Browsing by Author "Gomes Reis M"

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    Differences in Aroma Metabolite Profile, Microstructure, and Rheological Properties of Fermented Milk Using Different Cultures
    (MDPI (Basel, Switzerland), 2023-05-02) Nguyen HTH; Gomes Reis M; Wa Y; Alfante R; Chanyi RM; Altermann E; Day L; Božani´c R
    Texture and flavour are the key attributes determining sensory quality and are highly affected by starter cultures. A selection of phenotypic strains is needed to create diverse texture and flavour to meet consumers' preferences. In this study, the use of five lactic acid bacteria strains in the production of fermented milk, along with the metabolite profiles, microstructure, and rheological properties of the fermented milk samples, was investigated. Our results showed that Lactobacillus helveticus (LH) and Streptococcus thermophilus (ST) had a stronger acidification during fermentation but resulted in products with a coarser protein network compared to Lactococcus lactis (BL1) and Leuconostoc mesenteroides (CL3). Milk fermented by LH had the highest viscosity and exopolysaccharide concentration, while milk fermented by ST had the highest concentration of diacetyl. Although Leuconostoc pseudomesenteroides (CL3ST) had a minimal acidification capability, it produced high levels of ethyl-derived compounds associated with sweet, fruity, and floral fragrances. The results demonstrated that LH and ST could be used as starter cultures targeting fermented milks with different viscosities, while BL1, CL3, and CL3ST are suitable as adjunct cultures to impact different acidic sharpness and flavour notes.
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    Lipidomics of Brain Tissues in Rats Fed Human Milk from Chinese Mothers or Commercial Infant Formula
    (MDPI (Basel, Switzerland), 2019-10-28) Su M; Subbaraj AK; Fraser K; Qi X; Jia H; Chen W; Gomes Reis M; Agnew M; Day L; Roy NC; Young W
    Holistic benefits of human milk to infants, particularly brain development and cognitive behavior, have stipulated that infant formula be tailored in composition like human milk. However, the composition of human milk, especially lipids, and their effects on brain development is complex and not fully elucidated. We evaluated brain lipidome profiles in weanling rats fed human milk or infant formula using non-targeted UHPLC-MS techniques. We also compared the lipid composition of human milk and infant formula using conventional GC-FID and HPLC-ELSD techniques. The sphingomyelin class of lipids was significantly higher in brains of rats fed human milk. Lipid species mainly comprising saturated or mono-unsaturated C18 fatty acids contributed significantly higher percentages to their respective classes in human milk compared to infant formula fed samples. In contrast, PUFAs contributed significantly higher percentages in brains of formula fed samples. Differences between human milk and formula lipids included minor fatty acids such as C8:0 and C12:0, which were higher in formula, and C16:1 and C18:1 n11, which were higher in human milk. Formula also contained higher levels of low- to medium-carbon triacylglycerols, whereas human milk had higher levels of high-carbon triacylglycerols. All phospholipid classes, and ceramides, were higher in formula. We show that brain lipid composition differs in weanling rats fed human milk or infant formula, but dietary lipid compositions do not necessarily manifest in the brain lipidome.