Whey Fraction Research Articles

Peptide YY mediates the satiety effects of diets enriched with whey protein fractions in male rats.

Dairy proteins-whey protein, in particular-are satiating and often recommended for weight control; however, little is known about the mechanisms by which whey protein and its components promote satiety and weight loss. We used diet-induced obese rats to determine whether the hypophagic effects of diets that are enriched with whey and its fractions, lactalbumin and lactoferrin, are mediated by the gut hormone, peptide YY (PYY). We demonstrate that high protein diets that contain whey, lactalbumin, and lactoferrin decreased food intake and body weight with a concurrent increase in PYY mRNA abundance in the colon and/or plasma PYY concentrations. Of importance, blockade of PYY neuropeptide Y receptor subtype 2 (Y2) receptors with a peripherally restricted antagonist attenuated the hypophagic effects of diets that are enriched with whey protein fractions. Diets that are enriched with whey fractions were less preferred; however, in a modified conditioned taste preference test, PYY Y2 receptor blockade induced hyperphagia of a lactoferrin diet, but caused a reduction in preference for Y2 antagonist-paired flavor, which suggested that PYY signaling is important for lactoferrin-induced satiety, but not essential for preference for lactoferrin-enriched diets. Taken together, these data provide evidence that the satiety of diets that are enriched with whey protein components is mediated, in part, via enhanced PYY secretion and action in obese male rats.-Zapata, R. C., Singh, A., Chelikani, P. K. Peptide YY mediates the satiety effects of diets enriched with whey protein fractions in male rats.

Use of whey peptide fraction in coated cashew nut as functional ingredient and salt replacer

Consumers are increasingly concerned about healthy eating habits. The incorporation and stability of 2% antihypertensive whey peptide extract in a new coating of cashew nuts with reduced salt (less 15 and 30%) was studied. The evaluation of nutritional value, in vitro antihypertensive activity and consumer acceptance of final products was assessed. Incorporation of peptide fraction assured the production of a snack with an ACE-inhibitory activity (532.2 μg mL−1 IC50 value). The amount of lipids present in coated cashew nuts was composed mainly by essential fatty acids, mostly monounsaturated. Glutamic acid, leucine, arginine and aspartic acid were the most abundant essential aminoacids. 70% of the consumers considered both samples (15 and 30%) as “ideal taste”. The results suggest that the new coating allowed the development of a new snack with reduced salt content, opening new opportunities as carrier of other ingredients to develop more diversified and efficient functional foods.

Clinical Research and Therapeutic Importance of Dietary Supplement L-Carnitine: Review

Carnitine, derived from an amino acid, is found in nearly all cells of the body. Its name is derived from the Latin carnus or flesh, as the compound was isolated from meat. Carnitine is the generic term for a number of compounds that include L-carnitine, acetyl-L-carnitine, and propionyl-L-carnitine. Carnitine plays a critical role in energy production. It transports long-chain fatty acids into the mitochondria so they can be oxidized to produce energy. It also transports the toxic compounds generated out of this cellular organelle to prevent their accumulation. Given these key functions, carnitine is concentrated in tissues like skeletal and cardiac muscle that utilize fatty acids as a dietary fuel. The body makes sufficient carnitine to meet the needs of most people. For genetic or medical reasons, some individuals (such as preterm infants), cannot make enough, so for them carnitine is a conditionally essential nutrient. Animal products like meat, fish, poultry, and milk are the best sources. In general, the redder the meat, the higher its carnitine content. Dairy products contain carnitine primarily in the whey fraction. Adults eating mixed diets that include red meat and other animal products obtain about 60–180 milligrams of carnitine per day. Vegans get considerably less (about 10–12 milligrams) since they avoid animal derived foods. Most (54–86%) dietary carnitine is absorbed in the small intestine and enters the bloodstream. L-carnitin proved its medicinal importance but in the present era it is neglected. In this review I am trying to explain therapeutic importance of L-carnitin.

Distribution of Spiked Drugs between Milk Fat, Skim Milk, Whey, Curd, and Milk Protein Fractions: Expansion of Partitioning Models.

