Figure 9. Correlation matrix demonstrating the degree of linear relationship between amino acids. Figure 9. Correlation matrix demonstrating the degree of linear relationship between amino acids. The variables are ordered according to the value of the Pearson correlation coe ffi cient. The lighter the The variables are ordered according to the value of the Pearson correlation coefficient. The lighter the color, the lesser the coe ffi cient value between two variables. Only significant correlations are depicted; color, the lesser the coefficient value between two variables. Only significant correlations are depicted; insignificant correlations are leaved blank. No negative correlation between amino acids was insignificant correlations are leaved blank. No negative correlation between amino acids was observed.