Whey Protein Products Research Articles

N- and O-Glycosylation of a Commercial Bovine Whey Protein Product

Bovine whey protein products are used as a base ingredient in infant formulas to optimize the amino acid pattern to a more human-like composition. Although the protein composition of bovine milk has been studied in detail, glycosylation details of commercial whey protein products are missing. To this end, both the N- and O-glycans of such a protein concentrate were sequentially released, the N-glycans enzymatically and the O-glycans chemically (reducing and nonreducing conditions). For the structural analysis of the N- and O-glycans a combination of MALDI-TOF-MS, one-dimensional (1)H NMR spectroscopy, Wisteria floribunda agglutinin affinity chromatography, HPAEC-PAD profiling, and HPLC-FD profiling (2-aminobenzamide derivatives), together with exoglycosidase treatments, were used. A mixture of over 60 N-glycans and 10 O-glycans was characterized, giving a detailed insight into the glycosylation of a bovine whey protein product, Deminal 90, which is applied as an ingredient for infant formulas.

Chymotrypsin selectively digests β-lactoglobulin in whey protein isolate away from enzyme optimal conditions: Potential for native α-lactalbumin purification

The present study examines the resistance of the α-lactalbumin to α-chymotrypsin (EC 3.4.21.1) digestion under various experimental conditions. Whey protein isolate (WPI) was hydrolysed using randomised hydrolysis conditions (5 and 10% of WPI; pH 7.0, 7.8 and 8.5; temperature 25, 37 and 50 °C; enzyme-to-substrate ratio, E/S, of 0.1%, 0.5 and 1%). Reversed-phase high performance liquid chromatography (RP-HPLC) was used to analyse residual proteins. Heat, pH adjustment and two inhibitors (Bowman-Birk inhibitor and trypsin inhibitor from chicken egg white) were used to stop the enzyme reaction. While operating outside of the enzyme optimum it was observed that at pH 8.5 selective hydrolysis of β-lactoglobulin was improved because of a dimer-to-monomer transition while α-la remained relatively resistant. The best conditions for the recovery of native and pure α-la were at 25 °C, pH 8.5, 1% E/S ratio, 5% WPI (w/v) while the enzyme was inhibited using Bowman-Birk inhibitor with around 81% of original α-la in WPI was recovered with no more β-lg. Operating conditions for hydrolysis away from the chymotrypsin optimum conditions offers a great potential for selective WPI hydrolysis, and removal, of β-lg with production of whey protein concentrates containing low or no β-lg and pure native α-la. This method also offers the possibility for production of β-lg-depleted milk products for sensitive populations.

Exopolysaccharides modify functional properties of whey protein concentrate

The objective of this research was to produce whey protein concentrate (WPC) with modified functionality using exopolysaccharide- (EPS) producing cultures. Two different EPS-producing cultures, Lactococcus lactis ssp. cremoris JFR and Streptococcus thermophilus, producing EPS1 and EPS2 respectively, were used in this study. One EPS-nonproducing commercial cheese culture (DVS 850; Chr. Hansen, Milwaukee, WI) was used as the control. Reconstituted sweet whey powder was used in this study to eliminate variations from fresh whey. Cultures grown overnight in reconstituted WPC (10% wt/vol) were added, directly or after overnight cooling (cooled EPS), at 2% (wt/vol) to 6% (wt/wt) solution of reconstituted whey. Whey was then high-temperature, short-time pasteurized at 75°C for 35s and ultrafiltered to a volume reduction factor of 5. Ultrafiltered whey (retentate) was spray dried at inlet and outlet air temperatures of 200 and 90°C, respectively, to obtain WPC. In general, the solubility of WPC was higher at pH 7 than at pH 3. Whey protein concentrate containing EPS2 exhibited higher protein solubility than did WPC containing no EPS. Also, the presence of EPS in WPC decreased protein denaturation. The emulsifying ability of WPC containing EPS was higher than that in control. Addition of EPS to WPC significantly enhanced its gelling ability. Foam overrun and hydrophobicity of WPC were not affected by addition of EPS. In conclusion, data obtained from this study show that EPS modify WPC functionality. The extent of modification depends on the type of EPS. Cooling of culture containing EPS before its addition to whey further reduced WPC protein denaturation and increased its solubility at pH 7 and gel hardness.

