Search Results (27)

The rapid expansion of high-protein dairy-based powders (HPDPs), including milk protein concentrates and isolates (MPC/MPI), whey protein concentrates and isolates (WPC/WPI), and micellar casein concentrates and isolates (MCC/MCI), has intensified the need to understand instability phenomena that emerge during processing and storage. These products are governed by protein-rich amorphous matrices, in which molecular mobility, interfacial composition, and mineral interactions dictate both physical stability and functional performance. Importantly, these physical instabilities are directly coupled with functional deterioration, particularly in terms of impaired wetting, dispersion, and dissolution during rehydration. This review presents an integrated mechanistic framework linking these instability phenomena across processing, storage, and reconstitution, thereby consolidating concepts that remain fragmented across the current literature on high-protein dairy matrices. Key controlling factors include glass transition temperature (Tg), water activity-induced plasticization, protein–protein and protein–mineral interactions, and surface compositional heterogeneity established during spray drying. These factors govern the progression from surface stickiness through uncontrolled agglomeration to caking, forming a consolidation continuum. In contrast to lactose-driven matrices, caking and agglomeration in HPDPs arise primarily from protein-mediated restructuring and inter-particle bonding, with lactose crystallization acting only as a secondary mechanism in mixed-composition grades. The review further distinguishes engineered agglomeration from storage-induced consolidation and evaluates advances in molecular mobility characterization and Tg-based stability mapping. Significant gaps remain in linking localized surface evolution, mineral redistribution, and inter-particle bridge chemistry under realistic environmental conditions. The review concludes by proposing a mobility-centered “stability-by-design” framework that integrates composition, processing, particle architecture, and storage conditions to guide the development of future HPDPs with improved physical stability and functional recovery. Full article

Background: Lactoferrin is a major functional protein involved in maintaining human health, which possesses antioxidant, anti-inflammatory, antibacterial, and antiviral properties. Therefore, it can be used to support the treatment of viral and bacterial diseases, as well as in cancer prevention. Lactoferrin-manufacturing processes may compromise its protein structure and function, so it is necessary to establish reliable analytical methods for production efficiency and quality control purposes. This paper reviews the lactoferrin production processes, summarising the methods using various matrices (milk, milk powder, infant formula, whey, bovine lactoferrin lyophilised powder, yoghurt, colostrum, and human milk), the most popular purification methods, and sample preparation. Material and methods: The Medline and Embase databases were searched using the following phrases: ”lactoferrin” and “purification” or “isolation” or “extraction” or “separation”. The search was limited to recent studies from the last five years published in English up until 12 March 2025. Of the 573 articles identified, 17 were reviewed. Results: Lactoferrin purification and determination methods depend on the matrix used. The latest research focuses on improving parameters of lactoferrin determination, shortening time, improving efficiency or limiting costs, and even reducing toxicity by changing the reagents. The method of separating lactoferrin using magnetic beads or nanoparticles has been developed, as well as the determination parameters using high-performance liquid chromatography (HPLC). Conclusions: The current lactoferrin production techniques are characterised by increased efficiency and quality, but they require standardisation of the purification process depending on the matrix. The latest Lf determination methods are highly precise, and most of them produce high-quality Lf. This allows to introduce on the market a higher quality product, which can significantly improve standard approaches. Full article

Protein constitutes the primary nutrient in soy, and its modifications are intricately linked to the properties of the soy milk powder. This study employed six main commercial enzymes (bromelain, neutrase, papain, trypsin, flavourzyme, and alcalase) to investigate the impact of enzymatic hydrolysis on the structural and functional properties of soy protein isolate (SPI), as well as its influence on the physicochemical properties of soy milk powder. The findings indicated that each of enzymes exhibits distinct specificity, with the degree of hydrolysis following the order: alcalase > flavourzyme > papain > bromelain > neutrase > trypsin. Enzymatic hydrolysis facilitates the unfolding of SPI, leading to the exposure of chromogenic fluorophores and hydrophobic amino acid residues, which in turn promotes an increase in free sulfhydryl content. Concurrently, this process induces the transformation of α-helix and β-sheet into β-turn and random coil. The enzyme modification enhances the solubility, emulsification, and foaming activities of SPI and significantly augment its antioxidant properties (p < 0.05). However, this enzymatic treatment adversely affects the stability of its emulsification and foaming properties. Subsequent to enzymatic hydrolysis, soy milk powder demonstrated a reduction in particle size and an improvement in solubility, which significantly enhanced its flavor profile. In summary, alcalase offers substantial advantages in augmenting the functional properties of SPI and increasing the solubility of soy milk powder. However, this process adversely affects the flavor profile of soy milk powder, a consequence attributed to the broad hydrolysis specificity of alcalase. Full article

