Milk Protein Hydrolysates Research Articles

Milk-derived bioactive peptides in insulin resistance and type 2 diabetes.

Diabetes is a global health issue affecting over 6% of the world and 11 % of the US population. It is closely linked to insulin resistance, a pivotal factor in Type 2 diabetes development. This review explores a promising avenue for addressing insulin resistance through the lens of Milk-Derived Bioactive Peptides (MBAPs). Taken from casein or whey fractions of various milks, MBAPs exhibit diverse health-promoting properties. Specific interactions between these peptides and enzymes involved in glucose digestion and metabolism have been examined, leading to the identification of some key peptides exerting the effects. This review emphasizes the positive impact of MBAPs on glycemic control through various mechanisms. Different cell lines have been used to investigate MBAPs' effects on insulin signaling, inflammation, and oxidative stress. Preclinical in vivo studies have also shown that MBAPs lower glucose, stimulate insulin, and reduce inflammation. Human trials further substantiate these findings and suggest the potential utility of milk protein hydrolysates containing MBAPs in individuals with insulin resistance or T2D to improve insulin action and glucose homeostasis.

Stabilization of Zinc Ions and Potassium Phosphates Using Milk Protein Hydrolysates and In-Vitro Evaluation of Dentinal Tubule Occlusion

Stabilization of Zinc Ions and Potassium Phosphates Using Milk Protein Hydrolysates and In-Vitro Evaluation of Dentinal Tubule Occlusion

Mechanisms of reduced sensitization by extensive hydrolysis of milk protein concentrate: Impact on the immune response of Th1/Th2 and Treg/Th17 cells in mice.

Extensively hydrolyzed protein products not only provide sufficient nutrition but also effectively reduce the allergenicity of milk proteins. However, there was limited information about the sensitization of extensive hydrolysate of milk protein concentrate (EMPHs). In this study, the mechanism by which EMPHs reduce sensitization was studied by constructing an milk protein concentrate (MPC) sensitization evaluation animal model. The results demonstrated that the serum levels of the specific IgE, IgG and IgG1 antibodies in the EMPH group (O-AX and T-AX) were significantly decreased (P < 0.01). In addition, compared with the MPC group (19.29%), the expression of CD3+CD4+ T cells in the O-AX (16.61%) and T-AX groups (15.94%) was significantly reduced (P < 0.05). This indicated an imbalance of Th1/Th2 in the MPC group, which was confirmed by the results of cytokines and transcription factors in the spleen. The mice in the control MPC group highly expressed FcεRI+CD117+ mast cells (22.25%), peripheral blood B cells (2.91%) and CD3+CD8+ T cells (8.65%). The results indicated that EMPHs did not cause an imbalance of Th1/Th2 cells and Treg/Th17 cells in mice and had lower sensitization.

Exploring the Functional Potential of Breast Milk Protein Hydrolysates: Antiglycation, Antioxidant, Metal Chelation, and Lipid Peroxidation Activities

The formation of advanced glycation end products (AGEs) is a pivotal factor in the development of various age-related and diabetes associated pathophysiologies, including but not limeted to arthritis, Alzheimer’s disease, atherosclerosis and cataracts. Consequently, the prospect of inhibiting AGE formation emerges as a viable strategy to prevent or halt the advancement of diabetic complications. In the scientific literature, there is still a reluctance to produce bioactive peptides demonstrating antiglycation activity from breast milk. The breast milk protein was hydrolysed using trypsin for 240 min. The antiglycation, metal chelating activity, lipid peroxidation activity, and antioxidant activity of the peptides in the hydrolysates obtained after hydrolysis of human milk with trypsin enzyme were performed. The peptide diversity obtained after hydrolysis was determined by RP-HPLC. The breast milk hydrolysate was demonstrated significant antiglycation activity (IC50: 312.8 ± 12.1 µg/mL), antioxidant activity (61.8±4.58 mM AAE/µg peptide) , metal chelation activity (24.4%/μg peptide). The hydrolysate effectively inhibited lipid peroxidation (30.5±0.12%) compared to Trolox (51.2±0.3%). These findings highlight the potential of breast milk protein hydrolysates as a source of bioactive peptides with diverse health benefits. The present study offers valuable insights into utilizing human milk peptides as novel functional food components.