Effect of composition of commercial whey protein preparations upon gelation at various pH values

The major goal of this research effort was to comprehensively characterize various whey protein products available in the market — including one whey protein isolate (WPI) and three whey protein concentrates (two forms of WPC 80, and WPC 50), with regard to the effects of specific components (e.g. lecithin and minerals) and concentration of β-lactoglobulin (β-Lg) and α-lactalbumin upon thermal and gelation properties at various pH values (using micro differential scanning calorimetry, μDSC, and oscillatory rheometry). At pH values far from the isoelectric point of whey proteins, denaturation and aggregation appeared as one single endothermic peak in the corresponding μDSC heating thermograms, for WPI and both WPC 80; however, they appeared as separate transitions at pH 5. Acidic conditions increased the temperature of occurrence of the dominant endothermic transition associated to β-Lg, thus increasing the thermal stability of WPI, WPC 80A and WPC 80B. Gelation took place at the lowest temperature when pH was set at 5. WPI, WPC 80A and WPC 80B exhibited the highest G′ values at pH 5 — whereas WPI led to stronger gels than WPC, irrespective of pH. In the case of WPC 50, gelation did not occur at all.

Fluorescence spectroscopy and molecular modeling investigations on the thermally induced structural changes of bovine β-lactoglobulin

Abstract The heat-induced conformational and structural changes in β-lactoglobulin were analyzed using the fluorescence techniques and the molecular modeling approach. The experimental results confirm a two-state model for heat-induced changes of β-lactoglobulin at pH 6.5. The heat treatment at temperatures higher than 70 °C caused an increase in both intrinsic and ANS fluorescence intensity. The addition of quenching agents was employed to discriminate the fluorescence contributions of the two tryptophan residues of β-lactoglobulin (Trp 19 and Trp 61 ). The addition of acrylamide and KI causes an increase of the quenching constants associated with Trp 19 . This effect is observed at all temperatures studied, but the effect is stronger at temperatures higher than 70 °C. The heat-induced changes in the secondary and tertiary structure were outlined after running molecular dynamics simulations at different temperatures and neutral pH, therefore supporting the experimental observations. Industrial relevance In the food industry, one of the major concerns of whey processors is to produce whey protein products (such as whey protein concentrates or isolates as well as fractions enriched in β-lactoglobulin or α-lactalbumin) with specific functionalities. In this sense, the potential use of β-lactoglobulin as a supplement for special food products has encouraged the study of its physico-chemical and biological properties.

Effects of Liquid Whey Protein Concentrate on Functional and Sensorial Properties of Set Yogurts and Fresh Cheese

The production and incorporation of liquid whey protein concentrates (LWPCs) in fresh cheese and set yogurt is proposed as a solution for immediate reutilization of whey produced by small- and medium-scale dairy plants avoiding expensive processing steps (e.g., evaporation and drying) for the recovery of this by-product. Accordingly, the incorporation of LWPCs in such products was performed in order to compare the functional and sensorial properties of modified products with the conventional ones. The use of LWPC in fresh cheese increased water-holding capacity as well as product stability during storage. Fresh cheese hardness, chewiness, and gumminess decreased during storage in a more pronounced way in products with LWPC. The fat content influences significantly all the physicochemical properties tested in set yogurts. Incorporating LWPC in set yogurts does not produce appreciable differences in the visual properties when considering products with medium-fat content, but these differences become significant for full-fat yogurts. Adhesiveness and springiness were not significantly affected with storage time or by the amount of LWPC incorporated for medium-fat yogurts. Higher values of hardness and gumminess were obtained for full-fat yogurts, but these parameters decreased with LWPC incorporation. Syneresis was reduced using LWPC but increased with storage time. During storage, viscosity differences between LWPC incorporated yogurts and the conventional ones were only maintained in the case of creamy yogurts. The sensory panel detected differences between conventional and modified products in the case of fresh cheeses but no significative differences were detected between yogurts. LWPCs can be a good alternative to conventional dry products used in fresh cheese and set yogurt manufacture since their utilization reduces milk consumption and allows for the increase in total solids content. Additionally, their incorporation in milk originates end products with attractive physicochemical and sensorial characteristics at lower production costs.

