Whey Ingredients and Coproducts

Publications of interest

The impact of agglomeration and storage on flavor and flavor stability of whey protein concentrate 80 and whey protein isolate 

This study examined the impact of agglomeration on the flavor and flavor stability of commercial whey protein concentrates 80 percent (WPC80) and whey protein isolates (WPI) across 18 months of storage. Results indicate that the optimum shelf life at 21 C for nonagglomerated whey proteins is 12 to 15 months and eight to 12 months for agglomerated whey proteins.

The effect of bleaching agent on the flavor of liquid whey and whey protein concentrate

The increasing use and demand for whey protein as an ingredient requires a bland-tasting, neutral-colored final product. This study determined if bleaching alters the flavor of liquid and spray-dried Cheddar whey. Results show that bleaching liquid whey may affect the flavor of the spray-dried product. The type of bleaching agent also may affect flavor.

Moisture-induced aggregation of whey proteins

Authors discuss factors (irreversible moisture-induced protein aggregation, hydrophilic interactions and advanced Maillard reactions) that cause loss of functionality and nutritional value of whey proteins.

Glycosylation and expanded utility of a modified WP ingredient via carbo conjugation at low pH

This study determined that the functionality of a thermally treated whey protein concentrate ingredient can be enhanced by conjugating carbohydrate materials at low pH.

The effect of starter culture and annatto on the flavor and functionality of whey protein concentrate

The objective of this study was to evaluate the effect of annatto color and starter culture on the flavor and functionality of whey protein concentrate (WPC). The study determined that annatto has no effect on whey protein flavor, but the starter culture has a large influence on oxidative stability of whey.

Foams prepared from whey protein isolate and egg white protein: 1. physical, microstructural and interfacial properties

This study determined that foams made with egg white had higher yield stress and stability than foams made with whey protein.

Roles of charge interactions on astringency of whey proteins at low pH

This study compared the astringency of β-lactoglobulin (β-LG) at low pH with phosphate buffer controls having the same amount of phosphate and at similar pH. Results show that β-LG solutions are more astringent than phosphate buffers at similar pH and phosphate levels. Astringency is caused by acid and protein.

Role of protein concentration and protein-saliva interactions in the astringency of whey proteins at low pH 

This study evaluated the effects of protein concentration on astringency and interactions between whey and salivary proteins. Results show that astringency of whey proteins is determined by aggregation in the mouth and depends on beverage pH, buffering capacity and saliva flow rate.

Properties of extrusion-expanded whey protein products containing fiber

This study evaluated cellulose, wheat and oat in an extruded-expanded product containing 32 percent whey protein to determine influence of fiber on extrudate properties.

Optimizing the use of power ultrasound to decrease turbidity in whey protein suspensions

This research used power ultrasound to decrease the turbidity of whey suspensions. Results show nearly 90 percent decrease in turbidity when power ultrasound was applied to a whey suspension of 28.2 percent of solids containing 35.6 percent of protein on a dry basis.

Effects of polyols on the stability of whey proteins in intermediate-moisture food model systems

This study determined how polyols influence the stability of whey proteins in intermediate-moisture food systems and cause bar hardening in protein-based nutrition bars. Results show that propylene glycol should not be used in whey-protein-based, high-protein, intermediate-moisture foods because it changes the protein conformation and stability. These changes result in protein aggregation that hardens the bar texture during storage.

Invited review: annatto usage and bleaching in dairy foods

This paper discusses the advantages, disadvantages, regulatory concerns, flavor implications and optimum usage conditions of hydrogen peroxide and benzoyl peroxide, as well as lipoxygenase, peroxidase and lactoperoxidase systems.

Formation of elastic whey protein gels at low pH by acid equilibration

This study shows that whey protein isolate gels can be made at pH ≤ 4.5 with a strong/elastic fracture pattern and the magnitude of this pattern can be altered by varying the acid type, acid concentration, pH of equilibrating solution and equilibrating time.

Emulsifying properties of lactose-amines in oil-in-water emulsions

Lactose-amines were synthesized with hexadecyl-amide and lactose via the Maillard reaction, and their emulsion stabilization properties were investigated. Results show that lactose-amines synthesized with various heating conditions resulted in samples with emulsification activity.

