, respectively, with the former being significantly higher in brand H1 and the latter being significantly higher in brand H2 than in other brands. A total of 11 differential substances (protein, IMP, C16:0, C18:0, C16:1, C18:1n-9c, C18:2n6c, C18:2n6t, C18:3n3, C18:3n6, and C22:6n3) were screened by OPLS-DA, with brand H1 having the highest IMP and C22:6n3 contents. These findings explain the savory flavor and diverse quality attributes of Nanjing salted duck from the perspective of nutrient compositions and can serve as reference for purchasing decisions of consumers.