Cleaning protocols for organic microfiltration membranes used in premix membrane emulsification

Premix membrane emulsification (ME) has been used to produce mono-disperse emulsions under process conditions that reduce the mechanical stress of sensitive compounds such as proteins, which can increase the stability of encapsulated biocompounds, but can cause membrane fouling. An organic nylon microfiltration membrane used to produce stable oil/water (O/W) emulsions stabilized with whey protein has been cleaned with different concentrations of commercial cleaning agents (Derquim+, Tween 20, or sodium hydroxide) alone or in combination, under different operation modes, including circulating the agent in forward or backwash mode. The efficiency of the membrane cleaning process was assessed using water flux recovery, membrane surface characterization by attenuated total reflectance infrared microspectroscopy (ATR-IRMS) and by assessing the performance of the cleaned membrane in premix ME. The results show that the highest level of cleaning efficiency was obtained with Derquim+ circulating in backwash mode, followed by a combination of Derquim+ and NaOH at 50°C. It was found that regardless of the cleaning agent used, an increase in the concentration of the agent had a lesser effect on increasing water flux recovery than increasing backwash pressure. Nevertheless, the water flux recovery values obtained with the cleaning agents tested indicate that some foulants (oil and/or whey protein) were left on the membrane surface and inside the pores. It was found that the membranes could be reused in premix ME to produce whey protein stabilized O/W emulsions, but the fluxes obtained during the second emulsification were always lower than those obtained using a new membrane, although the droplet size diameter of the emulsions obtained with a cleaned membrane was similar to the one obtained with a new membrane, except for membranes cleaned with a combination of surfactant and NaOH. ATR-IRMS analysis confirmed that membranes cleaned using Tween 20 had some foulants, primarily oil, left on the surface. This study shows the feasibility of applying membrane cleaning to organic membranes employed in premix ME and the viability of reusing such membranes for emulsification purposes.

A newly designed enteral formula containing whey peptides and fermented milk product protects mice against concanavalin A-induced hepatitis by suppressing overproduction of inflammatory cytokines

We previously reported that whey protein derived from cow milk suppressed inflammation in a variety of animal models. We developed a newly designed enteral formula using peptides prepared from whey protein and fermented milk product and investigated its ability to suppress inflammation in concanavalin A-induced hepatitis in mice. C57BL/6 mice were fed a standard formula, AIN-93M, or enteral formula for 14 days, and then were intravenously administered concanavalin A. Inflammatory cytokines in plasma, liver, and spleen and markers of hepatic function in plasma were assessed at various time points. Livers were assessed for necrosis and apoptosis. After concanavalin A treatment, plasma aspartate aminotransaminase, alanine aminotransferase, TNF-α, IL-6, and IFN-γ levels were significantly lower in mice fed enteral formula than in those fed standard formula or AIN-93M. Liver TNF-α and IFN-γ, and spleen IL-6 and IFN-γ levels were lower in enteral formula-fed mice than in standard formula-fed mice 2 h after concanavalin A treatment. Necrosis and apoptosis were suppressed in the livers of enteral formula-fed mice. The new enteral formula is a potent novel immune-modulating diet that prevents aggravation of local inflammation by modulating systemic cytokine levels.

Behavior of Protein in the Presence of Calcium during Heating of Whey Protein Concentrate Solutions

The effect of added CaCl(2) on heat-induced changes in whey protein (WP) solutions prepared from whey protein isolate (WP1), acid whey protein concentrate (WP2), and cheese whey protein concentrate (WP3) was investigated. The loss of native-like, proteins, aggregation, and gel firmness of WP were maximum at certain levels of added CaCl(2). These levels were different for different WP products. The effect of added CaCl(2) on these changes appeared to be related to the initial calcium concentrations of these solutions. The higher the calcium content of the product, the less available sites for added CaCl(2) to bind. It was considered that addition of CaCl(2) changed the types of protein interactions that formed the protein aggregates during heating. Added calcium caused dramatic decreases in fracture stress of WP gels due to the formation of large protein aggregates.

Straightforward Process for Removal of Milk Fat Globule Membranes and Production of Fat-free Whey Protein Concentrate from Cheese Whey

A straightforward method for the separation of milk fat globule membrane (MFGM) and production of fat-free whey protein concentrate/isolate from cheese whey has been developed. Lowering of the conductivity of the whey from its initial value of about 5600 μS cm(-1) to about 2000-500 μS cm(-1) via diafiltration with water caused selective precipitation of MFGM when incubated for 30 min at pH 4.2 and 35 °C. The whey proteins remained soluble in the supernatant under these conditions. Experimental evidence suggested that precipitation of MFGM at pH 4.2 was not due to a nonspecific effect of lowering of the conductivity of the whey but due to the specific effect of removal of Ca2+ from the whey. The lipid content of whey protein isolate obtained by this process was <0.2%, and the protein loss was <14%. The method provides an industrially feasible process for the production of fat-free whey protein concentrate/isolate. The MFGM, which is reported to contain bioactive/nutraceutical lipids and proteins, is a valuable byproduct of the process.

