ABSTRACT
Objective: To establish a method for the determination of D-fructose, D-glucose, sucrose, D-maltose, and other four main carbohydrates in Hordei Germinatus Fructus (HGF) by HPLC-ELSD, as well as explore the dynamic changes of reducing sugar and non-reducing sugars in stir-frying process of HGF and provide scientific basis for clarifying the mechanism of digestion effect of HGF. Methods: HGF samples were prepared with different stir-frying temperature and time. The contents of fructose, glucose, sucrose, maltose, and other four main carbohydrates were determined by HPLC-ELSD method. HCA and PLS-DA were used to analyze the changes of four main carbohydrates in the stir-frying process. Results: The contents of fructose, glucose, maltose, and other three kinds of reducing sugar showed a downward trend on the whole with temperature increasing. And non-reducing sugar such as sucrose increased firstly and then decreased. HGF under different temperature was divided into three categories by HCA. PLS-DA showed that the stir-frying temperature had main effect on the content of sucrose, and the effect of reducing sugar such as fructose, glucose, and maltose was relatively small. With the extension of stir-frying time, the contents of four carbohydrates decreased and reached steady-state at 16 min. HGF with different stir-frying time was divided into four categories by HCA. Standardized A420 value increased with the frying time increasing, and reached the peak at 16 min. Conclusion: The contents of reducing sugar, non-reducing sugar, and amino acids decreased in HGF, which is caused by Maillard reaction directly or indirectly in stir-frying process. The products of Maillard reaction may be associated with digestion effect of HGF.