Preliminary Observations on the Interactions Between Chlorogenic Acid and Select Amino Acids

This report presents our preliminary observations regarding the interactions between chlorogenic acid and select amino acids or tyramine. In most cases, these interactions resulted in the formation of a green pigment in line with published reports. However, in the case of tryptophan a green or red pigment was generated depending on the concentration of tryptophan that was present. In the cases of serine or threonine the green pigment that was generated in the first minutes of the reactions disappeared entirely when the mixtures were kept reacting for longer periods of time. Published reports indicate that the formation of the green pigment between chlorogenic acid and amino acids involves a covalent interaction between both. In our experiments we did observe the disappearance of chlorogenic acid during the reactions but in the cases of tryptophan or tyrosine no decline in the concentration of both amino acids could be observed. This was in contrast to the reaction between chlorogenic acid and tyramine where the concentration of both compounds declined while producing a green pigment.