Investigations of Effects of Cooper Ion on the Allergenicity of β-Lactoglobulin

β-lactoglobulin (BLG), the most abundant whey protein in milk, governs the overall process-induced aggregation and gelation of whey protein products. BLG industrial application can be limited due to its high allergenicity. Here, we attempt to obtain new views from inducing of aggregation and then reducing allergenicity of BLG upon interaction with cooper ions. The effect of Cu+2 on the structure of BLG as the carrier model protein was investigated using UV-Visible, fluorescence and circular dichroism (CD) spectroscopy instruments at different temperatures of room and physiologic. Results of UV-Visible studies represent that adding Cu+2 to BLG solution caused increasing of turbidity in the protein solution. It is noticeable that rate of increasing turbidity is higher at upper temperature. Fluorescence studies revealed that Cu+2 can quench the intrinsic fluorescence emission of the protein at different temperatures. The far-UV CD studies displayed that Cu+2 cannot induce any changes in the secondary structures of BLG at different temperatures. The results highlight that copper ions affect the tertiary structure to change and induce slightly open structure lead to formation of supramolecular aggregates in BLG. Also, it seems that inducing of aggregation in BLG upon interaction with cooper ions may be responsible for the disappearance of conformational epitopes or masking effect on the recognition of epitopesand consequently, which reduced allergenicity of BLG.

Lowering the Maillard reaction products (MRPs) in heated whey protein products and their cytotoxicity in human cell models by whey protein hydrolysate

This study investigated the potential use of reconstituted whey protein hydrolysate as an antibrowning agent in thermally processed foods and as a chemopreventive ingredient in biological systems. Hydrolysates were prepared by tryptic (EC 3.4.21.4) hydrolysis of whey protein concentrate (WPC) or heated (80 °C for 30 min) whey protein concentrate (HWPC). Tryptic hydrolysis of WPC and HWPC increased the oxygen radical absorbance capacity-fluorescein (ORAC FL) antioxidant capacity from 0.2 to 0.5 μmol Trolox equivalent (TE)/mg protein in both whey protein hydrolysate (WPH) and heated whey protein hydrolysate (HWPH) ( p < 0.05). The reconstituted WPH and HWPH could prevent the formation of Maillard reaction products (MRPs) induced by a thermal process employed on WPC suspensions between 80 and 121 °C in the presence of lactose up to 0.25 M ( p < 0.05). The MRPs in HWPC were cytotoxic to both normal human intestinal FHs 74 Int cells and human epithelial colorectal carcinoma Caco-2 cells. The IC 50 of HWPC was around 3.18–3.38 mg/mL protein. Nonetheless, when both cell types were grown in media supplemented with WPH prior to the uptake of MRPs in HWPC at 3.5 mg/mL, they were able to survive ( p < 0.05). Overall, this study indicated the efficacy of WPH and HWPH in the prevention of MRP cytotoxicity. It was suggested that the ORAC FL antioxidant capacity of WPH and HWPH needed to be high enough to provide a chemopreventive effect against MRP cytotoxicity.

Reducing the antigenicity of milk whey protein using acid proteinases from Monascus pilosus

Recently, we purified two acid proteinases (MpiAP1 and MpiAP2) from Monascus pilosus. In this study, we examine the potential application of these enzymes in the production of low-antigen whey protein. Hydrolysates of whey protein concentrate (WPC) were prepared enzymatically using MpiAP1, MpiAP2, pepsin and trypsin, both singly, and in combination. The electrophoretic analyses of WPC degradation showed that casein is the component most favored by all enzymes. The α-lactalbumin was completely digested by fungal acid proteinases but not by gastrointestinal proteinases, and β-lactoglobulin was effectively digested by trypsin only. The complete digestion of all WPC components was accomplished with the addition of trypsin to partially hydrolyzed WPC treated with Monascus acid proteinases. The lowest antigenicity was observed in the WPC hydrolysates treated with MpiAP1/MpiAP2 and trypsin by competitive ELISA. Our results suggest that Monascus acid proteinases can be effectively used to make hypoallergenic bovine milk whey protein hydrolysates.

