Jul 2026· Journal of Dairy Science· 0 citations· 34 references
Medicine
Abstract
Milk protein concentrate (MPC) is widely used in high-protein foods. However, increasing protein content often leads to undesirable functional and sensory attributes in the finished products. Interactions between whey proteins and caseins during heat treatment play a critical role in determining the structure and functionality of high-protein systems. In this study, a modified MPC containing caseins and preaggregated whey proteins was evaluated for its impact on acid-induced gelation. A model MPC was prepared by blending micellar casein concentrate (MCC) and milk whey protein isolate (mWPI) to achieve an 80:20 casein-to-whey ratio and was considered as the control MPC. Preaggregated whey proteins were produced by heating mWPI at pH 3.0 or pH 7.0 under constant shear, followed by adjusting the pH back to 6.8 and subsequently blending it with MCC. Heating mWPI at pH 7.0 resulted in significantly larger pre-aggregates (87.48 ± 3.22 nm) than heating at pH 3.0 (74.36 ± 1.33 nm; P < 0.05). After readjustment to pH 6.8, samples heated at pH 3.0 exhibited significantly higher viscosity (13.28 ± 0.98 mPa·s) and larger mean particle size (1580.34 ± 25.30 nm) compared with those heated at pH 7.0 (7.52 ± 0.53 mPa·s; 99.4 ± 9.86 nm). During acid-induced gelation, modified MPC containing whey proteins preaggregated at pH 3.0 showed a longer gelation time (25 min) and lower maximum storage modulus (1394.35 ± 62.15 Pa) compared with samples containing pre-aggregates formed at pH 7.0 (9 min; 2117.08 ± 15.59 Pa). These results demonstrate that pre-aggregation conditions of whey proteins strongly influence casein-whey interactions, viscosity, and gelation behavior. The new ingredients can potentially help in the development of a wide range of high-protein products, such as low viscosity drinkable yogurt, yogurt with reduced graininess. Overall, modified MPC containing preaggregated whey proteins shows potential as a functional ingredient for tailoring the rheological and structural properties of high-protein dairy systems.
Introduction: Functional properties and coating behaver of a whey proteins modified with citric acid were investigated. Objective: Citric acid modification was carried out by incubating whey protein with 0.67 mol/L citric acid at 50°C for 4 hours. Methods: The functional properties assessment demonstrated that citric acid alteration had a considerable impact on protein behavior. Solubility dropped significantly across all pH values (3-10), notably at pH 3-4, due to lower surface charge from crosslinking. Foaming capabilities and emulsifying activity index were similarly reduced. Results: The effect of using modified whey proteins as a coating material on potato strips properties was studied. Potato strips coated with 5% modified whey proteins had the maximum moisture retention (72.8%) compared to the uncoated control (62.3%) and dramatically reduced oil content to 10.32%, a 70.6% reduction over the control (35.1%). Conclusion: Texture study revealed that the 5% modified coating generated softer potato strips. Sensory test found that samples coated with 5% modified protein had the highest overall acceptability scores, combining health advantages (lower fat) with a pleasurable eating quality.
Graphical Abstract
Anaam S. Al-khafaje, J. Al-Saadi· International Journal of Nut...· 0 citations
Cheese whey is a large-scale by-product of milk processing, characterized by high biological value. However, its irrational use can lead to a serious environmental burden. One of the ways to solve this problem is the isolation of proteins and their fractionation, the efficiency of which significantly depends on the method used. In this work, a comparative assessment of four methods of processing reconstituted cheese whey (6.0 % dry matter mass fraction) was carried out, such as chitosan precipitation (pH 4.5; 20 °C; 1 % gel; 20 min), thermal acid coagulation (pH 4.65; 90 °C; 15 min) using lactic, citric, phosphoric and hydrochloric acids, cryo-acid precipitation (pH 4.5; –18 °C; 24 h) and ultrafiltration (spiral membranes with a cutoff threshold of 10 kDa). The study determined the proportion of precipitated protein, the fractional composition of soluble nitrogenous compounds using gel filtration, and specific operating costs. Ultrafiltration provided the highest efficiency of protein separation (65.92 ± 0.59 %), which also turned out to be an order of magnitude cheaper (≈112 rubles/m3) than all chemical methods. Among the thermal acid options, citric (57.83 ± 0.51 %) and hydrochloric (56.63 ± 0.55 %) acids proved to be the most effective. Chitosan and cryo-acid treatment showed low overall efficiency (26.51 ± 0.20 % and 25.30 ± 0.15 %, respectively). Analysis of the fractional composition of the supernatant showed that thermal acid coagulation and ultrafiltration completely removed β-lactoglobulin and BSA. Chitosan precipitation preserved the native profile of all major whey proteins, removing only ballast impurities. The cryoacid method demonstrated unique selectivity, virtually completely removing peptides while preserving native α-lactalbumin and β-lactoglobulin. A step-by-step fractionation strategy is proposed: treatment with chitosan to remove impurities, cryoacid separation of peptides, followed by isolation of native proteins by ultrafiltration or the thermal acid method.
