Exploring the Mechanism of Liquid Smoke and Human Taste Perception Based on the Synergy of the Electronic Tongue, Molecular Docking, and Multiple Linear Regression

Study on the effect of enzymolysis combined fermentation on reducing the off-flavor of egg white powder

BACKGROUND

The application of egg white powder (EWP) was subject to its off-flavor. In the present study, flavourzyme and lactic acid bacteria were used to treat egg white powder (EWP) and the mechanism effects of enzymolysis-fermentation were explored.

RESULTS

Compared with the control group, enzymolysis combined with fermentation treatment group (EW-EF) reduced the four-representative off-flavor compounds (geranyl acetone, 1-octen-3-ol, octanal and nonanal) by more than 62.66%. Fermentation produced esters with good flavor, and enzymolysis produced fresh amino acids. Characterization of protein structure indicated that fermentation decreased both fluorescence intensity and surface negative charges, accelerating the aggregation of proteins; enzymolysis promoted aggregation and degradation, improving the stability of the egg white proteins. Meanwhile, enzymolysis broke down the hydrophobic cavities bound to off-flavor compounds, releasing protein-bound off-flavor compounds and removing them through fermentation.

CONCLUSION

EW-EF had the best effect of off-flavor removal on EWP. The results of the present study could provide a green and effective method for improving the flavor of EWP. © 2024 Society of Chemical Industry.

Hydrogen bonds and hydrophobicity with mucin and α-amylase induced honey aroma in Feng-flavor Baijiu during 16 years aging

Honey aroma is one of the most significant factors of Feng-flavor Baijiu, which is also an essential element to attract consumers. However, the evaluation and chemical basis of honey aroma is unclear. Palmitoleic acid, lagochilin, phomotenone and ethyl behenate were confirmed to be the strongest contributors to honey aroma by time-intensity analysis and UHPLC-Q-Orbitrap-MS. Predictive modeling was developed for processing honey aroma intensity responses in order to obtain significant Feng-flavor Baijiu rankings. In this study, the effects of ex-vivo saliva on Feng-flavor Baijiu were investigated for the first time. Mucin and α-amylase, as major proteins in ex-vivo saliva, were applied to simulate molecular docking of ethyl benzoate. Mucin and α-amylase modified the aroma release, which depended on hydrogen bonds and hydrophobic interactions, respectively. It is blazing a trail in the field in sensory experience of Feng-flavor Baijiu as well as contributes to our understanding of Feng-flavor Baijiu drinking process.

Characterization of the Volatile Compounds of Zhenba Bacon at Different Process Stages Using GC-MS and GC-IMS

Zhenba bacon (ZB), a type of Chinese traditional bacon with a long history, has attracted considerable attention in the Southwest of China for its unique flavor. To elucidate the changing course of aroma components during the process of ZB, four stages of process stages were assessed by GC-MS and GC-IMS coupled with multivariate data analysis. A total of 44 volatile compounds were identified by GC-IMS, including 5 esters, 8 alcohols, 12 aldehydes, 3 ketones, 1 furan and 2 sulfides; 40 volatile compounds were identified by GC-MS, 4 ketones, 7 phenols, 8 alcohols, 6 esters, 6 aldehydes, and 6 other compounds were detected. During the curing period, the amount and content of esters in Zhenba bacon gradually increased. Phenols appear in large quantities during the smoking period. The VOCs (volatile organic compounds) in the gallery plots were the most diverse in YZ samples, which are mainly esters. POV (peroxide value) and TBARS (thiobarbituric acid reactive substance) showed that lipid oxidation played an important role in the formation of volatile flavor components of bacon. This study provides valuable analytical data to explain the flavor formation of Zhenba bacon.

Identification of nut protein-derived peptides against SARS-CoV-2 spike protein and main protease

Recently, an outbreak of a novel coronavirus disease (COVID-19) has reached pandemic proportions, and there is an urgent need to develop nutritional supplements to assist with prevention, treatment, and recovery. In this study, SARS-CoV-2 inhibitory peptides were screened from nut proteins in silico, and binding affinities of the peptides to the SARS-CoV-2 main protease (M^pro) and the spike protein receptor-binding domain (RBD) were evaluated. Peptide NDQF from peanuts and peptide ASGCGDC from almonds were found to have a strong binding affinity for both targets of the coronavirus. The binding sites of the NDQF and ASGCGDC peptides are highly consistent with the M^pro inhibitor N3. In addition, NDQF and ASGCGDC exhibited an effective binding affinity for amino acid residues Tyr453 and Gln493 of the spike RBD. Molecular dynamics simulation further confirmed that the NDQF and ASGCGDC peptides could bind stably to the SARS-COV-2 M^pro and spike RBD. In summary, nut protein may be helpful as nutritional supplements for COVID-19 patients, and the screened peptides could be considered a potential lead compound for designing entry inhibitors against SARS-CoV-2.