L-Cysteine involved Maillard peptides of distillers' grain hydrolysates: Browning, formation of characteristic flavor and improvement on fracturability of sugared garlic

Maillard peptides (MPs) were derived from distillers' grain hydrolysates (DGPs) and fructose, and MPs prepared with and without exogenous L-cysteine were respectively defined as DFCs and DFs. The influences of extra-added L-cysteine was investigated on the browning, taste properties (salty, umami, and kokumi), and characteristic volatile compounds of MPs. Eleven aroma-active compounds were identified as the key volatile compounds of MPs through aroma extract dilution analysis (AEDA) and odor active values (OAVs). Partial least squares regression (PLSR) was used to investigate the relationship between the sensory properties and the concentrations of the volatile compounds in DFCs and DFs. 3-Methylbutanal, 5-methyl-2-thiophenecarboxaldehyde, dimethyl trisulfide, trimethylpyrazine, and 3-ethyl-2,5-dimethylpyrazine, which significantly contributed to the caramel and roast characteristics of MPs, were inhibited through the addition of L-cysteine and regulation of temperature below 120 degrees C. The DFCs prepared at 110 degrees C for 120 min exhibited desirable taste properties and suitable aroma to non-thermal processed foods. When 0.3% DFCs were added to the soaking solution of sugared garlic, the hardness and fracturability of sugared garlic were increased by 45.26% and 19.15%, respectively, which meant this MPs could be used to improve the edible texture of sugared garlics.