In this study, Agaricus bisporus and pork bone stocks (PBS) were enzymatically digested, and the equivalent umami concentration (EUC) value, sensory evaluation and hydrolysis degree (DH) were used as indexes to find the optimal enzyme digestion conditions. Finally, the optimal enzymatic solution was mixed and analyzed for flavor compounds in the optimal enzymatic solution before and after Maillard reaction (MR) by GC × GC-O-MS. The results showed that the enzymatic digestion of mushroom stocks (MS) with a combination of Cellulase-Protamex™ (C-P) yielded high levels of flavor amino acids (40.733 ± 0.340 g/L), and 5′-nucleotides (12.807 ± 0.239 mg/g), and EUC values up to 1755.786 ± 40.759 g/100 g. Meanwhile, the simultaneous enzymatic hydrolysis of PBS with a combination of Flavourzyme™-Protamex™ (F-P) yielded high levels of flavor amino acids (51.265 ± 0.550 g/L) and 5′-nucleotides (17.477 ± 0.260 mg/g) with EUC values up to 3420.619 ± 114.193 g/100 g. Using the DH and sensory evaluation as indicators, the results showed that the greatest DH and the highest sensory scores were obtained with the addition of C-P-MS and F-P-MS at 7:3 (m/m). Finally, the compounds with large changes in concentration were mainly mushroom flavored 1-octen-3-ol (2208.614 ± 12.879 μg/kg), sweet-flavored 3-octanone (269.871 ± 11.691 μg/kg), floral-flavored benzyl alcohol (156.704 ± 14.859 μg/kg), green flavored 2-pentylfuran (190.470 ± 12.934 μg/kg), and almond-flavored furfural (523.555 ± 5.674 μg/kg).
Zongbao Sun,Haodong Pan,Min Zuo,Junkui Li,Liming Liang,Chi-Tang Ho,Xiaobo Zou
This study utilized equivalent umami concentrations (EUC) to characterize umami intensity in salmon with different freeze–thaw times. A rapid and non-destructive method was established to determine EUC values in salmon which is based on hyperspectral imaging (HSI) system combined with multiple characteristic variable screening methods. The established CARS-PLS model showed greater advantages in correlating the reference values of spectral data with EUC in salmon with Rc of 0.9012, Rp of 0.9009, RMSECV of 0.82, and RMSEP of 0.88. The model was employed pixel-wise to visualize the distribution of EUC with different freeze–thaw times, which demonstrated the reduction of EUC value with the increasing of freeze–thaw times. Therefore, this reseearch showed hyperspectral imaging (HSI) system combined with chemometrics possesses a substantial capability to predict and visualize the EUC of salmon, which would provide an intuitive understanding of salmon quality prediction and detection.
Button mushroom slices were dehydrated using freeze drying (FD) or FD combined with microwave vacuum drying (FMVD), and the non-volatile component profiles were studied. The results showed that the level of non-volatile components in button mushroom firstly increased during sublimation of FD/FMVD process and then fell during desorption in FD process and MVD in FMVD process. Compared to FD products, the contents of soluble sugars and polyols in FMVD products were relatively low, whereas the contents of total free amino acids were significantly higher, close to the level of fresh mushroom. However, there was no significant difference in the contents of 5′-nucleotides and organic acids between FD and FMVD products. The equivalent umami concentration ( EUC ) values for FD and FMVD products did not differ from fresh, indicating that both drying methods could effectively preserve MSG (monosodium glutamate)-like components in button mushroom.
危险品化学品经营许可证（带存储）