The objective was to determine the digestible indispensable amino acid score (DIAAS) of food sources using the pig model and in vitro procedures. The standardized ileal digestibility (SID) of amino acids (AA) in white rice, wheat, pea protein concentrate (PPC), soy protein isolate (SPI), and skim milk powder (SMP) were determined in pigs. Twelve barrows with an initial body weight of 28.4 kg (standard deviation = 4.0) equipped with a T-cannula at the distal ileum were allotted to a replicated 6 × 5 incomplete Latin square design with six diets and five periods. Five experimental diets contained each ingredient as the only source of AA. Additionally, a nitrogen-free diet was prepared to measure the basal endogenous losses of AA for the calculation of the SID of AA. The in vitro ileal disappearance (IVID) of crude protein (CP) in the five food sources was also determined using the conventional flask procedure and the multi-sample simultaneous in vitro procedure employing the Daisy^II incubator. The DIAAS values for white rice were 42, 50, and 60 for infants, children, and adults, respectively. For wheat, the DIAAS values were 46, 56, and 66, respectively. The DIAAS values for PPC were 47, 58, and 69 for infants, children, and adults, respectively. For SPI, the values were 61, 74, and 87, respectively. The DIAAS for SMP were 82, 112, and 131 for infants, children, and adults respectively. The IVID of CP in SMP was greater (p < 0.05) than that in other sources. The DIAAS calculated based on IVID of CP were similar to those determined based on the SID of AA in pigs. In conclusion, white rice, wheat, pea protein concentrate, and soy protein isolate were observed to have DIAAS values less than 100, indicating that these ingredients need to be combined with other protein sources to meet the indispensable AA requirements. Skim milk powder had a DIAAS greater than 100 for children and adults. Full article

Electrostatic spray drying (ESD) of a milk protein matrix comprising whey protein isolate (WPI), skim milk powder (SMP), and lactose was compared to conventional spray drying (CSD) and freeze-drying (FD). ESD and CSD were used to produce powders at low (0.12–0.14), medium (0.16–0.17), and high (0.31–0.36) levels of water activity (a_w), while FD powders targeted low a_w (0.12). Maillard reaction indicators were studied after drying and during storage for up to 28 days at 20, 40, or 60 °C by measuring free -NH₂ groups, as an indicator of available lysine, and 5-hydroxymethylfurfural (HMF). After drying, levels of residual free -NH₂ groups were ~15% higher in ESD and FD powders than in their CSD counterparts. CSD powders also had ~14% higher HMF concentrations compared to their ESD and FD counterparts. Storage led to reductions in free -NH₂ groups and increases in HMF content in all powders, the extent of which increased with increasing storage temperature. Reductions in free -NH₂ groups followed first-order reaction kinetics at 20 and 40 °C but second-order reaction kinetics at 60 °C. Lactose crystallization was detected in high-a_w CSD powders after 14 d at 40 °C and in both CSD and ESD powders after 7 d at 60 °C. Overall, we found that ESD is a gentle drying technology which enables production of powders with lower Maillard reaction markers. Full article

