Investigation of Maillard reaction involvement in the steam processing of &lt;i&gt;Panax Notoginseng&lt;/i&gt; root

Jiang-Hua Li,Yu-Jie Liu,Zhi-Jie Yu,Rui-Zhen Huang,Mei-Bian Hu,Chun-Jie Wu,Yong-Liang Huang

doi:10.4314/tjpr.v17i2.15

Abstract

Purpose: To explore the possible mechanism of Maillard reaction (MR) involvement in the steam processing of Panax notoginseng (PN) root.Methods: PN root was soaked in water for 24 h and then steamed at 100 °C using an autoclave for 1, 2, 3, 4, 5 and 6 h, respectively. Several indicators associated with MR during steam processing were measured. The pH and absorbance at 420 nm (A420) of samples were measured using a pH meter and an ultraviolet-visible spectrophotometer, respectively. The contents of 5-hydroxy-methyl-furfural (5-HMF) and sugars were determined by high performance liquid chromatography (HPLC) while amino acids were evaluated using an automatic amino acid analyzer.Results: During PN root steam processing (0 - 6 h), pH value gradually decreased from 6.35 ± 0.02 to 5.88 ± 0.03 while A420 value gradually increased from 0.23 ± 0.01 to 0.44 ± 0.02. The levels of reducing sugars (maltose and glucose) and amino acids (aspartic acid, glutamate, cysteine, lysine and arginine) in PN root decreased after steaming for 6 h. However, the content of 5-HMF in PN root increased with increase in steaming time.Conclusion: The results indicate that MR occurs during steam processing of PN root, and the reaction mechanism might be closely related to the reaction between the reducing sugars and amino acids.Keywords: Panax notoginseng, Steaming, Reducing sugars, Amino acids, Maillard reaction

Highlights

Maillard reaction (MR), known as non-enzymatic browning reaction, is the principal chemical reaction in food processing
MR, known as non-enzymatic browning reaction, is the principal chemical reaction in food processing. It is a reaction between carbonyl compounds and amino compounds [1,2], and it often occurs during the steam processing of many traditional Chinese medicines [3]
The results showed that the content of 5-HMF increased with the steaming time during the steam processing

Summary

INTRODUCTION

MR, known as non-enzymatic browning reaction, is the principal chemical reaction in food processing It is a reaction between carbonyl compounds (reducing sugars, ketones or aldehydes) and amino compounds (amino acids, proteins or any nitrogenous compound) [1,2], and it often occurs during the steam processing of many traditional Chinese medicines [3]. Sample preparation: A 10 mL volume of 40 % (v/v) methanol was added to 0.5 g of the PN root powder and extracted by an AS5150A ultrasonic extractor (Auto science, Tianjin, China) for 30 min at room temperature, the solutions were filtered through a 0.22 μm nylon filter membrane before analysis. The mixture of standard solutions were prepared by dissolving fructose (5.65 mg), glucose (7.49 mg), sucrose (5.76 mg) and maltose (5.63 mg) with 5 mL deionized water.

RESULTS

DISCUSSION

CONCLUSION

Conflict of interest