Reducing the stiffness of concentrated whey protein isolate (WPI) gels by using WPI microparticles

Liquid Whey Protein Concentrates Produced by Ultrafiltration as Primary Raw Materials for Thermal Dairy Gels

“…These include the protein type (molecular mass and amino acid composition) (6), protein hydrophobicity and free sulphydryl groups (7), protein concentration (8), the proportions of individual whey proteins in the mixture (9), the type and amount of salts (8,10,11), lipids (12), lactose (6), sucrose (13) present in the formula-tion, process conditions (pH, temperature, heating and cooling rate) (14,15), and/or specific treatments such as microparticulation of whey proteins (16)(17)(18). Among these factors, attention has been focused on protein concentration and pH.…”

Water-binding of protein particles

“…This amount of water was subtracted from the amount of water in the continuous phase, and the concentration in this phase was recalculated. This recalculation, using the data reported by Purwanti, et al (2012), [115] shows that water-binding by HG MPs can explain the small increase in strength of the continuous phase (Table 11). This suggests that only the absorption of water by HG MPs affected the strength of the continuous phase, and that our data on swelling of the HG MPs explain the data of Purwanti, et al (2012) [115] and .…”

“…This recalculation, using the data reported by Purwanti, et al (2012), [115] shows that water-binding by HG MPs can explain the small increase in strength of the continuous phase (Table 11). This suggests that only the absorption of water by HG MPs affected the strength of the continuous phase, and that our data on swelling of the HG MPs explain the data of Purwanti, et al (2012) [115] and . [116] In summary, it may be interesting to determine the behaviour (e.g., water division) of MPs and their pellets in (model) products to investigate their applicability.…”

“…At similar effective protein concentrations (i.e., "the protein concentration of the composite gel as if it contained only native WPI leading to a similar gel stiffness"), [115] it was reported that the strength of a gel with HG MPs was equal to that of a WPI gel, with a concentration between that of the continuous phase and the total protein concentration. The HG MPs would absorb some water, and therefore one would indeed expect the continuous phase to be stronger with HG MPs than without.…”

“…In case the water-binding properties of MPs can be controlled, they can be used to alter the water-binding properties of a full product by adding the particles as an additional dispersed phase. [115] [116] However, the possibilities to control the water-binding properties of MPs are not yet well understood. The Flory-Rehner model can be used to obtain guidelines on increasing the swelling capacity of MPs.…”