The amino acid (AA) content of multiple samples of various dairy powders was determined, providing a comprehensive evaluation of the differences in AA profiles attributable to distinct manufacturing processes. Products examined included whole milk powder (WMP), skim milk powder (SMP), cheese whey protein concentrate (WPC-C), lactic acid casein whey protein concentrate (WPC-L), high-fat whey protein concentrate (WPC-HF), hydrolyzed whey protein concentrate (WPH), whey protein isolate (WPI), and demineralized whey protein (D90). WMP and SMP exhibited broadly similar AA profiles, with minor differences likely due to the minimal milk fat protein content, which is nearly absent from SMP. Comparative analysis of WPC-C and WPC-L indicated higher levels of threonine, serine, glutamic acid, and proline in WPC-C but lower levels of tyrosine, phenylalanine, and tryptophan, attributed to the different methods of separation from casein proteins. WPI and WPC-HF originate from similar sweet whey streams but follow divergent processing methods; consequent on this were variations in the levels of all AAs except histidine. The nanofiltration step in D90 production retains its non-protein nitrogen content and affects its AA profile; consequently, D90 consistently exhibited lower AA levels than WPC-C. These findings underscore the significant impact of manufacturing processes on dairy powder AA composition. Full article

Sheep’s second cheese whey (SCW), the by-product resulting from whey cheese production, was used as a component of cheese coatings containing oregano (Origanum compactum) and clary sage (Salvia sclarea) essential oils (EOs). SCW powder was obtained by the ultrafiltration/diafiltration of SCW followed by reverse osmosis and freeze drying. The coatings were produced with a mixture of SCW and whey protein isolate (WPI) using glycerol as plasticizer. Model cheeses were produced with cow´s milk and those containing SCW:WPI coatings; those with and without EOs were compared to controls without coating and with a commercial coating containing natamycin. At the end of ripening (28 days), the cheeses containing EOs presented higher water activity (ca. 0.930) and moisture content, as well as lower titratable acidity. Concerning color parameters, significant differences were also observed between products and as a result of ripening time. However, the use of SCW:WPI coatings did not significantly influence the color parameters at the end of ripening. Regarding texture parameters, the cheeses containing SCW:WPI coatings presented significantly lower values for hardness, chewiness, and gumminess. Significant differences were also observed for all microbial groups evaluated either between products and as a result of ripening time. In all cases, lactobacilli and lactococci counts surpassed log 7–8 CFU/g, while the counts of yeasts and molds increased steadily from ca. log 3 to log 6 CFU/g. The lowest counts of yeasts and molds were observed in the samples containing natamycin, but nonsignificant differences between products were observed. In conclusion, SCW:WPI cheese coatings can successfully substitute commercial coatings with the advantage of being edible packaging materials manufactured with by-products. Full article

Dairy proteins are potential and multipurpose ingredients used to prepare various food products. It exhibits many beneficial functionalities and bioactivities in the processing of food products. All the functionalities of different dairy proteins depend on their peculiar structural characteristics. So, the present study aimed to characterize high-protein powders with different matrices (milk protein concentrate (MPC), rennet casein (RCN), micellar casein concentrate (MCC), whey protein isolate (WPI), and native whey concentrate (NWC)) for their composition, handling, and reconstitution properties, and microstructure and compared them with whole milk powder (WMP) and skim milk powder (SMP). The bulk density of the high-protein powders was significantly (p < 0.05) lower than WMP and NFDM. Due to the low bulk density of the high-protein powders, the wettability of these powders in the water was very high. Microstructural analysis of powders by scanning electron microscopy reveals that the high-protein powder had tetrahedron-to-polyhedron-shaped particles depending on the protein level. The idea regarding the powder’s morphology might be helpful for further improvement in the production processes to modify the functional properties of high-protein milk powders. Full article

Fibrinolytic enzymes are a kind of proteolytic enzymes that can hydrolyze fibrin and dissolve blood clots. They could be used as a therapeutic agent for treating thrombosis. It is important for the treatment of cardiovascular disease to find and develop new thrombolytic drugs. In order to explore new fibrinolytic enzymes, a strain named 214L-11 with protease and fibrinolytic enzyme activity, which was isolated from the Flaming Mountain of Xinjiang Province, was screened using the skimmed milk plate, the blood powder agarose plate and the fibrin plate methods. Phylogenetic analyses showed that strain 214L-11 shared the highest similarity with Streptomyces fumanus NBRC 13042T (98.88%), which indicated that it represented a potential novel species in the Streptomyces genus. The fibrinolytic enzyme produced by 214L-11 displayed thrombolytic and anticoagulant activities, and it could degrade a single specific protein in the thrombus, thereby destroying the thrombus structure. The fermentation medium optimized through response surface methodology was 15 g/L soluble starch, g/L KNO₃ 0.58, 0.43 g/L peptone, 0.01 g/L FeSO₄·7H₂O, 0.5 g/L MgSO₄·7H₂O, 0.2 g/L Mn²⁺, 0.5 g/L NaCl and 1 L distilled water, pH 8, and the maximum amount of fibrinolytic enzyme produced by strain 214L-11 in the optimal fermentation medium was 1255.3 FU/mL. Overall, the fibrinolytic enzyme-producing strain was screened from the Flaming Mountain of Xinjiang for the first time, which provided a basis for further research and the development of new efficient and safe hemolytic drugs. Full article