The distributions of eight drugs (acetaminophen, acetylsalicylic acid/salicylic acid, ciprofloxacin, clarithromycin, flunixin, phenylbutazone, praziquantel, and thiamphenicol) were determined in milk products (skim milk, milk fat, curd, whey, and whey protein) and used to expand a previous model (from 7 drugs to 15 drugs) for predicting drug distribution. Phenylbutazone and praziquantel were found to distribute with the lipid and curd phases (≥50%). Flunixin distribution was lower but similar in direction (12% in milk fat, 39% in curd). Acetaminophen, ciprofloxacin, and praziquantel preferentially associated with casein proteins, whereas thiamphenicol and clarithromycin associated preferentially to whey proteins. Regression analyses for log [milk fat]/[skim milk] and log [curd]/[whey] had r2 values of 0.63 and 0.67, respectively, with p of <0.001 for 15 drugs (7 previously tested and 8 currently tested). The robustness of the distribution model was enhanced by doubling the number of drugs originally tested.

Acidogenic fermentation of the organic fraction of municipal solid waste and cheese whey for bio-plastic precursors recovery – Effects of process conditions during batch tests

The problem of fossil fuels dependency is being addressed through sustainable bio-fuels and bio-products production worldwide. At the base of this bio-based economy there is the efficient use of biomass as non-virgin feedstock. Through acidogenic fermentation, organic waste can be valorised in order to obtain several precursors to be used for bio-plastic production. Some investigations have been done but there is still a lack of knowledge that must be filled before moving to effective full scale plants.Acidogenic fermentation batch tests were performed using food waste (FW) and cheese whey (CW) as substrates. Effects of nine different combinations of substrate to inoculum (S/I) ratio (2, 4, and 6) and initial pH (5, 7, and 9) were investigated for metabolites (acetate, butyrate, propionate, valerate, lactate, and ethanol) productions.Results showed that the most abundant metabolites deriving from FW fermentation were butyrate and acetate, mainly influenced by the S/I ratio (acetate and butyrate maximum productions of 21.4 and 34.5g/L, respectively, at S/I=6). Instead, when dealing with CW, lactate was the dominant metabolite significantly correlated with pH (lactate maximum production of 15.7g/L at pH = 9).

Redox properties of transitional milk from mothers of preterm infants.

There is a discrepancy between the amount of transitional milk produced by mothers of preterm infants and the low capacity of premature infants to consume it. This milk can be used in milk banks, but previous studies found that there are large variations in the level of host-defence proteins in individual samples of milk from mothers of premature infants, which implies that large individual variations in antioxidative defence composition are also possible. Milk samples were collected from 20 healthy mothers of preterm infants. We determined the values for non-enzymatic antioxidative capacity parameters (oxygen radical absorbance capacity (ORAC)), static oxidation-reduction potential (ORP), activities of antioxidant defence enzymes and the amount of vitamin C in whole milk, skim and whey fractions of transitional milk. The main low-molecular-weight antioxidant in transitional milk is vitamin C and most of it is contained in whey. ORAC is higher in whole transitional milk than in skim milk and whey, and ORP is lower in whole transitional milk than that in skim milk and whey. Antioxidative enzyme activities are similar in all individual samples of transitional milk from mothers of preterm infants. Our results indicate that transitional milk of mothers of preterm infants shows slow individual variations in antioxidative defence composition; therefore, it can be used in human milk banks.

Sweet whey as a raw material for the dietary supplements obtaining with immunomodulatory effect

This article presents the results of the study of literary sources to prove the viability of the idea of using sweet whey to deep its fractionation, and to obtain biologically active proteins with immunomodulatory effect. We demonstrated methods for fractionation of milk whey (membrane and chromatographic), as well as the technological scheme of concentration of sweet whey. We introduced the composition of sweet whey and protein content of immunomodulatory action. Modern methods of processing whey, which include, basically, only the process of dehydration and concentration of whey and its use in the complete component composition, which limits its use for food purposes are shown. The necessity of processing of secondary resources in a catastrophic ecological situation on the planet and full use of the composite processing of raw materials for food purposes, and also shows properties of proteins immunomodulating actions which are part of the whey are grounded.

