Study on the Formation of Alkyl Pyrazine in 1, 3-Dihydroxyacetone Carbonyl Ammonia Reaction System

Alkylpyrazine is an important flavor component of food, and it is also one of the products of carbonyl ammonium reaction. In order to explore the new alkylpyrazine reaction model in the carbonyl ammonium reaction system and the law of alkylpyrazine formation in the model, in this paper, ammonium salts and dihydroxyacetone were used as substrates. The effects of the type, time, temperature, concentration, ratio and pH of ammonium salts on the production of different alkylpyrazine (APZ) from dihydroxyacetone were studied. Taking APZ production amount as the standard, the APZ content was the highest (4.59±0.11) mg/L when ammonium chloride reacted with dihydroxyacetone among the five ammonium salts. Optimum extraction conditions were concluded as follows:Time of 15 h, concentration of 3.7 mol/L, reaction ratio of 1:1, pH of 3.With ammonium chloride and dihydroxyacetone as the reaction substrate, the content of APZ increased with the increase of temperature. With the increase of the reaction time, the content of APZ increased first and then decreased, the formation of 2, 3, 5-trimethyl pyrazine and tetramethylpyrazine follows a zero-order reaction law. With the increase of the reaction concentration, the content of APZ production first increased and then decreased, and the concentration of dihydroxyacetone was fixed, and as the proportion of ammonium chloride concentration increased, the APZ content also showed a trend of rising first and then falling. In a weakly acidic environment, it was more conducive to the formation of APZ.