RT Journal Article T1 Effect of milk protein composition of a model infant formula on the physicochemical properties of in vivo gastric digestates A1 Niloufar, Rafiee Tari A1 Fan, Ming Z A1 Archbold, Tania A1 Kristo, Eleana A1 Guri, Anilda A1 Arranz Gutiérrez, Elena María A1 Corredig, Milena AB We investigated the effect of protein composition and, in particular, the presence of whey proteins or β-casein on the digestion behavior of a model infant formula using an in vivo piglet model. Three isocaloric diets optimized for piglets were prepared with the same concentrations of protein. For protein source, 1 diet contained only whey proteins and 2 contained a casein:whey protein ratio of 40:60 but differed in the amount of β-casein. To obtain the desired protein compositions, skim milk was microfiltered at 7 or 22°C, and retentates and permeates were combined with whey protein isolate. The diets were optimized to the nutritional needs of the piglets and fed to 24 newborn piglets for 18 d. Eight piglets were also fed ad libitum with sow milk and considered only as reference (not included in the statistical analysis). The study was carried out in 2 blocks, killing the animals 60 and 120 min after the last meal. All gastric contents, regardless of diet, showed a wide range of pH. Postprandial time did not affect the pH or physical properties of the gastric digesta. The digesta from whey protein-casein formulas showed significantly higher viscosity, a higher storage modulus, and a denser microstructure than digesta obtained from piglets fed whey protein formula. The β-casein:total casein ratio at the level used in this study did not significantly affect the physical and chemical properties of the stomach digestate. Although caseins showed extensive gastric hydrolysis, whey proteins remained largely intact at both postprandial times. The results indicate that the presence of different concentrations of milk proteins can be critical to the digestion properties of the food matrix and may affect the nutritional properties of the components. PB Elsevier SN 0022-0302 YR 2018 FD 2018-04 LK https://hdl.handle.net/20.500.14352/93609 UL https://hdl.handle.net/20.500.14352/93609 LA eng NO Tari, N. R., Fan, M. Z., Archbold, T., Kristo, E., Guri, A., Arranz, E., & Corredig, M. (2018). Effect of milk protein composition of a model infant formula on the physicochemical properties of in vivo gastric digestates. Journal of dairy science, 101(4), 2851-2861. NO Natural Sciences and Engineering Council of Canada NO Canadian Dairy Commission DS Docta Complutense RD 4 abr 2025