Detection of Mycobacterium avium subspecies paratuberculosis in powdered infant formula using IS900 quantitative PCR and liquid culture media

Mycobacterium avium subspecies paratuberculosis (MAP) has been implicated in Crohn's disease in humans resulting in public concern over the presence of MAP in powdered infant formula, which could contribute towards early human exposure to MAP or MAP components. Testing of representative powdered infant formula samples using effective tests is required to provide information on contamination of infant formula with MAP, so that consumers can make informed decisions. This study aimed to test representative powdered infant formula samples for the presence of MAP using a quantitative PCR and liquid culture method. For this purpose, an efficient DNA extraction method was developed and an optimum decontamination protocol for culture method was identified. A total of 122 powdered infant formula samples were tested, comprising 72 brands produced by 12 manufacturers from 9 countries. Powdered infant formula samples were reconstituted and centrifuged to separate the casein pellet, cream layer and whey fraction. A sensitive qPCR test was performed on DNA extracted from the casein pellet. In addition, the cream layer and casein pellet were cultured in liquid media, following decontamination with the optimum protocol. Of the 122 samples tested, 6 were positive for MAP DNA but none were positive for growth in culture at 12 and 20 weeks. The limit of detection of the quantitative PCR was less than 5 MAP organisms per 1.5g milk powder. The methods developed in the study could be used for quality assurance testing for infant formula and calf milk replacers. The low contamination level of MAP and absence of viable forms in our study suggests a relatively low risk of exposure of infants to MAP components.

Reduction of Mycobacterium avium ssp. paratuberculosis in colostrum: Development and validation of 2 methods, one based on curdling and one based on centrifugation

The aim of this study was to develop and validate 2 protocols (for use on-farm and at a central location) for the reduction of Mycobacterium avium ssp. paratuberculosis (MAP) in colostrum while preserving beneficial immunoglobulins (IgG). The on-farm protocol was based on curdling of the colostrum, where the IgG remain in the whey and the MAP bacteria are trapped in the curd. First, the colostrum was diluted with water (2 volumes colostrum to 1 volume water) and 2% rennet was added. After incubation (1 h at 32°C), the curd was cut and incubated again, after which whey and curd were separated using a cheesecloth. The curd was removed and milk powder was added to the whey. Approximately 1 log reduction in MAP counts was achieved. A reduction in total proteins and IgG was observed due to initial dilution of the colostrum. After curd formation, more than 95% of the immunoglobulins remained in the whey fraction. The semi-industrial protocol was based on centrifugation, which causes MAP to precipitate, while the IgG remain in the supernatant. This protocol was first developed in the laboratory. The colostrum was diluted with skimmed colostrum (2 volumes colostrum to 1 volume skimmed colostrum), then skimmed and centrifuged (at 15,600 × g for 30 min at room temperature). We observed on average 1.5 log reduction in the MAP counts and a limited reduction in proteins and IgG in the supernatant. To obtain a semi-industrial protocol, dairy pilot appliances were evaluated and the following changes were applied to the protocol: after 2:1 dilution as above, the colostrum was skimmed and subsequently clarified, after which the cream was heat treated and added to the supernatant. To investigate the effect of the colostrum treatment on the nutritional value and palatability of the colostrum and the IgG transfer, an animal experiment was conducted with 24 calves. Six received the dam's colostrum, 6 were given untreated purchased colostrum (control), and 2 groups of 6 calves received colostrum treated according to both of the above-mentioned methods. No significant differences were found between the test groups and the dam's colostrum group in terms of animal health, IgG uptake in the blood serum, milk, or forage uptake. Two protocols to reduce MAP in colostrum (for use on-farm or at a central location) were developed. Both methods preserve the vital IgG.