Effects of sucrose on egg white protein and whey protein isolate foams: factors determining properties of wet and dry foams (cakes)

This study examined the effects of sucrose on the physical properties of foams, air/water interfaces, angel food of egg white protein (EWP) and whey protein isolate (WPI). Results show sucrose modifies bulk phase viscosity and interfacial rheology and improves the stability of wet foams.

Effect of protein on sorption characteristics of delactosed permeate

This study investigated the effects of protein on the characteristics of delactose permeate. Characteristics included moisture adsorption/desorption kinetics and glass transition temperature (those that influence drying and product stability after drying).

Effect of cysteine on lowering protein aggregation and subsequent hardening of whey protein isolate (WPI) protein bars in WPI/buffer model systems

This study investigated the effects of cysteine (Cys) on reducing hardening of whey protein isolates (WPIs) in protein bars. Results show that WPI bar hardening was significantly delayed by using lower molar ratios of cysteine/WPI (0.05) or N-ethylmaleimide/WPI (2.0) but was accelerated by higher molar ratios of cysteine/WPI (0.25).

Comparison of spice-derived antioxidants and metal chelators on fresh beef color stability

This study examined the effectiveness of antioxidants in preventing myoglobin oxidation and color loss in raw ground beef packaged in polyvinylchloride (PVC) overwrap. Results show that antioxidants such as milk mineral, eugenol and rosmarinate were effective at preventing oxymyoglobin oxidation and red color loss.

Comparison of composition and sensory properties of 80 percent whey protein and milk serum protein concentrates

This study identified and compared the composition, flavor and volatile components of 80 percent protein milk serum protein concentrates (SPC) and whey protein concentrates (WPC). Results show that beverages made with SPC ranked higher in aroma, appearance and mouthfeel compared with beverages made with WPC. Beverages made with SPC ranked lower in flavor and overall liking.

Effect of composition on moisture sorption of delactosed permeate

Delactosed permeate (DLP) is an effluent generated after proteins and lactose are separated from cheese whey. DLP is difficult to commercialize because it has a high moisture content and is an unstable ingredient. This study identifies the primary constituents in DLP with the most influence on the characteristic sorption behavior of DLP, which is responsible for its stickiness and hygroscopicity.

Cold-set thickening mechanism of β-lactoglobulin at low pH: concentration effects

This study looked at concentration effects on thermal aggregation of β-lactoglobulin at low pH using capillary and rotational viscometry, transmission electron microscopy (TEM) and high-performance liquid chromatography coupled with multi-angle laser light scattering (HPLC-MALS).

Moisture-induced aggregation of whey proteins in a protein/buffer model system

This study evaluated the molecular mechanisms and controlling factors for moisture-induced whey protein aggregation in a model system. These aggregates rapidly formed during the first three days of storage at 35 C with a slower rate afterward. Intermolecular disulfide bonds were the main mechanism for protein aggregation.

Formation of whey protein isolate (WPI)−dextran conjugates in aqueous solutions

This study investigated the conjugation reaction between whey protein isolate (WPI) and dextran in aqueous solutions via the initial stage of Maillard reaction.

Effects of moisture-induced whey protein aggregation on protein conformation, the state of water molecules and the microstructure and texture of high-protein-containing matrix

This study shows that whey proteins in a protein/buffer model system formed insoluble aggregates during three months’ storage at temperatures varying from 4 to 45 C, resulting in changes in microstructure and texture.

Characterization of textured whey protein produced at varying protein concentrations

This research investigated the range of whey protein in a whey protein/starch mixture needed to produce an extrusion-textured whey product that contained a fibrous texture. It was determined that protein levels ranging from 48 to 64 percent were necessary for fiber formation.

Charged ultrafiltration membranes for whey protein fractionation

This study examined the use of positively charged membranes to increase the selectivity of ultrafiltration (UF) and allow the fractionation of proteins from cheese whey. By adding a positive charge to UF membranes, and adjusting the solution pH, it was possible to permeate proteins having little or no charge, such as glycomacropeptide, and retain proteins having a positive charge.