Sensory evaluation of pea and milk protein hydrolysates used to develop protein-fortified tomato soup

Protein is a required macronutrient for maintenance of muscle mass. Current guidelines recommend daily intake of 0.8 g of dietary protein per kilogram body weight (kg bw), regardless of age(1). However, factors such as age and physiological changes may increase this requirement to 1.5g/ kg bw/day for older adults with sarcopenia(2). Therefore, protein-fortified foods are used to enhance the protein intake of older adults. Milk protein concentrate (MPC) and pea protein isolate (PPI) ingredients are used to increase the protein content of different foods(3–6). However, their addition changes the functional and sensory properties of the final protein-fortified product(7). Therefore, enzymatic hydrolysis is employed to improve the techno-functional properties of these ingredients, however, the bitterness of the resulting hydrolysates limits their application. This study aimed to investigate the effect of hydrolytic enzyme preparation on the taste properties of MPC and PPI hydrolysates when incorporated as ingredients in protein-fortified tomato soup.Solutions of MPC and PPI containing 3% total solids (w/w) were hydrolyzed at 50°C for 30 min using Neutrase®, Umamizyme and Protease AN “Amano” 100SD at an enzyme-to-substrate ratio of 1%. Bitterness in the hydrolysates was assessed with 16 semi-trained participants using labeled magnitude scales (LMS) and by 44 participants using a ranking test. Both tests showed that the least bitter hydrolysates were those generated using Umamizyme and Protease AN “Amano” 100SD. These hydrolysates were used to develop protein-fortified tomato soup with 3% of protein powders, that were characterised by 38 naïve consumers using hybrid quantitative descriptive profiling.ANOVA on the bitter taste revealed that soups containing hydrolysed MPC (regardless of the hydrolytic enzyme used) were significantly more bitter compared to the control unhydrolyzed protein-fortified tomato soup (p&lt;0.001). Bitterness in the protein-fortified tomato soup was masked using various ingredients, applying the principle of taste-taste interactions. A ranking test with 43 naïve participants showed that a combination of tomato puree and sucrose successfully reduced bitterness.Overall, the enzyme preparation used affected the bitterness of the MPC and PPI hydrolysates and consequently the taste of the protein-fortified tomato soup. The use of Umamizyme and Protease AN Amano resulted in less bitter protein hydrolysates (both PPI and MPC) compared to Neutrase (p&lt;0.001). Taste-taste interactions resulting from a combination of ingredients could successfully be employed to reduce bitterness in the protein-fortified tomato soup. Since these soups are aimed to be consumed by older people, further work will aim to test their preference.

An examination of factors that influence infant growth in the first weeks of life