Influence of milk, milk fractions and milk proteins on the growth and viability of mastitis-causing Staphylococcus aureus strain

The aim of this study was to investigate the impact of milk and milk fractions (cell-reduced, skim and whey) obtained from different cows on the growth rate of mastitis-causing Staphylococcus aureus strain at low inoculum density, simulating the early phase of intramammary infection. The association of the selected milk proteins, including α-lactalbumin, β-lactalbumin, lactoferrin, bovine serum albumin, γ-globulin and casein with the bacterial growth was also analysed. Twelve Polish Holstein-Friesian cows having no history of mastitis during the previous and current lactation were selected for this study. The S. aureus strain used in this study was isolated from a cow with clinical mastitis and was characterised by confirmed ability to spread among cows within a herd. Linear regression coefficients were calculated for associations between milk constituents and bacterial counts in whole milk as dependent variables. The comparison of bacterial growth between whole milk, cell reduced, skim and whey fractions was determined by a one-way analysis of variance (ANOVA). The results of the present study showed that the growth of mastitis-causing S. aureus was less stimulated by whole milk samples and their individual fractions in comparison to the nutrient microbiological medium. The strongest inhibition of bacterial growth was observed for whey fraction. Lactoferrin was the only protein causing a slight decrease in the growth of S. aureus. It was concluded that, depending on its growth medium and antimicrobial properties, milk may be among the factors of key importance for the incidence of this disease among individual cows.

Distribution of Animal Drugs among Curd, Whey, and Milk Protein Fractions in Spiked Skim Milk and Whey.

It is important to understand the partitioning of drugs in processed milk and milk products, when drugs are present in raw milk, in order to estimate the potential consumer exposure. Radioisotopically labeled erythromycin, ivermectin, ketoprofen, oxytetracycline, penicillin G, sulfadimethoxine, and thiabendazole were used to evaluate the distribution of animal drugs among rennet curd, whey, and protein fractions from skim cow milk. Our previous work reported the distribution of these same drugs between skim and fat fractions of milk. Drug distribution between curd and whey was significantly correlated (R2 = 0.70) to the drug's lipophilicity (log P), with improved correlation using log D (R2 = 0.95). Distribution of drugs was concentration independent over the range tested (20-2000 nM). With the exception of thiabendazole and ivermectin, more drug was associated with whey protein than casein on a nmol/g protein basis (oxytetracycline experiment not performed). These results provide insights into the distribution of animal drug residues, if present in cow milk, among milk fractions, with possible extrapolation to milk products.

Lactoferrin as an added therapy in the treatment of Helicobacter pylori

Background Bovine lactoferrin (bLF), an iron-binding glycoprotein, is a nonenzymatic antioxidant found in the whey fraction of fermented milk as well as in colostrum. The possibility that bLF may help improve the Helicobacter pylori eradication rate was first conceived in 1997 when an in-vitro study by Yamazaki and colleagues showed that bLF was bactericidal to H. pylori in Brucella broth. Later in-vitro studies have confirmed the same and yielded evidence of the possible mechanism of the bactericidal action of bLF, relating it to the high iron-binding affinity and prevention of iron utilization by H. pylori. Lactoferrin is used for treating stomach and intestinal ulcers, diarrhea, and hepatitis C. Aim The aim of the study was to verify the value of adding lactoferrin to the treatment of H. pylori infection. Patients and methods This study was conducted on 50 patients selected from Internal Medicine Department, Benha University Hospital. They were divided into group 1, which included 25 patients who were treated with traditional therapy (clarithromycin, omeprazole, amoxicillin, or metronidazole), and group 2, who were treated by traditional therapy plus lactoferrin (pravotin) for 1 week. H. pylori stool antigen testing was performed for both groups before and after therapy to assess the response to therapy. Results were statistically analyzed. Results Our results show that addition of lactoferrin improves the H. pylori infection eradication rate.

