Mesopic fermentation contributes more to the formation of important flavor compounds and increased growth of Lactobacillus casei Zhang than does high temperature during milk fermentation and storage

Abstract

Probiotic fermented milk is more and more popular due to their positive health associated properties. However, fermentation temperature and other process conditions may affect the growth and metabolism of probiotic strains, thereby affecting quality of the final products. In this study, the growth behaviors and metabolomic profiles of yogurts induced by Lactobacillus casei Zhang at fermentation termination (FT) and d 10 of storage (S10d) under different fermentation temperatures at 37°C (low) and 42°C (high) were analyzed and compared using liquid chromatography-mass spectrometry (MS)-and gas chromatography-MSbased metabolomics approaches. At 37°C, the growth of L. casei Zhang at FT and S10d was significantly increased, and the potential relationship between riboflavin, starch, and sucrose metabolism and growth of L. casei Zhang may be mutually promoting. Fermentation temperature (37°C and 42°C) affected volatile and nonvolatile metabolomic profiles and pathways. The levels of acetaldehyde, 2,3-butanedione, acetoin, butyric acid, decanoic acid, hexanoic acid, and octanoic acid were significantly higher at 37°C than at 42°C at FT and S10d. This indicates that the low temperature (37°C) most likely contributes more to the formation of important flavor compounds during the fermentation process and production of short-chain fatty acids during storage.

Effect of Storage Time and Bacterial Strain on the Quality of Probiotic Goat’s Milk Using Different Types and Doses of Collagens

“…Probiotic bacteria could significantly impact the quality of fermented milk and the formation of metabolites during fermentation and storage [ 2 ]. The viability of lactobacilli in fermented milk depends on several factors, including fermentation time and temperature, product storage conditions, acidity, dry matter and carbohydrate content, bacterial access to nutrients, the presence of oxygen, and the type, species, and strain of lactic acid bacteria used for fermentation [ 67 ].…”

“…Milk-based products account for almost 43% of the functional food market and consist mainly of fermented products [ 1 ]. Probiotic fermented milk is gaining popularity due to its positive health-promoting benefits [ 2 ]. Fermented dairy products often provide carriers of probiotics, and it is well known that these products may enhance human health [ 3 , 4 ].…”

“…Consuming food containing about 10 8 to 10 9 cfu g −1 of probiotic micro-organisms daily provides health benefits to the consumer [ 8 ]. Various bioactive compounds, including peptides, exopolysaccharides, and short-chain fatty acids (SCFAs), could be obtained during the fermentation processes carried out by probiotic bacteria, thus enabling them to exert probiotic effects, such as improving intestinal health, preventing cancer, and improving immune response [ 2 ]. Selecting probiotic strains is based on their safety, functionality, and technological suitability.…”

Exopolysaccharide-Producing Lacticaseibacillus rhamnosus Space Mutant Improves the Techno-Functional Characteristics of Fermented Cow and Goat Milks

“…Then, preprocessing, such as peak extraction, peak comparison, standardization, and normalization, were completed by Progenesis QI software. Collected data were imported into the online tool, MetaboAnalyst 5.0 () for data standardization preprocessing . Then, multivariate statistical analyses were performed.…”

“…Collected data were imported into the online tool, MetaboAnalyst 5.0 (https://www.metaboanalyst.ca/) 31 for data standardization preprocessing. 32 Then, multivariate statistical analyses were performed. The stability of the instrument was evaluated by principal component analysis (PCA) of QC samples and samples to be tested.…”