Childhood obesity is a serious public health concern worldwide. One in five children are overweight or obese in Ireland1. Suboptimal growth, either in pregnancy or infancy, can increase the risk of obesity in childhood2. National policy fails to recognise early life exposures as potential contributors to Ireland’s obesity epidemic. This research examines the impact of ‘Labour and Birth’, ‘Birth Weight Status’, and ‘Maternal BMI’ on infant growth in the first weeks of life.This research is a secondary analysis of data collected as part of the WellFed study, a randomised placebo-controlled trial investigating the effect of a maternal dietary supplement comprised of a milk protein hydrolysate and yeast beta-glucan (Wellmune®) (LS-23-07-OSullivan). The supplement does not influence the present findings. Mother and infant anthropometrics were measured during two study visits, at approximately 4 and 8-weeks postpartum. Participants completed a series of questionnaires to obtain basic demographic, birth and lifestyle data. Infant weight and length percentiles were calculated using the UK-WHO 0-2 years: weight-for-age percentiles and the UK-WHO 0-2 Years: length-for-age percentiles for both males and females. Statistical analysis was performed using IBM SPSS Statistics (version 27).Data from 51 mother-infant dyads show infants delivered via cesarean section weighed less at the 4-week (4.1 ± 0.4 vs 4.5 ± 0.5 kg, p = 0.015) and 8-week follow-up (5.1 ± 0.5 vs 5.5 ± 0.6 kg, p = 0.021) and were shorter at the 8-week follow-up (56.3 ± 1.9 vs 57.7 ± 2.0 cm, p = 0.030) compared to infants born vaginally. Infants born following induction were significantly heavier at the 8-week follow-up compared to those not-induced (5.8 ± 0.7 vs 5.2 ± 0.5 kg, p = 0.006). In this cohort, 40% of infants were classified as large-for-gestational-age (LGA). Across the 8-week study period, 50% of LGA infants dropped two or more growth percentiles.Observations from this study highlight a high prevalence of LGA infants in this cohort which raises concern for the national prevalence of LGA infants in Ireland. Interventions during labour and birth were shown to influence infant growth in this study. These findings highlight the need for further investigation into the relationship between early life exposures and growth during infancy and childhood. Implementing healthcare policies focusing on reducing the number of elective birthing procedures performed and targeting obesity amongst women of reproductive age are possible measures that can be implemented to help tackle the obesity crisis in Ireland.

Influence of enzymatic hydrolysis conditions on antimicrobial activities and peptide profiles of milk protein-derived hydrolysates from white wastewater

The focus of our investigation lies in the hydrolysis of milk proteins found in the substantial wastewater generated by the dairy industry, particularly in the white and cleaning wastewater resulting from rinsing and cleaning-in-place processes in order to enhance the value of dairy constituents by producing a diverse population of peptides, including potential antimicrobial peptides generated by 4 different enzymes: pepsin, trypsin, pronase E, and thermolysin. The protein/peptide content was influenced by the degree of hydrolysis values ranging from 2 % to 13 %, and UPLC-MS/MS characterization reveals distinct peptide sequences in enzymatic hydrolysates. The impact of hydrolysis time was also examined, revealing significant differences between 30 minutes and 240 minutes, with 555 peptides identified at 30 minutes, increasing to 693 at 240 minutes. After 4 hours, grouping showed variations: 181 peptides (thermolysin), 153 (pepsin), 126 (trypsin), and 83 (pronase E). A comparative analysis of the characterized sequences with antimicrobial peptides databases identified 17 antimicrobial peptides after 240 minutes pronase E and thermolysin hydrolysis, though they were insufficient to inhibit strains like Clostridium tyrobutyricum and Pseudomonas aeruginosa. Antimicrobial assays also revealed that peptides from Pronase T30, Pronase T240, and Thermolysine T240 exhibited antifungal activity against Mucor racemosus (MIC 2.5 mg/mL), but none against Penicillium commune. The effet of enzymatic hydrolysis demonstrated in this study highlights, for the first time, the potential for valorizing dairy white wastewater within the context of a circular economy framework.

The quality and flavor profile of fermented milk produced by Streptococcus thermophilus ABT-T is influenced by the pfs gene in the quorum sensing system

The luxS/AI-2 quorum sensing (QS) system of Streptococcus thermophilus regulates strain acid tolerance, yet its impact on milk fermentation remains unclear. This study aimed to elucidate the mechanism of luxS and pfs gene overexpression in the luxS/AI-2 system of S. thermophilus ABT-T on fermented milk quality using metabolomics. Results showed that pfs gene overexpression had a greater impact on milk quality than the wild-type strain or luxS gene overexpression strain. Overexpression of the pfs gene significantly enhanced AI-2 secretion, reducing fermented milk pH, increasing acidity, improving fermented milk protein hydrolysis, and altering texture and water-holding capacity. Nineteen volatile flavor compounds were identified, with decreased ketone compounds due to the pfs gene overexpression. KEGG analysis suggested significant alterations in amino acid metabolism pathways due to the pfs gene overexpression. This study provides insights into the role of QS in fermented foods.