Novel angiotensin-converting enzyme inhibitory peptides from caseins and whey proteins of goat milk

Angiotensin-converting enzyme (ACE) plays a central role in blood pressure regulation by producing the vasoconstrictor angiotensin II. The inhibition of ACE with natural inhibitors, as alternatives to avoid the side effect of synthetic drugs, is a major target in the prevention of hypertension. In this study, we examined the separated caseins and whey proteins of goat milk for the presence of ACE inhibitory peptides. Digestion of isolated whey proteins and caseins of goat milk by gastric pepsin generated soluble hydrolysates exhibiting significant inhibition of ACE compared to weak inhibition by undigested proteins. The hydrolysates were fractionated by size exclusion chromatography, Sephacryl S-100 column, into four fractions (F1–F4). The late-eluting fraction (F4) of either whey or caseins exhibited greater ACE inhibition. Peptides in both F4 fractions, isolated by RP-HPLC, exhibited variable ACE inhibitory activities with the hydrophobic peptide peaks being the most potent ACE inhibitors. MALDI-TOF MS/MS resulted in identification of three potent ACE inhibitory peptides: PEQSLACQCL from β-lactoglobulin (residues 113–122), QSLVYPFTGPI from β-casein (residues 56–66), and ARHPHPHLSFM from κ-casein (residues 96–106). The peptides from whey and caseins exert significant ACE inhibitory activities comparable to that of captopril, an antihypertensive drug, exhibiting IC50 values of 4.45μM and 4.27μM, respectively. The results introduce, for the first time, new potent ACE-inhibitory peptides that can be released by gastric pepsin of goat milk whey and caseins and thus may pave the way for their candidacy as anti-hypertensive bioactive peptides and prevention of associated disorders.

Buffering curves of ideal whey fractions obtained from a cascade membrane separation process

Skimmed milk was fractionated via a cascade system: Graphic plotting of microfiltration (MF); ultrafiltration (UF); nanofiltration (NF); and reverse osmosis (RO). The buffering curves of each fraction were studied over the pH range 4–7. Depending on their composition, the individual permeate streams showed different buffering capacity values and pH ranges where the buffering occurred. The concentration of active buffering substances in the permeates decreased (in mmol/L) from ~26.6 (MF) to ~17.4 (UF) to 1.39 (NF) to 0.07 (RO). Contributions to the total buffering capacity for MF permeate, which represents the serum phase of milk, were ~37% from whey proteins and ~63% from milk salts (especially citrates, phosphates and carbonates) including lactose and water.

Characterization of Haptoglobin Isotype in Milk of Mastitis-Affected Cows.

Haptoglobin is a major acute phase protein in bovines and reportedly increases in serum and milk whey during mastitis, highlighting its potential as a diagnostic biomarker. Since haptoglobin is known to undergo tissue specific glycosylation resulting in different isoforms, this study was undertaken to characterize the isoforms of haptoglobin. Milk whey fraction and serum obtained from animals with or without clinical mastitis in Puducherry, India, were subjected to SDS-PAGE followed by western blot and immuno-detection of haptoglobin protein. All subunits (β, α1 and α2) of haptoglobin protein were detected in serum sample obtained from clinical cases. However, only the β-subunit was detected in milk whey fraction obtained from the respective animals. Similar results were observed with milk whey fractions from subclinical cases indicating difference in isoform of haptoglobin detected in milk whey from serum. This was further supported by RT-PCR (Reverse Transcription Polymerase Chain Reaction) analysis of haptoglobin gene (Hp) confirming the tissue specific origin of haptoglobin.

Effects of skim milk and whey-based milk replacers on feed intake and growth of dairy calves

ABSTRACTThe aim of this study was to provide information concerning calf performance when dairy calves are fed milk replacers (MR) in which skim milk powder is partly or completely replaced by whey products and wheat protein. A feeding experiment comprised 30 dairy bull calves. During the pre-weaning the calves received three different MRs. The main ingredients of MR1 were skim milk powder (418 g/kg dry matter), whey powder (409) and vegetable oil (163). MR2 included less skim milk powder (300) compared to MR1 including whey powder (283), vegetable oil (190), whey fractions (100), hydrolysed wheat protein (65) and wheat starch (50). MR3 did not include skim milk powder while the main ingredients were whey powder (448), whey fractions (300) vegetable oil (160) and hydrolysed wheat protein (70). Live weight gain of the MR2 calves was 14% higher compared to the MR3 calves during the pre-weaning but there were no differences when compared MR1 calves to other treatments. No treatment differences were observed in gain during post-weaning or average during the experiment. There were no differences in feed conversion among treatments. The results indicated that both skim milk powder and whey-based products were suitable energy sources in MR.

