Combination of κ-сarrageenan and gum arabic for thickening liquid whey protein concentrate.

The thickening properties of κ-carrageenan and gum arabic for a liquid concentrate of acid whey proteins obtained by nanofiltration (nanofiltrated concentrate – NF concentrate) have been investigated. The samples of NF concentrate have been enriched with a concentrate of milk whey proteins with a protein mass fraction of 80% in the dry matter and maltodextrin with a dextrose equivalent of 20%. As a result, the total solids content in the created systems was 36.37%. Titrable acidity of the initial serum and NF concentrate has been determined by the indicator titration method. Actual acidity of samples enriched with whey protein and maltodextrin has been determined by the potentiometric method. Physicochemical parameters of raw materials and product samples have been analyzed by the instrumental expression method using the MilkoScan FT 120 infrared analyzer and the Bruker MPA spectrometer. The calcium content has been determined by the complexometric method, vitamin C – by indicator method with 2.6-dichlorophenolindophenol. The consistency of the product samples has been assessed visually. The viscosity has been determined by rotational viscometry. The dispersion of the systems has been investigated by the method of interference-polarization microscopy. The combination of κ-carrageenan and gum arabic transformed the system from a sol state to a gel. After after 7 days of storage at 4±2 °C the viscosity of samples containing 0.3% κ-carrageenan and 0.2% gum arabic was 42793 MPa·s, in samples containing 0.2% κ-carrageenan and 0.3% gum arabic – 59910 MPa·s. All samples had insufficient thermal stability, since they softened at 20±2 °C. Gum arabic gave the samples signs of a whipped structure. The dispersion of the air phase was finer with a content of 0.2% gum arabic. [ABSTRACT FROM AUTHOR]