Flaxseed Oil, Casitose, and Its Combination Diets Increase Antioxidant Activity and Upregulates Aging-related Genes in Drosophila melanogaster

Abstract Background: Nutrigenomics refers to the study of how diet influences the genomic expression and function of an organism. Diet is a significant factor that impacts metabolism, aging, and lifespan. Long-term dietary patterns can influence the risk of age-related diseases, including diabetes, cardiovascular diseases, hypertension, and cancer. While research in Drosophila melanogaster has focused on areas such as calorie restriction, high-sugar and high-fat diets, micronutrients, and disease-specific nutritional interventions, the effects of different combinations of macronutrients have not been adequately studied. This study aimed to analyze the impact of individual macronutrients, specifically flaxseed oil (a source of fat) and casitose (hydrolyzed milk protein), as well as their combinations, on longevity, antioxidant activity, and the expression of aging-related genes in D. melanogaster. Methods: The study examined the in vivo effects of different concentrations of flaxseed oil (120 μl, 240 μl, 480 μl, and 960 μl), casitose (125 mg, 250 mg, 500 mg, and 1000 mg), and their combinations with a base diet on longevity, antioxidant activity, and the expression of aging-related genes, namely manganese superoxide dismutase (Mn-SOD or SOD1) and copper–zinc SOD (Cu-Zn SOD or SOD2) in D. melanogaster. Results: The study found that flaxseed oil, casitose, and their combinations increased lipid peroxidation (LPO) activity, leading to the production of reactive oxygen species. However, these substances also enhanced the activity of the antioxidant enzymes SOD and catalase, which help combat-free radicals. Furthermore, the gene expression of SOD1 and SOD2 was upregulated, suggesting a potential mechanism for the observed improvements in lifespan. Interestingly, high doses of flaxseed oil (960 μl) were associated with decreased lifespan in the flies. Conclusion: The findings indicate that the optimal levels of flaxseed oil, casitose, or their combination can increase lifespan in Drosophila by upregulating the expression of the antioxidant enzymes SOD1 and SOD2. This provides insights into the potential of targeted nutrient combinations as a dietary approach to combat aging-related diseases.

Characterization and evaluation of the in vitro and in vivo anti-diabetic activities of camel milk protein hydrolysates derived with different protease digestions

The study aimed to determine the potential anti-diabetic activities of the hydrolysates of camel milk proteins (CMPH). Camel milk proteins were hydrolyzed independently by using 11 proteases, and their anti-diabetic activities were analyzed by in vitro, and in vivo. The results showed that CMPH-Flavourzyme exhibited the best α-glucosidase and dipeptidyl peptidase-IV inhibitory activity, while CMPH-Papain exhibited the highest α-amylase inhibitory activity, and best proliferative effect on streptozotocin-induced NIT-1 cells in vitro. Furthermore, CMPH-Papain exhibited the most effect in decreasing the serum levels of fasting blood glucose, oral glucose tolerance test, pro-inflammatory factors (IL-1β, IL-6) and triglyceride, as well as increasing insulin levels on in vivo streptozotocin-induced diabetic mice. Peptides identification followed with molecular docking and network pharmacology analysis also found the potential anti-diabetic peptides from CMPH-Flavourzyme and CMPH-Papain. Our results indicated the type of protease used for the treatment significantly influences the anti-diabetic activities of the resulting CMPH.