D. Mamykin, O. Shukhalova, T. Volkova et al.· Food systems· 0 citations
Modulation of starch digestibility in ternary systems involving starch, lipids, and proteins is an emerging research area. However, native soy protein isolate (SPI) restricts the formation of wheat starch (WS)-lauric acid (LA)-protein complexes because of its rigid globular structure. Therefore, this study investigated the impact of SPI modified via pH-shift (pHS), ultrasound (US), and high-pressure microfluidisation (HPM) on the characteristics and structure of the WS-LA system. The results showed that the WS-LA-protein systems containing modified SPI exhibited increased cooling peak viscosity, higher resistant starch (RS) and slowly digestible starch (SDS) contents, and more complexes with greater short-range order than those systems containing SPI. HPM-modified SPI increased SDS content in the WS-LA-protein systems by 41.0%, promoted denser complexes, increased relative crystallinity by 21.4%, and enhanced short-range order compared with SPI. These findings provide a theoretical basis for formulating functional foods with controlled starch digestibility.
Jing Du, Jing Zhou, Jialun Zhang et al.· Food Chemistry· 0 citations
Citral is often used as a flavoring agent in food, beverages, and cosmetics. It deteriorates during storage due to its susceptibility to oxygen and acidic pH. In this work, we examined the influence of protein type, pH, and ratio on citral nanoencapsulation. To achieve this objective two protein types, whey protein concentrate (WPC) and skim milk (S), were used to nanoencapsulate citral via complex coacervation. Response surface methodology (RSM) using a Box-Behnken design optimized pH, protein type, and ratio. The maximum desirability was observed in 4% WPC and 1% carrageenan at pH 3. Different pH values (3, 6, and 9) were used for post-optimization characterization of the freeze-dried optimized formulation. The encapsulation efficiencies ranged from 64% to 35%, depending on pH. SEM results of citral-loaded nanocomplexes confirmed that the nanocapsules were spherical without holes under acidic conditions. These findings suggest that WPC-carrageenan complex coacervation is a promising approach for citral nanoencapsulation and may improve its applicability in food systems.
Pre-velveting foods suffer from significant flavor loss and limited shelf life during storage, motivating a demand for multifunctional starch-based carriers. To address this, corn starch (CS)-soy protein isolate (SPI) coacervates with varying CS ratios were fabricated to encapsulate fennel essential oil (FEO), yielding a pre-velveting material with antimicrobial and flavor-enhancing properties. Results indicated that higher CS/SPI ratios (4,1 and 5,1) enhanced viscoelasticity and reduced particle size by forming a dense polysaccharide-protein network that inhibited FEO aggregation compared with the lower ratios. The resulting microcapsules (CSSP4 and CSSP5) similarly demonstrated improved DPPH radical scavenging capacity (59.49% and 56.15%, respectively) and enhanced thermal stability. SEM and XRD confirmed increased cross-linking of CS upon coacervation with SPI, which provided the basis for the improved encapsulation efficiency of FEO via the dense structure, while FTIR and molecular dynamics simulations indicated that this structure was primarily driven by hydrogen bonding and electrostatic interactions between CS and SPI, and the starch-protein interface was visualized. Electronic nose combined with GC-MS analyses identified anethole as the primary flavor compound of FEO microcapsules and showed that the stable structure delayed its release, with CSSP4 exhibiting the slowest release due to its higher density. Furthermore, among all formulations, CSSP4 showed the lowest TBARS values and pH increase, as well as the most favorable volatile profile and improved textural properties in cooked chicken cubes. This study presents a novel starch-based carrier designed to improve flavor retention and extend the shelf life of pre-velveting foods.
Hengpeng Wang, Yang Meng, Yiwei Jin et al.· Food Research International· 0 citations
This study aimed to optimize a refreshing whey-based pineapple beverage formulation and convert the optimized formulation into a shelf-stable powder by spray-drying. Whey was produced from milk by heating (85°C for 5 min), coagulation (1.0 % citric acid), filtration, and centrifugation, while pineapple-juice was extracted, filtered, and pasteurized. Whey, juice, and beverages were characterized for physicochemical and functional properties. Whey contained TSS 8.0°B, pH 6.00, 0.77% protein, 4.78% lactose, 0.21% acidity, and TPC 6.39 mg GAE/100 mL, whereas pineapple-juice showed TSS of 10.3°B, pH 3.8, 0.58% acidity, 12.38% carbohydrates, and 84.86% moisture. Increasing pineapple juice (10 to 50%) decreased beverage protein (0.69-0.39%) and pH (5.78−1.90) while increased acidity (0.247–0.395%) and TSS (8.23–9.15°B). 70:30 whey-pineapple formulation achieved the highest overall-acceptability (8.0). This formulation was spray-dried with maltodextrin (2.5–7.5%), inlet-air temperature (150–170°C), and feed-flow (6–10 mL/min) using 17-run BBD to optimize yield, moisture, solubility, and bulk-density. The responses varied as 37.63–46.79% yield, 2.28–4.39% moisture, 91.54–99.04% solubility, and 0.27–0.401 g/cm
3
bulk-density; quadratic-models were highly predictive (R
2
≈0.984–0.996). Optimal conditions (169°C, 6.6% maltodextrin, 10mL/min) produced powder with 44.84% yield, 3.58% moisture, 97.6% solubility, and 0.393g/cm3 bulk-density, supporting whey valorization into instant beverage-powder with improved handling and potential nutritional utility.
A. Ghorband, Shahaji Kadam, Ditimoni Dutta et al.· BIO Web of Conferences· 0 citations