Whey fractionation through the membrane separation process

ABSTRACTThe aim of this work is to improve the utilisation of fractions of whey through membrane separation processes. From a solution of whey treated by ultrafiltration (UF) associated with diafiltration (DF), two streams were obtained: a concentrate and a permeate. In this process, a purified protein concentrate with about 70% of protein was obtained. Permeate was treated by electrodialysis (ED) to obtain a fraction rich in lactose (90%). The final effluent was treated by reverse osmosis (RO) in order to recover water free of salts. RO made it possible to recover 50% water and retain 85% of the salts.

Impact of Protein Removal by an Upstream Ultrafiltration on the Reverse Osmosis of Skim Milk and Sweet Whey

AbstractConcentration of milk and whey by ultrafiltration and reverse osmosis (RO) in cascade mode is an amendment of evaporation for high volume reduction ratios (VRR) prior to drying. This study investigated the impact of a prior protein removal and the transmembrane pressure (TMP) on the RO stage, compared to skim milk and sweet whey. It could be found that removal of the protein fraction of both skim milk and sweet whey improved the efficiency of the RO. An upstream ultrafiltration resulted in higher VRR as well as an increased permeate flux.

Fractionation of sheep cheese whey by a scalable method to sequentially isolate bioactive proteins

This study reports a procedure for the simultaneous purification of glyco(caseino)macropeptide, immunoglobulin, lactoperoxidase, lactoferrin, α-lactalbumin and β-lactoglobulin from sheep cheese sweet whey, an under-utilized by-product of cheese manufacture generated by an emerging sheep dairy industry in New Zealand. These proteins have recognized value in the nutrition, biomedical and health-promoting supplements industries. A sequential fractionation procedure using economical anion and cation exchange chromatography on HiTrap resins was evaluated. The whey protein fractionation is performed under mild conditions, requires only the adjustment of pH between ion exchange chromatography steps, does not require buffer exchange and uses minimal amounts of chemicals. The purity of the whey protein fractions generated were analyzed by reversed phase-high performance liquid chromatography and the identity of the proteins was confirmed by mass spectrometry. This scalable procedure demonstrates that several proteins of recognized value can be fractionated in reasonable yield and purity from sheep cheese whey in one streamlined process.

Antioxidant activity of camel and bovine milk fermented by lactic acid bacteria isolated from traditional fermented camel milk (Chal)

Chal is a traditional fermented product produced from spontaneously fermented camel milk which contains several bacterial species with potential usage in producing traditional dairy products and functional foods. The aims of this study were to isolate and identify predominant lactic acid bacteria (LAB) from Chal and investigate antioxidant activity of camel and bovine milk fermented by these isolates. Chal samples were collected from Turkman Sahra, Golestan Province, Iran. The protein hydrolysis was determined by o-phthaldialdehyde (OPA) method, and antioxidant activities of whey fractions were evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radicals scavenging methods. Nine catalase-negative bacteria including Lactobacillus (L.) plantarum, L. paraplantarum, L. kefiri, L. gasseri, L. paracasei, Leuconostoc (Leu.) lactis, Weissella (W.) cibaria, and Enterococcus (E.) faecium were isolated and identified by conventional and molecular methods. Both camel and bovine milk were fermented by the strains for 24 h. Fermented camel milk showed significantly (P < 0.05) higher antioxidant activity than bovine milk. Camel milk fermented by Leu. lactis showed significantly (P < 0.05) higher DPPH (57.90 ± 4.59 μM) and ABTS (1484.35 ± 128.20 μM; P < 0.05) radical scavenging activity compared to samples fermented by other strains. According to sensory evaluation of fermented camel and bovine milks, camel milk fermented by Leu. lactis SM10 had the highest overall acceptance values. Our findings suggest that camel and bovine milk fermented by LAB isolated from Chal could potentially be used for producing novel functional foods.