Enzymatic Modification of Cow, Buffalo and Goat Milk Proteins and their Effect on Anti-Oxidant Activity and Digestibility

Aim: Buffalo milk and goat milk were enzymatically hydrolyzed to have 5, 10 and 15 per cent DH to improve the techno-functional properties of milk proteins in order to utilize in production of channa based dairy products. Study Design: A significant contribution to total milk production of India comes from buffalo milk and followed by cow and goat milk. Inspite of that, Buffalo milk and goat milk are not being utilized for many products in view of their inherent problems associated in production of Chhana based dairy products. Buffalo milk and goat milk were enzymatically hydrolyzed to have 5, 10 and 15 per cent DH to improve the techno-functional properties of milk proteins in order to utilize in production of products. Place and Duration of Study: Karnataka Veterinary Animal and Fisheries Sciences University (KVAFSU), Dairy Science College, Hebbal, Bangalore Karnataka, India Methodology: The Goat milk samples were collected from Sinchana Goat and sheep farm, Marenahalli village (Bengaluru Rural Dist) and Buffalo milk was obtained from country Delight Pvt. Ltd., J. P. Nagar, Bengaluru, Karnataka. Cow milk used in this investigation was collected from SEDP, Dairy Science College, Hebbal, Bangalore. Commercially available pure Neutrase enzyme was purchased from DSM Nutritional Products India Pvt. Ltd, Bangalore. All the glassware used were soaked in chromic acid solution, repeatedly washed with water, rinsed with distilled water and dried before use. For microbiological analysis dried test tubes, conical flask, pipettes were cotton plugged and sterilized in hot air oven. The chemicals and reagents used in this study were mainly of analytical grade procured from Prince Laboratory Company Pvt limited, Bangalore. The protein molecular weight markers were used for the electrophoretic study were procured from Bangalore Genei Pvt Ltd. Results: Highest protein content was noted in buffalo casein hydrolysate (83.0 %) than cow (81.0 %) and goat (81.16 %) and lowest nitrogen and ash content was observed in goat casein hydrolysate (13.65 %) and (15.20 %) respectively. (Akshya pl include few lines of enzymatic modification on anti-oxidant property and digestibility copy from discussions) Conclusion: Though buffalo milk contributes nearly half of the total milk production of India and goat milk carries both nutritional and therapeutic benefits, the potential utilization of both these milks are very much limited due to the inherent problems associated with them. This investigation has shown that by enzymatically hydrolyzing buffalo milk and goat milk to 5 per cent DH results significant improvement in physico-chemical and functional attributes Rasagulla which is on par with cow’s milk protein hydrolysates. Recommendation: Scavenging activity or anti-oxidant activity and Digestibility of hydrolysates has been studied as influenced by the extent of enzymatic modification in this study.

Lacticaseibacillus paracasei JY025 fortified milk powder: In vitro digestion characteristics and accelerated storage stability

To clarify the reciprocal influence between the fortified bacterial powder of Lacticaseibacillus paracasei JY025 (LBP) with milk powder matrix during the gastrointestinal digestion and storage period, the digestion characteristics and storage stability of Lacticaseibacillus paracasei JY025 fortified milk powder (LFMP) were explored in this study by the in vitro simulated digestion and the accelerated storage. The results showed that the milk powder matrix significantly improved the survival of JY025 during the simulated digestion (the highest improvement of 27%) and storage period (the highest improvement of 37%), which suggests the milk powder matrix can be an effective strategy to enhance the viability of probiotics during the digestion and storage period. Moreover, the digestion characteristics and the physicochemical properties of the milk powder matrix were changed due to the fortified LBP during the simulated digestion and storage period. The fortified LBP decreased the particle size of milk powder digest and promoted the hydrolysis of milk protein during digestion due to the effect of both maltodextrin (wall material) and bacteria. The fortified LBP also increased the particle size of milk powder matrix and decreased the Maillard reaction of milk powder matrix during the storage period, which is closely related to the storage condition.

