Study of the Different Ways of Proteins Extraction From Sheep and Cow Whey for “Urda” Cheese Production

The necessary stage of technological process of “Urda” albumin cheese production is whey proteins extraction from sheep whey (in classic technology of product) or from the whey mixtures, offered in the work. For whey proteins extraction from whey the following ways are used: thermal, acid, acid-alkaline and chlorine-calcium.There was established the equal dependence of the influence of the way of proteins extraction from both sheep and cow whey on the output of protein mass.The most output of protein mass (3,47±0,10 %) is at the chlorine-calcium way of proteins extraction, a bit less – 3,41±0,08 % – at the acid-alkaline way. But the acidity of such protein mass, received by the chlorine-calcium and acid-alkaline ways is not high – 37,2±1,8 and 45,6±1,4 % respectively that negatively influences the gustatory qualities of product. The least output is registered at the thermal way. Albumin cheese, received from such protein mass, was the best by its gustatory qualities. The output of protein mass from sheep whey is 1,60 times higher than from cow whey. The mass share of proteins in protein mass, received from sheep whey is by 6,9…8,0 % higher comparing with one, received from cow whey.Protein mass, received from sheep whey by the chlorine-calcium and acid-alkaline ways has the low titrated acidity. Cheese, received from protein mass, received of sheep whey by the acid method, has the extremely high acidity values (115,5±1,5 °Т), excessive sour-milk flavor and smell. These results don-t allow to provide the long storage term. That is why it is recommended to use the thermal way for proteins extraction from sheep whey and for proteins extraction from cow way in the technology of “Urda” albumin cheese.So the thermal way of proteins extraction from the mixture of sheep and cow whey in ratio 1:1 or 3:1 can be used for “Urda” albumin cheese production. The use of cow whey gives a possibility to cheapen the product because cow whey is cheaper than sheep one. Such cheese has the improved organoleptic parameters, namely homogenous consistence, tender sour-milk flavor and smell

Fluorescence-based analyser as a rapid tool for determining soluble protein content in dairy ingredients and infant milk formula

peer-reviewedAbstract: Milk protein, in particular native whey protein, is of interest to dairy manufacturers as a measure of functional and nutritional quality. However, quantification of soluble whey protein (SP) is time consuming; giving rise to the need to develop rapid, accurate, and portable at-line process analytical technology. In this study, the performance of a fluorescence-based analyser(F) (Amaltheys II, Spectralys Innovations, France) was evaluated for quantification of SPF and whey protein nitrogen index (WPNI)F in skim milk, whey protein concentrate and infant formula powders. Rehydration of powders prior to analysis was a key factor for ensuring repeatability and reproducibility. A comparison of the analyser with reference methods for SPF and WPNIF resulted in coefficient of determination (R2) > 0.993 for both SPKjeldahl method and WPNIGEA. The results show the fluorescence-based analyser to be rapid, compact, and accurate device, suited for providing reliable support to dairy ingredient and infant formula manufacturers. Industrial relevance: The fluorescence based analysis investigated in this article is suitable for application in the dairy industry where it can be used as a rapid, at-line PAT tool for both liquid and powder samples. The technology has the potential to replace well-established methods for measurement of soluble protein. The main benefit to industry is the ability to respond more rapidly to variations in soluble protein without compromising on the accuracy associated with more time consuming methods

Selective removal of fat from acid whey during whey protein concentrate manufacture : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Technology in Food Technology

The purpose of this study was to develop a low cost technology for selective removal of lipids from acid whey during whey protein concentrate manufacture Attention was focused on gaining a better understanding of the structure and composition of the lipids in whey and ultrafiltration retentate The effects of varying dilutions, pH, salt concentration, temperature and holding time on the flocculation of lipids in the whey and retentate were investigated The composition and structure of lipids in acid whey and retentate were determined by ultracentrifugation, compositional analysis, integrated light scattering and confocal scanning laser microscopy (CLSM) techniques. Acid whey contained ~ 0.034% lipids The size of the milk fat globules (MFG) in whey varied from 0.1 and 10 μm. with the majority of the globules < 1 μm in diameter The retentate contained ~ 0.36% lipids The size of the MFG in the retentate ranged between 0.1 and 20 μm. generally larger than the MFG in the acid whey Investigation into the removal of lipids from acid whey revealed that flocculation of MFG in the acid whey occurred at temperatures between 40 and 50°C and at pH values from 5.8 to 7.0. It was observed that under these conditions, high-density lipid containing flocculent/precipitates was formed, which subsequently sedimented upon centrifugation (at 1126/g for 10 min) The MFG removed in the flocculent/precipitate appears to be either part of a calcium-MFG complex or MFG entrapped by precipitation of calcium precipitate Examination of the effects of physiochemical factors on the flocculation of MFG in between the retentate revealed that flocculation occurred upon dilution and at pH values between 4.5 and 4.7. It was found that at increasing dilutions, there was an increase in the removal of MFG and in the retention of protein in the supernatant. At retentate dilution of 1:6, the majority of the MFG was removed and a majority of protein was retained in the supernatant Flocculation of MFG in the diluted retentate was influenced by ionic strength (at Low pH values) of the system. This flocculation is thought to result from the hydrophobic association of proteins of MFGM, aggregates of serum proteins, lipoprotein complexes or individual denatured serum proteins Low fat whey protein concentrate powder (WPC) was produced on a pilot-scale plant using the process conditions determined at the laboratory scale to remove MFG from acid whey retentate. The resulting product contained ~ 1% fat. considerably less than the normal commercial WPC On a dry basis the protein content was ~ 96% as compared to ~ 85% in the commercial WPC Examination of the functionality of the low fat WPC revealed the heat-induced gels formed from 15% WPC were more elastic, had better water holding capacity, and were more "gelatinous" in nature Their gelation properties were markedly superior to the commercial WPCs currently manufactured Based on the results of this study, recommendations are made on possible areas of process improvement and development opportunities

