Browsing by Author "Zhu P"

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    Interfacial composition of coenzyme Q10 emulsions impacts coagulation of fortified milk during gastric digestion
    (Elsevier Ltd, 2025-02-01) Wang X; Zhu P; Ye A; Singh H; Acevedo-Fani A
    This study aimed to investigate the gastric digestion behaviour of heat-treated enriched milk containing Coenzyme Q10-loaded emulsions with different interfacial compositions. Four enriched milk types were compared: pasteurized with a Tween 80 stabilised emulsion (PAST-TW80), or with a sodium caseinate-stabilised emulsion (PAST-NaCN), and UHT with a TW80-stabilised emulsion (UHT-TW80), or PAST with a NaCN-stabilised emulsion (UHT-NaCN); all loaded with Coenzyme Q10. An in vitro dynamic gastric digestion model (Human Gastric Simulator) was utilized and the kinetics of milk coagulation and emptying of protein, lipid and Coenzyme Q10 were monitored. Adding NaCN-stabilised emulsion to heated milk led to a largely fragmented curd with signs of extensive droplets coalescence, disintegrating rapidly and accelerating protein and lipid release. Heated milk with TW80-stabilised emulsion produced a compact and closely integrated curd with limited coalescence, slowing nutrient emptying. UHT milk showed more curd fragmentation than PAST milk, regardless of emulsion type. The release profiles of Coenzyme Q10 were similar between UHT-TW80 and PAST-TW80 or between PAST-NaCN and UHT-NaCN, indicating the emulsion's interfacial composition as a key factor in controlling lipophilic bioactive release from the food matrix, regardless of heat treatment. These findings demonstrate that the emulsion's interfacial composition (NaCN vs TW80) and the heat treatment (PAST vs UHT) can be combined as a strategy to modulate milk coagulation kinetics and the rate of nutrient delivery to the small intestinal stage. This study provides insights into the development of functional milk products fortified with lipophilic bioactive compounds, as well as strategies for optimizing the controlled release of these compounds upon consumption.
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    Investigation of the gastric digestion behavior of commercial infant formulae using an in vitro dynamic infant digestion model.
    (Frontiers Media S.A., 2024-12-05) Descallar FB; Roy D; Wang X; Zhu P; Ye A; Liang Y; Pundir S; Singh H; Acevedo-Fani A; Lambers T
    The gastric digestion behavior of different commercial Stage 1 infant formulae (for 0-6 months) with different formulation backgrounds was investigated using an in vitro dynamic infant human gastric simulator (iHGS). The microstructural arrangements of the protein and lipid, colloidal stability and protein hydrolysis during digestion were elucidated. During gastric digestion, casein-dominant formulations showed a higher extent of aggregation due to their high proportion of casein micelles that underwent coagulation upon acidification and via the action of pepsin. The extensive protein coagulation/curd formation in casein-dominant infant formulae slowed the rate of protein hydrolysis and resulted in the retention of caseins in the iHGS for longer times. Confocal micrographs showed that oil droplets were entrapped in the curd particles of casein-dominant infant formulae, which consequently slowed the gastric emptying of lipids. Conversely, whey-dominant formulations showed a lower degree of protein aggregation that resulted in faster protein hydrolysis and rapid protein and lipid emptying from the iHGS. It was also revealed that whey-dominant infant formulae in the presence of biopolymers increased the viscosity of gastric chyme and induced the flocculation of oil droplets. This altered the rate of protein hydrolysis and emptying of lipids. Correlation analyses depicted the overall kinetics of gastric emptying of macronutrients during digestion and comprised two stages: (i) driven by the continuous stomach emptying and (ii) influenced by aggregation and coalescence indices. The present study highlights the similarities and differences in the digestion behaviors of commercial infant formulae based on important ingredients such as types of proteins and biopolymers, regardless of the formulation or processing histories.