Improved Bacterial Survival and Antioxidant Activity After In Vitro Digestion of Fermented Dairy Beverages by Lacticaseibacillus casei LC-01 and Lactiplantibacillus plantarum BG-112 Containing Yacon.

The fermentation of milk containing 0%, 3%, 6%, and 9% (w/v) yacon root flour (YRF) by Lacticaseibacillus casei LC-1 and Lactiplantibacillus plantarum BG-112 was evaluated for bacterial survival and antioxidant activity (AA) before and after simulated gastrointestinal digestion. After 28days of refrigerated storage, samples of the beverages were analyzed for cell viability, AA (using ferric ion reducing antioxidant power (FRAP) and (ABTS), and molecular mass profile of proteins (using electrophoresis). The presence of 9% YRF increased bacterial survival during 28days of storage and passage through the gastrointestinal tract for both L. casei and L. plantarum, which showed a greater capacity to reduce ferric ions compared to 0% YRF, and the ability to capture free radicals increased from below 5mM to over 15mM TE after digestion. Milk proteins are hydrolyzed during digestion, and the generation of bioactive peptides with AA may explain the increase in AA levels. Since peptides are generated from milk proteins, YRF did not influence AA after digestion. These results showed that fermentation of milk by L. casei and L. plantarum with YRF increased the chances of these bacteria reaching the colon in adequate quantities. After simulated digestion, the beverages showed improved AA due to milk protein hydrolysis.

Identification and molecular docking of a novel antidiabetic peptide from protamex-camel milk protein hydrolysates against α-amylase and DPP-IV

Antidiabetic peptides were identified from camel milk protein hydrolysates, and their inhibitory activities against α-amylase and dipeptidyl peptidase-IV (DPP-IV) were determined. The possible binding mechanism between the enzymes and the peptide was elucidated through molecular docking. Camel milk proteins were hydrolyzed using protamex, and the hydrolysates were divided into three fractions (>10, 3–10, and <3 kDa) through ultrafiltration. Fraction <3 kDa was more effective at inhibiting α-amylase and DPP-IV and was purified through gel chromatography and identified through LC-MS/MS. In total, 20 peptides were considered as potential bioactive peptides, mainly derived from β-casein. The novel peptide QEPVPDPVRGL exhibited the most potent antidiabetic activity and spontaneously interacted with α-amylase and DPP-IV through hydrogen bonds, salt bridges, and pi–alkyl, thereby occupying their active cavities. This study indicated that camel milk protein hydrolysates are good sources of peptides with antidiabetic potential.

Influence of lactoferrin and enzymatiс hydrolysates of cow's and mare's milk proteins on anaphylactic sensitivity and cytokine profile of rats

The development of innovative ingredients of specialized formula for children with intolerance to cow's milk proteins requires accounting the influence of the protein component on the allergic sensitivity. The aim of the research was to study the effect of lactoferrin (LF) from cow colostrum, cow's milk protein hydrolysate (CMPH) and mare's milk protein hydrolysate (MMPH) on the severity of the systemic anaphylaxis reaction, the levels of specific IgG antibodies and cytokines in rats parenterally sensitized with ovalbumin (OVA). Material and methods. The experiment was carried out on 4 groups of 26 male Wistar rats, which were sensitized intraperitoneally with chicken egg OVA and a systemic anaphylaxis reaction was induced on the day 29 by intravenous administration of a challenge dose of the antigen (6 mg per kg body weight). LF, CMPH and MMPH were introduced into the diet in doses of 1.4-2 g/kg body weight per day (on an average 1.59±0.04, 1.53±0.05 and 1.48±0.05 g per kg body weight respectively). The content of IgG antibodies in the blood serum was determined by an indirect ELISA; the levels of cytokines IL-1α, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12(p70), IL-13, GM-CSF, IFN-γ and TNF-α were detected by multiplex immunoassay. Results. Dietary LF did not have a significant effect on the severity of active anaphylactic shock (AAS), concentrations of antibodies and cytokines in the blood of animals. As a result of CMPH consumption, there were no significant changes in AAS severity and IgG antibodies to OVA but significant increase in TNF-α level was observed as well as a significant decrease in IL-1α (p<0.05). In animals receiving MMPH, there were also no significant changes in the severity of AAS, but a 1.9-fold decrease in the level of IgG antibodies to OVA (p<0.001) was noticed along with a significant increase in IL-12(p70) (p<0.05) and IL-10 (p<0.10) level. Conclusion. Cosumption of LF by sensitized rats didn't significantly affect their anaphylactic sensitivity and cytokine profile, while CMPH intake induced some signs of pro-inflammatory processes. Consumption of MMPH was accompanied by the formation of an anti-inflammatory cytokine profile, which corresponds to a decrease in the intensity of the humoral immune response to the model allergen. Differences in the effects of two hydrolisates, which have similar degrees of hydrolysis, may be associated with the specific composition of glycopeptides formed during the enzymatic cleavage of milk protein produced by these two species of dairy animals.