Whey- vs Casein-Based Enteral Formula and Gastrointestinal Function in Children With Cerebral Palsy.

Objectives: Children with severe cerebral palsy (CP) commonly have gastrointestinal (GI) dysfunction. Whey-based enteral formulas have been postulated to reduce gastroesophageal reflux (GOR) and accelerate gastric emptying (GE). The authors investigated whether whey-based (vs casein-based) enteral formulas reduce GOR and accelerate GE in children who have severe CP with a gastrostomy and fundoplication. Methods: Thirteen children received a casein-based formula for 1 week and either a 50% whey whole protein (50% WWP) or a 100% whey partially hydrolyzed protein (100% WPHP) formula for 1 week. Reflux episodes, gastric half-emptying time (GE t1/2), and reported pain and GI symptoms were measured. Results: Whey formulas emptied significantly faster than casein (median [interquartile range (IQR)] GE t1/2, 33.9 [25.3-166.2] min vs 56.6 [46-191] min; P = .033). Reflux parameters were unchanged. GI symptoms were lower in children who received 50% WWP (visual analog symptom score, median [IQR], 0[0-11.8]) vs 100% WPHP (13.0 [2.5-24.8]) (P = .035). Conclusion: This pilot study shows that in children who have severe CP with a gastrostomy and fundoplication, GE of the whey-based enteral formula is significantly faster than casein. The acceleration in GE does not alter GOR frequency, and there appears to be no effect of whey vs casein in reducing acid, nonacid, and total reflux episodes. The results indicate that enteral formula selection may be particularly important for children with severe CP and delayed GE. (JPEN J Parenter Enteral Nutr. 2012;36:118S-123S

Stability of whey protein derived peptides upon severe protein glycation

Cow’s milk and dairy products are major nutrients in the human diet, especially during infancy. Though at one time whey proteins were considered as by-product of the cheese making process, nowadays, due to their wide ranging nutritional, biological, and functional properties, whey proteins are often used in food technology as low-cost protein ingredients. However, whey-protein fractions, such as β-lactoglobulin (β-LG) and α-lactalbumin (α-LA) represent the major allergens in cow’s milk. Therefore, the use of whey proteins in food might pose a serious threat to the milk allergic consumers. It is well reported that food processing may modify the allergenicity and detectability of proteins. This can be due to hydrolysis or chemical reactions with other food components (carbohydrates, fatty acids etc), leading to modification or destruction of the allergen’s structure. Therefore, the objective of this study was in the first stage to investigate the influence of glycation on the molecular changes induced in whey proteins. This was done with a special focus on the modifications induced on the lysine residues, free amino groups, the formation of protein bound carbonyls, formation of fluorescent compounds and brown polymers and on the protein aggregation. Matrix-assisted laser desorption/ionization - time of flight mass spectrometry (MALDI-TOF MS) was used to get a better insight into the molecular changes that took place on the protein level. Unexpectedly, this study led to the identification of protein segments in the epitope region that remained unmodified during the experiments that mimic typical food processing conditions. The 57Val – Lys76 and 31Val – Arg56 from β–LG, remained unchanged disregarding the severe heating treatment in the presence of glucose and bulk proteins and they could be identified by either direct MALDI-TOF MS and MS/MS or after a more tedious separation using reversed phase chromatography. It is proposed that these peptide segments can be used as analytical targets for the development of more robust methods for the assessment of the presence of whey proteins in processed foodstuffs. Moreover, MALDI-TOF MS and MS/MS holds potential to be used as a screening tool for the identification of such stable peptides

Two phase aqueous extraction of whey proteins in a polyethylene glycol - arabinogalactan system

