Influence of calcium-binding salts on heat stability and fouling of whey protein isolate dispersions

peer-reviewedThe effect of the calcium-binding salts (CBS), trisodium citrate (TSC), tripotassium citrate (TPC) and disodium hydrogen phosphate (DSHP) at concentrations of 1–45 mm on the heat stability and fouling of whey protein isolate (WPI) dispersions (3%, w/v, protein) was investigated. The WPI dispersions were assessed for heat stability in an oil bath at 95 °C for 30 min, viscosity changes during simulated high-temperature short-time (HTST) and fouling behaviour using a lab-scale fouling rig. Adding CBS at levels of 5–30 mm for TSC and TPC and 25–35 mm for DSHP improved thermal stability of WPI dispersions by decreasing the ionic calcium (Ca2+) concentration; however, lower or higher concentrations destabilised the systems on heating. Adding CBS improved heat transfer during thermal processing, and resulted in lower viscosity and fouling. This study demonstrates that adding CBS is an effective means of increasing WPI protein stability during HTST thermal processing

Influence of calcium-binding salts on heat stability and fouling of whey protein isolate dispersions

The effect of the calcium-binding salts (CBS), trisodium citrate (TSC), tripotassium citrate (TPC) and disodium hydrogen phosphate (DSHP) at concentrations of 1–45 mm on the heat stability and fouling of whey protein isolate (WPI) dispersions (3%, w/v, protein) was investigated. The WPI dispersions were assessed for heat stability in an oil bath at 95 °C for 30 min, viscosity changes during simulated high-temperature short-time (HTST) and fouling behaviour using a lab-scale fouling rig. Adding CBS at levels of 5–30 mm for TSC and TPC and 25–35 mm for DSHP improved thermal stability of WPI dispersions by decreasing the ionic calcium (Ca2+) concentration; however, lower or higher concentrations destabilised the systems on heating. Adding CBS improved heat transfer during thermal processing, and resulted in lower viscosity and fouling. This study demonstrates that adding CBS is an effective means of increasing WPI protein stability during HTST thermal processing

The impact of the Maillard reaction on the in vitro proteolytic breakdown of bovine lactoferrin in adults and infants

The Maillard reaction has been proposed as a natural pathway to functionalize proteins and modulate their proteolysis. Nevertheless, gaps in understanding the digestive fate of Maillard reaction products (MRPs) still exist, especially regarding bioactive proteins such as lactoferrin (LF). UV absorbance and SDS-PAGE were used to monitor reaction progression under mild thermal processing (60 °C, 79% RH). Dynamic light scatteringshowed that MRPs had increased colloidal size and turbidity at 3 < pH < 10. FRAP analysis and in vitro digestion experiments demonstrated that MRPs possessed improved antioxidant capacity and higher susceptibility to proteolysis to varying extents under adult conditions compared to infant conditions. Proteomic analyses of MRP digesta revealed altered enzymatic cleavage patterns with no pronounced changes in the formation of known bioactive peptides. These also indicated that MRPs may breakdown in the gastro-intestinal tract to potentially form novel bioactive peptides. Overall, this work highlights that the Maillard reaction could be harnessed to modify the extent of proteolysis and bioactivity of proteins