Recent Patents on Whey Protein Hydrolysates Manufactured by Proteolysis Coupled to Membrane Ultrafiltration

For many years protein hydrolysates have been used in the food industry due to ability to modify the functional properties of proteins, mainly solubility, emulsifying and foaming features, flavour, etc. More recently, protein hydrolysates are incorporated as food ingredients in energy-providing drinks, hypoallergenic formulae, enteral diets for children and clinical nutrition. To this end, the nutritional properties are improved in comparison with native proteins. Among the various protein sources (soy, wheat, egg, haemoglobin, etc.) whey proteins are outstanding due to their high nutritional value, low bitterness (depending on the enzymatic process) and low antigenicity. Finally, whey protein hydrolysates constitute an excellent source of bioactive peptides, showing anti-hypertensive, immunological or antimicrobial activity, for instance. With respect to the manufacturing of whey protein hydrolysates, the enzymatic bioconversion processes are of increasing use in the production, transformation and valorisation of protein raw materials. Predominantly, industrial production is carried out in a classical batch reactor at controlled temperature. At the end of the reaction the enzyme is inactivated and remains into the final product. However, there are several disadvantages associated to this method, the high enzyme consumption being the main one. Hence, alternative operational procedures have been proposed, mainly enzyme immobilisation onto supports and the use of ultrafiltration membranes. Thus, membrane ultrafiltration of whey protein hydrolysate is aimed at: i) fractionating the hydrolysate in order to adjust its functional and nutritional properties, ii) remove the enzyme from the final hydrolysate and iii) recover and reuse the enzyme in further reactions if possible. Whey protein hydrolysates have received much attention after the Second World War (SWW). Patents dealing with whey protein hydrolysates have been issued regularly, particularly during the 1970s. Initially, the scope of such patents was to produce whey protein hydrolysates as food modifiers (improving protein solubility, providing emulsifying or foaming ability, etc.). During the 1980s and 1990s, patents were focused on reducing the antigenicity of proteins. For this purpose, it is essential to control the characteristics of the final hydrolysate. Hence, membrane technologies were used to obtain selected fractions and remove undesirable substances like free amino acids or non-reacted native proteins. Finally, selected peptides released during enzymatic degradation of proteins may regulate biological processes like hypertension mechanisms, immune reactions, etc. Thus, the manufacturing of bioactive peptides is a new research area and a number of recent patents have been published. In this article, a comprehensive review of the patents dealing with the enzymatic processes, membrane technologies and applications of whey protein hydrolysates is provided. Keywords: Whey protein, protein hydrolysates, membrane ultrafiltration, enzymatic proteolysis

Properties of Extrusion-Expanded Whey Protein Products Containing Fiber

Three insoluble dietary fibers (cellulose, wheat, and oat) were incorporated into an extruded-expanded product containing 32% whey protein at three concentrations (18, 36, and 48%) to determine the influence of fiber on extrudate properties. As the concentration of fiber in the extrudates increased, there was a significant decrease in expansion ratio, air cell size, water soluble carbohydrate, and water solubility index, and a significant increase in extrudate density, breaking force, moisture content, and water absorption index. The main effects observed were attributed primarily to a decrease in the amount of normal cornstarch.

Microemulsions as Nanoreactors To Produce Whey Protein Nanoparticles with Enhanced Heat Stability by Sequential Enzymatic Cross-Linking and Thermal Pretreatments

Sequential enzymatic cross-linking and heat pretreatments were used in this work to enhance the heat stability of whey protein isolate (WPI). In the first route, WPI was cross-linked by transglutaminase before incorporation in microemulsions for heat pretreatment at 90 degrees C for 20 min. In the second route, WPI was cross-linked by transglutaminase within microemulsions before thermal pretreatment. Particles produced from the two routes were different in dimension and heat stability and were also affected by the ratio of WPI and enzyme and cross-linking duration. At appropriate conditions, for example, 10 h of cross-linking by transglutaminase equivalent to 5% mass of WPI using the first route, a 5% dispersion (pH 6.8 and 100 mM NaCl) of the produced nanoparticles remained clear after heating at 90 degrees C for 20 min. In comparison, nanoparticles produced by thermal pretreatment only in a microemulsion corresponded to a translucent, flowable dispersion, whereas native WPI formed a gel. This novel approach can be used to manufacture heat-stable whey protein ingredients for clear beverage applications.