Salmonella is a common foodborne infection. Many serovars belonging to Salmonella enterica subsp. enterica are present in the gut of various animal species. They can cause infection in human infants via breast milk or cross-contamination with powdered milk. In the present study, Salmonella BO was isolated from human milk in accordance with ISO 6579-1:2017 standards and sequenced using whole-genome sequencing (WGS), followed by serosequencing and genotyping. The results also allowed its pathogenicity to be predicted. The WGS results were compared with the bacterial phenotype. The isolated strain was found to be Salmonella enterica subsp. enterica serovar Typhimurium 4:i:1,2_69M (S. Typhimurium 69M); it showed a very close similarity to S. enterica subsp. enterica serovar Typhimurium LT2. Bioinformatics sequence analysis detected eleven SPIs (SPI-1, SPI-2, SPI-3, SPI-4, SPI-5, SPI-9, SPI-12, SPI-13, SPI-14, C63PI, CS54_island). Significant changes in gene sequences were noted, causing frameshift mutations in yeiG, rfbP, fumA, yeaL, ybeU (insertion) and lpfD, avrA, ratB, yacH (deletion). The sequences of several proteins were significantly different from those coded in the reference genome; their three-dimensional structure was predicted and compared with reference proteins. Our findings indicate the presence of a number of antimicrobial resistance genes that do not directly imply an antibiotic resistance phenotype. Full article

Milk protein isolate powder (MPIP), a high protein-based powder, is a common dietary ingredient but has poor physical properties due to its cohesive nature. Powder agglomeration is one of the most widely used methods to improve and modify the quality of MPIP structures. In this study, the physical, morphological, and rheological properties of MPIPs agglomerated in a fluidized-bed agglomeration process were investigated as a function of sugar binder type and concentration. The physical properties of MPIP were evaluated by their flowability, cohesiveness, porosity, particle size distribution (PSD), and water-holding properties (wettability, solubility, and water-binding capacity). The density values of the agglomerated MPIPs decreased with increasing the binder concentration, whereas the porosity, wettability, and solubility values increased. Such trends were consistent with SEM observations. The MPIP agglomerated with 10% sorbitol had the largest particle diameter (D₅₀) and showed better physical properties compared to the other sugar binders. The viscosity values (η_a,50) of the MPIPs agglomerated with sugar binders showed lower values than the control (no sugar binder). The agglomeration process enhanced the viscoelasticity of the MPIP, but the viscoelasticity decreased with increasing the sugar binder concentration. These observations suggested that the physical, morphological, and rheological properties of MPIP can be greatly affected by the binder type and concentration in the agglomeration process. Full article

The use of caseinate, whole milk powder, and two whey protein preparations (WP; 2% w/w) was studied in minced meat made with normal breast (NB), and ones showing spaghetti meat (SM). SM is an emerging myopathy known for muscle fiber separation and lower protein content, costing $100s of millions to the industry. Using SM without dairy proteins resulted in a higher cooking loss (SM: 3.75%, NB: 2.29%; p < 0.05), and lower hardness (SM: 29.83 N, NB: 34.98 N), and chewiness (SM: 1.29, NB: 1.56) compared to NB. Using dairy proteins, except WP concentrate and WP isolate, significantly improved yield and increased hardness. Adding WP isolate to SM resulted in a similar texture profile as NB samples without dairy proteins (34 and 35 N hardness; 0.22 and 0.24 springiness; 1.57 and 1.59 chewiness values, respectively). Adding caseinate and whole milk to SM showed a more substantial effect of improving water-holding capacity, increasing hardness, gumminess, and chewiness compared to adding WP; i.e., adding caseinate and milk powder resulted in higher values for those parameters compared to NB without additives. Overall, it is shown that dairy proteins can be added to SM to produce minced poultry meat products with similar or higher yield and texture profiles compared to using normal breast fillets. Full article

