Abstract: 【Objective】Discoloration during storage is a key problem that limits the shelf-life of cooked cured meats. The purpose of the experiment is to study the relationship of color parameters and amino acids and biogenic amines of sliced cooked cured beef ham (SCCBH), to reveal the effects of the nitrogen compounds in meat products on the stability of the heme pigment and apparent color, in the hope of providing theoretical guidances for color protection of this type of products. 【Method】Color parameters, free amino acids and biological amines of SCCH during storage were examined and factor analysis was used to explain the effect of free amino acids and biogenic amines on the color parameters. Principal component analysis (PCA) was used to extract the principal factor. Varimax orthogonal rotation with Kaiser normalization method was adopted in data analysis. 【Result】Eight kinds of biogenic amines and 16 kinds of free amino acids were detected in this experiment. Biological amines showed no significant changes during storage, while, threonine (Thr), valine (Val), methionine (Met), lysine (Lys) and arginine (Arg) changed significantly. The factor analysis results showed that the ?rst principal factor (F1) explained 45.72% of the total variation, and the second (F2) explained 21.52%. F1 was a concentrated reflection of color changes of SCCBH during storage, especially of the redness (a*), Chroma (C) and pigment NO-Heme (NH), and nitrogen compounds directly affecting the apparent color. F2 was mainly expressed the information of the hue and of the nitrogen compounds indirectly affecting apparent redness through the hue (H) or yellowness (b*), these nitrogen compounds mainly contained acidic and alkaline free amino acids. Tyramine (TYR) and spermine (SPM) significantly affected the stability of heme pigment and apparent color of SCCBH, which were shown by a high factor loading value (0.98) in F1. Further, TYR and SPM negatively correlated with the color parameters of SCCBH. Tryptamine (TRY) could keep the NH stable and improve the redness of SCCBH due to the higher factor loading (0.78) in F1 and a significant positive correlation with redness and NH. Threonine and histidine (His) were significantly positively related with redness of SCCBH. Valine, tyrosine (Tyr), methionine and leucine (Leu) had a significant negative correlation with the redness. In addition, glycine (Gly) also had a negative correlation with the redness, but its effect on the apparent color was relatively weak due to its low factor loading in F1. Proline (Pro) had a higher loading (0.78) in F1 and notably related with all of the color parameters, so it affected the color stability apparently. The effect of Pro on the lightness (L*) and yellowness was greater than on the redness just because the correlation coefficients with lightness and yellowness were much higher than it was with redness. Phenylalanine (Phe), lysine and arginine indirectly affected the redness through the lightness and yellowness on the basis of the facts that the three amino acids having high factor loadings in F2 (the factor loadings of Phe, Lys and Arg in F2 were 0.90, 0.94, and 0.97, respectively) significantly related with lightness and hue. The factor loading of glutamate (Glu) in F1 was relatively higher (0.61), which was significantly related to the yellowness and lightness but no effect on redness.【Conclusion】The content and form of the free amino acids and biogenic amines in the meat matrix significantly affected the color stability. This effect might be influenced by matrix pH changing, the combination and competition with porphyrin iron.

Key words: sliced cooked cured beef ham , color , free amino acids , biogenic amines , factor analysis