Comparison of 3DTA and VSEP systems during the ultrafiltration of sweet whey

Whey, a side-product of the cheese-making and casein industry, is a nutritious protein source. The nutritional, biological and functional properties of whey proteins make them attractive and explain why an active whey industry has been developing over the last 30 years. The preconcentration of whey at its production site is the major field of application of membrane separation. The high salt content of whey (8–20% dry matter) gives rise to numerous processing difficulties, a low lactose crystallization rate, and fouling in microfiltration (MF) and ultrafiltration (UF) performed to produce whey protein concentrates. In order to improve UF performance, it is advisable to limit fouling of the membranes by selecting an appropriate flux or shear stress ratio [1]. In this study, the performance of a vibratory shear-enhanced processing system (VSEP) for the concentration of cheese whey was assessed and compared with a classical, cross-flow, plate and frame membrane configuration system (3DTA) with the same membrane (i.e. a C30F UF regenerated cellulose UF membrane with a 30 kDa molecular mass cut-off). The temperature and pressure dependences of the permeate flux, the permeate flux reduction ratio, the resistances and the rejection values were investigated. Comparison of the two systems revealed a definite advantage for the VSEP system equipped with the same membrane and operated at the same pressure and temperature. The flux reduction ratio (J/J0) was 0.60 vs. 0.42, and the total resistances 2.87×1013 m-1 vs. 4.54×1013 m-1 for the VSEP and 3DTA system, respectively.

EFFECT OF FERMENTED WHEY PROTEIN CONCENTRATE ON TEXTURE OF IRANIAN WHITE CHEESE

ABSTRACT The influence of fermented whey protein concentrate (FWPC) added before and after formation of cheese curd on the textural characteristics of Iranian white cheese was studied. The FWPC, prepared from whey obtained during cheese making, was added at different levels 5, 10, 15 and 20% (v/v) after (A) or before (B) cheese curdling. The changes in rheological parameters of cheeses were determined before and after 1 month of ripening. It was found that both incorporation level and stage of addition of FWPC (A and B) caused significant effects on texture profile analysis of cheeses. Increasing the level of FWPC in B group, except samples containing 10% FWPC, in contrast with A cheeses led to considerable increase in moisture and decrease in hardness and chewiness. Samples containing more than 15% FWPC had undesirable texture and were too soft. All experimental cheeses exhibited a decline in values for each rheological parameter after 1 month of ripening. PRACTICAL APPLICATIONSPerhaps the biggest story in the dairy industry in the past couple of decades has been the rise of new applications for whey and whey proteins. Once considered a waste product in the cheese manufacturing process, whey and whey protein products today are used for a wide range of functional and nutritional properties. In the cheese industry, particularly in soft cheese varieties, whey proteins have shown good applications to replace caseins as they act as fat replacer and bind more water than caseins, which results in softer cheeses. Therefore, this study was attempted to investigate the impact of fermented whey protein concentrate on textural attributes of Iranian white cheese.

Microemulsions as nanoreactors to produce whey protein nanoparticles with enhanced heat stability by thermal pretreatment

Native whey proteins (NWPs) may form gels or aggregates after thermal processing. The goal of this work was to improve heat stability of NWPs by incorporating protein solutions in nanoscalar micelles of water/oil microemulsions to form whey protein nanoparticles (WPNs) by thermal pretreatment at 90 °C for 20 min. The produced WPNs smaller than 100 nm corresponded to a transparent dispersion. The WPNs produced at NWP solution pH of 6.8 had a better heat stability than those produced at pH 3.5. The salt concentration (0–400 mM NaCl) in NWP solutions did not significantly change the size of corresponding WPNs. Compared to NWPs, the 5% (w/v) dispersion of WPNs at pH 6.8, 100 mM NaCl did not form a gel after heating at 80 °C for 20 min. The improved heat stability and reduced turbidity of WPNs may enable novel applications of whey proteins in beverages.

Factors Affecting the Functional Properties of Whey Protein Products: A Review

Numerous why protein products (WPP) have been developed as excellent food ingredients with unique functional properties. However, the functional properties of WPP are affected by several compositional and processing factors. Recently, novel processing technologies such as high hydrostatic pressure, ultrasound, extrusion and tribomechanical activation have been used to modify the functional properties of WPP. Also, WPP have been used as delivery systems for functional ingredients and in edible films. The present paper reviews the latest developments in the role of different factors on the functional properties of WPP with emphasis on novel processing technologies, and interaction with other food ingredients