The whey protein separation potential of aqueous two-phase systems of arabinogalactan [AG] (Lonza FiberAidTM) and polyethylene glycol [PEG], buffered with 10 mmol/g phosphate or citrate buffer, was studied. 100 mmol/g potassium chloride [KCl] was added as required. Previously-published phase equilibrium results were verified and the absorbance of whey protein isolate [WPI] in an AG-PEG solution was measured. The effect of pH, KCl concentration, initial WPI concentrations and upper to lower phase mass ratios on whey partitioning was studied. The best separation system contained 17.20% (w/w) AG, 7.20% (w/w) PEG, 10 mmol citrate buffer (pH 5.4) and 100 mmol KCl per gram of total system. The upper to lower phase mass and volume ratios were 1:1 and 16:11 respectively. Approximately 12 mg (mainly α-lactalbumin) of the 20 mg WPI added partitioned into the AG-rich upper phase. This system has potential to reduce chromatographic requirements in large scale separation of protein mixtures

Development of a high protein snack food containing whey protein concentrate

Objectives of this study were to recover protein from cottage cheese whey and develop whey protein concentrate into an acceptable textured protein food product. Cottage cheese whey was treated with sodium hexametaphosphate to precipitate whey protein-HMP complex. The protein recovery was improved by treating whey with an ion exchange resin, but the treatment caused some loss of total protein. Commercial whey protein concentrate was used to prepare a deep fried snack product which was dusted with three different flavors. The deep fried, flavored snack products had desirable texture and flavor. These flavors can be varied for a variety of tastes. Sensory evaluation showed that the textured protein snack food fortified with whey protein was highly acceptable

Determination Methods Of Defrosted Protein-vegetable Mixtures Parameters Development

The aim of the work is to develop methods of investigating the influence of semolina and extruded semolina on quality and quantity parameters of mixtures with milk-protein concentrates in a cycle of freezing-defrost that allows to substantiate resource-saving in semi-products manufacturing.Obtained results of changes of the quality of protein-vegetable mixtures after the effect of negative temperatures confirm cryo-protective properties of carbohydrates of products of wheat processing.There were studied methods of extracting proteins of whey for getting albumin mass and using in the composition of milk-protein concentrates. It was established, that adding collagen-containing ingredients in amount 0,4 % for intensifying thermal coagulation of whey proteins decreases the duration of precipitation to (55±2) and (40±2) min respectively depending on a type of raw material processing. There were studied both native whey and protein concentrate, obtained by the method of ultra-filtration with mass share of dry substances (16±2) %.The method of thermal analysis determined a cryoscopic temperature of sour-milk fatless cheese and also albumin mass, obtained using «Collagen pro 4402». The calculation method, based on cryoscopic temperature indices determined an amount of moisture, frozen out in milk-whey mixtures with wheat processing products. The presented information is enough for estimating traditional modes of freezing milk-protein concentrates objectively.The obtained results of the studies indicate the effectiveness of the offered methods for determining parameters of protein-vegetable mixtures after defrosting. Measurements of quality parameters may be used for correcting mass losses of concentrates effectively

Macromolecular interactions during gelatinisation and retrogradation in starch-whey systems as studied by rapid visco-analyser

Gelatinisation and retrogradation of starch-whey mixtures were studied in water (pH 7) using the Rapid Visco-Analyser (RVA). The starch:whey ratios ranged from 0:100 - 100:0. Wheat starch, and whey protein concentrate (about 80% solids basis) and isolate (about 96% solids basis) were used. Mixtures with whey isolates were generally more viscous than those with whey concentrates, and this was attributed to fewer non-protein milk components in the former. Whey protein concentrates and isolates reduced the peak, trough and final viscosities of the mixtures, but the breakdown and setback ratios of the mixtures were increased. The gelatinisation temperature increased with whey substitutions indicating that whey protein delayed starch gelatinisation. The temperature of fastest viscosity development decreased as the amount of whey was increased. Whey protein isolate generally exercised a lesser effect than the concentrate. At between 40 - 50% whey substitutions, the dominant phase changed from starch to protein irrespective of the source of the whey protein. An additive law poorly defined selected RVA parameters. Both macromolecules interacted to define the viscosity of the mixture, and an exponential model predicted the viscosity better than the additive law. The results obtained in this study are discussed to assist the understanding of extrusion processing of starch-whey systems as models for whey-fortified snack and ready-to-eat foods. Copyright ©2006 The Berkeley Electronic Press. All rights reserved

Impact of sodium alginate on binary whey/pea protein-stabilised emulsions

This study aims to understand impact of sodium alginate addition on binary whey/pea protein-stabilised emulsions at various pH. The properties and stability of binary whey/pea protein-stabilised emulsions were characterised by microstructural analysis, droplet size, creaming index in comparison to sole proteins. Protein composition at oil/water interface was examined via SDS-PAGE. Alginate incorporation reduced the droplet sizes and enhanced the emulsion stability at pH 6.6. At pH 11.0, protein only-stabilised emulsion was stable for 21 days, while alginate addition resulted in phase separation in the binary whey/pea protein-stabilised emulsions. The presence of alginate promoted protein adsorption at all pH with both proteins present at the interface. Whey protein displaced pea protein in the binary whey/pea protein-stabilised emulsions over time, whereas alginate addition prevented pea protein from being replaced by whey protein during storage, enhancing their stability. Binary whey/pea proteins with sodium alginate are promising emulsifiers with potential application for liquid creamers