The present study aims to describe colloidal and acid gelling properties of mixed suspensions of pea and milk proteins. Mixed protein suspensions were prepared by adding pea protein isolate to rehydrated skimmed milk (3% w/w protein) to generate four mixed samples at 5, 7, 9, and 11% w/w total protein. Skimmed milk powder was also used to prepare four pure milk samples at the same protein concentrations. The samples were analyzed in regard to their pH, viscosity, color, percentage of sedimentable material, heat and ethanol stabilities, and acid gelling properties. Mixed suspensions were darker and presented higher pH, viscosity, and percentage of sedimentable material than milk samples. Heat and ethanol stabilities were similar for both systems and were reduced as a function of total protein concentration. Small oscillation rheology and induced syneresis data showed that the presence of pea proteins accelerated acid gel formation but weakened the final structure of the gels. In this context, the results found in the present work contributed to a better understanding of mixed dairy/plant protein functionalities and the development of new food products. Full article

The stabilization of probiotics for application in non-refrigerated food products is a challenging task. In the present study, probiotic Lactobacillus paracasei (Lacticaseibacillus paracasei) ATCC 55544 cells were immobilized in a dairy matrix comprising of whole milk powder, skim milk powder, or milk protein isolate using fluidized bed drying technology. The samples were taken out at different drying stages, with an apparent water activity (a_w) of a_w 0.5, a_w 0.4, and a_w 0.3, respectively, and vacuum-packed to maintain the a_w and stored at three different temperatures of 4 °C, 25 °C, and 37 °C. The study evaluated the impact of matrix constituents, milk fat, protein, and carbohydrate on the viability of encapsulated probiotic L . paracasei ATCC 55544 during storage for 1 month. The whole milk powder matrix provided superior protection to the bacteria. Confocal Laser Scanning Microscopy (CLSM) was used to investigate the structure of the immobilizing matrix and the location of the probiotic L. paracasei cells embedded within the matrix. The CLSM study revealed that the probiotic bacterial cells are mostly embedded as clusters beneath the top layer. We hypothesize that the biofilm-like structure, together with the protective whole milk powder matrix, helps to retain the superior viability of probiotic cells during storage at non-refrigerated storage conditions of 25 °C and 37 °C. Full article

The introduction of membrane filtration during infant milk formula (IMF) processing represents an innovative approach to increasing native protein content compared to standard IMF. The objective of this study was to compare IMF powder produced using a standard process and IMF produced from raw bovine skim milk with added whey protein isolate using a split-stream process incorporating a ceramic 1.4 μm filter followed by a polyvinylidene difluoride polymeric 0.2 μm filter. Retentates from 0.2 μm microfiltration (MF) were blended with fat, lactose, and minerals and subsequently high-temperature treated (125 °C × 5 s). The heat-treated retentate was merged with the permeate from the 0.2 μm MF, homogenised, and spray-dried (referred to as membrane-filtered IMF or MEM-IMF). A control IMF was also produced using standard treatment (referred to as high-temperature IMF or HT-IMF) without membrane filtration. Both IMF products were characterised by high-performance liquid chromatography, particle size, and enzyme activity assays. MEM-IMF powder had significantly higher amounts of native (1.1 g per 100 g powder) and monomeric (1.48 g per 100 g powder) whey proteins when compared to 0.18 and 0.46 g per 100 g powder in HT-IMF, respectively. MEM-IMF also exhibited a lower degree of protein aggregation compared to HT-IMF. Comparison of microbial and Maillard by-products markers demonstrated that a safe IMF product could be produced at scale, although levels of the Maillard by-product marker, carboxymethyl-lysine, were not significantly reduced in MEM-IMF. This study demonstrates how membrane filtration can be used to retain native proteins during IMF manufacture. Full article