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Lotus (Nelumbo nucifera Gaertn.) seeds are rich in proteins and are considered to be a beneficial source of plant proteins. In this study, lotus seed protein hydrolysate (LSPH) was prepared using Flavourzyme and antioxidant activities were evaluated. The LSPH possessed the highest DPPH-scavenging (EC 50 2.9 mg/mL), H 2 O 2 -scavenging (EC 50 16.1 mg/mL), and reducing power activity (8.0 mg/mL) at 180 min of hydrolysis. After gel filtration and reverse phase HPLC purification, the low molecular weight fraction was then analyzed by Nano-LC-MS/MS. Sixteen peptides with corresponding mass from 1 to 2 kDa were identified. Peptides with hydrophobic features and acidic amino acids, Asp and Glu, are considered to contribute to overall antioxidant activities. These results show Flavourzyme hydrolysis of lotus seed protein successfully generates low molecular fragments that make them a potential nutraceutical or health promoting supplement. [Display omitted] • Flavourzyme effectively hydrolyze lotus seed protein to reach 79.5% DH. • The degree of hydrolysis was negatively correlated with antioxidant activities. • The fraction with the smallest molecular weight has the best antioxidant activities. • Nano-LC-MS/MS was applied to characterize antioxidative peptide sequences. • Sixteen peptides with 8–17 residues were identified from an antioxidative fraction. [ABSTRACT FROM AUTHOR]

To develop objective methods of oolong tea grading for importers and customs, metabolomics and sensory evaluation were applied to screen the characteristic compounds associated with Tieguanyin (TGY) tea grades T, 1, 2, and 3, and types (fresh scent flavor and high fragrance). With decreasing TGY grade/quality, the astringency and content of most flavonoid glycosides increased (especially catechin and epicatechin). The floral aroma of fresh scent flavor TGY decreased, and the roasted aroma of high-fragrance TGY increased with decreasing TGY grade. Five non-volatile compounds (epicatechin gallate, quercetin-3- O -galactoside, quercetin-3- O -rutinoside, epicatechin, and gallocatechin) and five volatile compounds (benzyl benzoate, β -phenylethyl acetate, 6-methyl-5-hepten-2-one, heptanal, and (E)-2-hexenal) were identified, which could readily distinguish different grades of fresh scent flavor and high fragrance TGY by quantitative chemical analysis. Lower grades of TGY had inferior flavor, but higher antioxidant capacity. • Sensory evaluation and metabolomics were combined for Tieguanyin grade analysis. • As Tieguanyin grades decreased, the astringency increased. • Ten compounds were identified as the key metabolites for Tieguanyin grades. • Low-grade tea has higher antioxidant capacity due to more polyphenols. [ABSTRACT FROM AUTHOR]

Daqu is an essential component in the solid-state fermentation of Chinese Baijiu, and non- Saccharomyces yeasts from Daqu significantly contribute to the complex flavors in Baijiu. However, the potential of non- Saccharomyces yeasts from Daqu in beer production has remained unexplored. In this study, 80 strains representing 14 non- Saccharomyces yeast species were isolated from various Daqu. These strains were scrutinized for their stress tolerance, flocculation, fermentation performance, and the production of flavor compounds. Subsequently, representative strains were chosen for beer production, and the resulting products from both single- and mixed-strain fermentations underwent sensory evaluation. Toruaspora delbrueckii TD2 exhibited excellent fermentation properties in wort. In compared to US-05, the non- Saccharomyces yeast strains tested significantly increased volatile favor compounds. Notably, the Wickerhamomyces anomalus strain showed a 13.86-fold increase in ethyl acetate production, while the Hanseniaspora osmophila strain displayed a 7-fold increase in phenylethyl acetate production. Co-fermentations of these strains with US-05 did not impact attenuation and ethanol concentration but significantly enhanced aromatic profiles. This study offers valuable insights into the fundamental attributes and brewing potential of non- Saccharomyces yeasts sourced from Daqu , broadening the spectrum of yeast selection for the creation of innovative beers. • Non- Saccharomyces yeasts from Daqu were isolated and evaluated for beer brewing. • Wickerhamomyces anomalus produces 13.86 times more ethyl acetate than US-05. • Hanseniaspora osmophila fermentation was 7-folds increase in phenylethyl acetate. • Non- Saccharomyces significantly enhance aromatic esters in mixed-fermentation with S. cerevisiae. • Mixed-fermentation could produce fruity-like beer between H. osmophila and T. delbrueckii. [ABSTRACT FROM AUTHOR]

The quality and safety of Pu-erh tea are largely determined by microorganisms, processing and storage conditions. The systemic co-relationship between microbiome and metabolomics during manufacturing of Pu-erh tea is not fully clarified. We comprehensively explored the microbial and metabolic dynamic evolution and revealed the decisive factors for the quality and safety of Pu-erh tea based on creative methods. The results showed that fungal abundance increased in the middle of pile fermentation period and then decreased during storage, but the bacterial abundance increased in the initial stage, subsequently decreased and finally increased. All microorganism species as well as dominant fungi and bacteria were identified during different processing steps. A total of 209 metabolites were identified and 50 of them were characterized as critical metabolites responsible for metabolic changes. Multivariate analysis verified that these critical metabolites were generated by specific dominant species. The environmental condition exhibited a great effect on the growth and reproduction of bacteria, but less than 10% of the dominant fungi exhibited significant correlation with temperature and humidity. In conclusion, our results revealed the microbial composition is the critical factor in changing the metabolic profile and provided a theoretical basis for improving the quality and safety of Pu-erh tea. • We explored the correlation between microbiome and metabolomics of Pu-erh tea. • Creative methods were used to clarify microbial and metabolic dynamic evolution. • The environmental condition affected the growth and reproduction of microorganism. • This study revealed the decisive factors for the quality and safety of Pu-erh tea. [ABSTRACT FROM AUTHOR]