Enzymatic debittering of cheese flavoring and bitterness characterization of peptide mixture using sensory and peptidomics approach

Peptides in cheese flavoring produced through proteolysis plus fermentation generated bitterness. Bitterness of individual peptide can be quantified using quantitative structure–activity relationship, where molecular mass (M), hydrophobicity, residues, C-terminal hydrophobic amino acids (C-HAAs), and N-terminal basic ones (N-BAAs) are crucial. However, their accumulative influence on the overall bitterness of peptide mixture remains unknown. This study delved into extensive proteolysis to debitter and to correlate the multi-influencing factors of peptides and the collective bitterness. As hydrolysis increased from 7.5 % to 28.0 %, bitterness reduced from 5.0 to 0.3–2.7 scores, contingent on proteases used, in which FU was optimal. The overall bitterness cannot be predicted through the summation of individual peptide bitterness, which depended on M (0.5–3 kDa) and 5–23 residues, followed by N-BAAs and C-HAAs. Analysis of enzymatic cleavage sites and substrate characteristics revealed, to more effectively debitter bovine milk protein hydrolysates, proteases specifically cleaving Pro, Leu, Phe, and Val were desired.

Enzymatic hydrolysis and extensive heat treatment induce distinct modifications of cow's and camel milk proteins of relevance for production of infant formula

Camel milk is an alternative to cow's milk as protein source for infant formula. Reduced allergenicity is usually obtained through enzymatic hydrolysis of milk proteins. Heat treatment is another route to modify allergenicity. This study investigated the effect of enzyme hydrolysis and extensive heat treatment on the size, aggregation mechanisms, and modifications of camel milk proteins in comparison to the effect on cow's milk proteins. Disulphide bonds stabilized casein micelles in cow's milk but not in camel milk. The formation of large stable complexes by extensive heat treatment was prominent in cow's milk and not in camel milk. In both milks heat treatment led to equal levels of Maillard reaction, whereas sugar independent cross-linking was less pronounced in camel milk. Low sequence identity, different relative composition, and complete absence of β-lactoglobulin in camel milk are likely explanations for the different properties of cow's and camel milk. Production of infant formula based on camel milk should accordingly employ process parameters specifically adapted to this type of milk.

Development of a “Green” Emulsion with a Milk Protein Hydrolysate: An Evaluation of Rheology, Texture, In Vitro Bioactivity, and Safety

Bioactive peptides are promising cosmetic active ingredients that can improve skin health and appearance. They exhibit a broad spectrum of activity, including anti-aging, antioxidant, antimicrobial, and anti-inflammatory effects. The aim of this study was to develop a safe, stable, and efficacious environmentally friendly (“green”) emulsion using a milk protein hydrolysate as a model active ingredient. Potential emulsions were formulated with biodegradable emollients, stabilized with naturally derived mixed emulsifier, and prepared by cold process. They were evaluated for rheological behavior (continuous rotation and oscillation tests), physical stability (dynamic mechanical thermal analysis—DMTA test), and texture profiles, as well as cytotoxic, antioxidant, and antimicrobial effects. Rheological characterization revealed shear-thinning flow behavior with yield point from continuous rotation tests and predominantly elastic character from oscillation (amplitude and frequency sweep) tests, with small structural change detected in the DMTA test. These results implied satisfactory rheological properties and good stability. Texture analysis revealed acceptable spreadability and substantivity of the emulsions. The protein hydrolysate showed antioxidant activity. The developed emulsions showed low antibacterial activity against selected microorganisms, but this was due to the action of preservatives, not peptides. All potential emulsions showed a desirable safety profile. The results obtained provide the basis for the next stage of formulation development, i.e., in vivo efficacy tests.

Milk Protein Hydrolysis by Actinidin-Kinetic and Thermodynamic Characterisation and Comparison to Bromelain and Papain.

Plant proteases, including actinidin, papain and bromelain, have been widely used in the food industry but with limited application in dairy systems. This research aimed to establish and compare operational parameters (kinetics, temperature, enzyme type, time and thermodynamics) relevant to the applications of these enzymes in the hydrolysis of whey protein isolates (WPI), whey protein concentrates (WPC) or milk protein concentrates (MPC). The degree of hydrolysis (DH) increased with the rise in temperature, and the maximum DH was achieved at 60 °C for all three dairy systems. The addition of papain resulted in a greater %DH of whey proteins in comparison to bromelain. The cleavage of proteins was clearly time-dependent (p < 0.05), while the pH did not change significantly (p > 0.05) during this time. PAGE analysis revealed that all three enzymes mainly acted on α-lactalbumin and αs-casein in WPI and MPC, respectively. Kinetic parameters from the Lineweaver-Burk plot at 60 °C using WPC and MPC as a substrate varied widely, establishing that WPC hydrolysis was characterised by a lower KM, higher kcat, kcat/KM and Vmax compared to MPC in the case of all three enzymes. The difference in kcat/KM values amongst all enzymes (actinidin > papain > bromelain) indicated the difference in the strength of substrate binding sites. The thermodynamic parameters of these enzymes with MPC and WPC were also determined at a temperature range of 15-60 °C, and the results indicate the potential application of papain and actinidin in the dairy industry.

Safety evaluation of the food enzyme subtilisin from the non-genetically modified Bacillus licheniformis strain NZYM-CX.

The food enzyme subtilisin (EC 3.4.21.62) is produced with the non-genetically modified Bacillus licheniformis strain NZYM-CX by Novozymes A/S. The production strain met the requirements for the qualified presumption of safety (QPS) approach. The food enzyme is intended to be used in eight food manufacturing processes: processing of cereals and other grains for the production of brewed products; processing of dairy products for the production of modified milk proteins and flavouring preparations; processing of plant- and fungal-derived products for the production of plant-based analogues of milk and milk products, protein hydrolysates and edible oils from algae; processing of meat and fish products for the production of protein hydrolysates; processing of yeast and yeast products. Since residual amounts of total organic solids (TOS) are removed in the production of edible oils from algae, dietary exposure was calculated only for the remaining seven food manufacturing processes. Exposure was estimated to be up to 2.393 mg TOS/kg body weight (bw) per day in European populations. As the production strain qualified for the QPS approach and no issues of concern arose from the production process of the food enzyme, the Panel considered that toxicological studies were unnecessary. A search for the similarity of the amino acid sequence of the food enzyme to known allergens was performed, and a total of 20 matches were found, 17 to respiratory allergens, two to food allergens (found in muskmelon and pomegranate) and one to a contact allergen. The Panel considered that the risk of allergic reactions upon dietary exposure to this food enzyme cannot be excluded, especially in individuals sensitised to muskmelon or pomegranate, but would not exceed the risk of consuming these foods. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.