Influence of novel food processing technologies on the rheological and thermophysical properties of whey proteins

Rabbit myosin (20 mg/mL of 0.6 M NaCl, pH 6.5) was subjected to various pressures (100–400 MPa) at 20 °C for 10 min to investigate pressure-induced gel mechanism by measurements of protein surface hydrophobicity, sulfhydryl contents, molecular size by native polyacrylamide gel electrophoresis, ultra-structure using SEM, and viscoelastic properties by dynamic rheology. Surface hydrophobicity and sulfhydryl groups had little increase at 100 and 200 MPa, but had significant increase at 300 and 400 MPa. Ultra-structure revealed that gels below 200 MPa were filament structure with many small cavities, while gels upon 300 MPa were globular aggregates with big cavities. Dynamic rheological measurements indicated that gels were formed at 400 MPa. Mechanism of myosin gel formation in pressure treatment was that myosin was unfolded, following the exposure of hydrophobic and buried sulfhydryl groups, then was denatured (electrophoresis showed the heavy chain became very weak) and associated to form gels. Industrial relevance In recent years, high pressure treatment of food has received interest as an alternative to heat treatment for gel formation. Gel-type meat products of high pressure processing are still not commercialized. This is basically due to lack of information about high pressure-induced gel. Myosin is the protein responsible for the gelling capacity of muscle systems. The processing characteristics of gels treated by high pressure were improved. The results of this experiment showed that myosin denatured and formed gels at pressure 400 MPa holding for 10 min. This information will help industry to adopt high pressure to produce meat products.

The mechanism of high pressure-induced gels of rabbit myosin

Effects of sucrose on egg white protein and whey protein isolate foams: Factors determining properties of wet and dry foams (cakes)

Effects of autoclaving temperature and storing time on resistant starch formation and its functional and physicochemical properties.

Numerous why protein products (WPP) have been developed as excellent food ingredients with unique functional properties. However, the functional properties of WPP are affected by several compositional and processing factors. Recently, novel processing technologies such as high hydrostatic pressure, ultrasound, extrusion and tribomechanical activation have been used to modify the functional properties of WPP. Also, WPP have been used as delivery systems for functional ingredients and in edible films. The present paper reviews the latest developments in the role of different factors on the functional properties of WPP with emphasis on novel processing technologies, and interaction with other food ingredients

Factors Affecting the Functional Properties of Whey Protein Products: A Review

Effect of carbohydrates on the emulsifying, foaming and freezing properties of whey protein suspensions

L'objectif de cette etude etait d'evaluer l'influence des traitements haute pression sur la solubilite, l'hydrophobicite de surface, le pouvoir moussant et emulsifiant d'un concentre (WPC) et d'un isolat (WPI) de proteines de lactoserum. Les dispersions de poudres WPC ET WPI (10 % w/w) etaient traitees a 300 MPa et 600 MPa pendant 5 et 10 min, a 40 ± 2 °C. Les changements de solubilite des proteines etaient determines a pH 7.0 et a pH 4.6. L'evaluation des proprietes moussantes etait basee sur l'expansion de la mousse au cours d'un fouettage prolonge et sur la stabilite de mousse. Les proprietes emulsifiantes etaient caracterisees par la stabilite de l'emulsion et les indices d'activite emulsifiante. Les resultats ont montre une modification significative (P < 0,05) de la solubilite et de l'hydrophobicite de surface avec l'application d'une pression de duree et d'intensite croissantes, indiquant une denaturation partielle et l'agregation des proteines. Il a ete demontre que les traitements haute pression amelioraient de facon significative (P < 0,05) le comportement moussant de l'isolat de proteines de lactoserum, tandis que la capacite moussante du concentre de proteines etait diminuee. Cependant, les mousses formees avec le WPC et le WPI traites par haute pression montraient une stabilite significativement prolongee (P < 0,05) par rapport au temoin. Une tendance significative a la diminution de l'efficacite emulsifiante et de la stabilite de l'emulsion, liee a l'intensite de la pression appliquee et de la duree de traitement, etait observee aussi bien pour le WPC que le WPI.

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Effects of high pressure on functionality of whey protein concentrate and whey protein isolate

Whey proteins are commonly used in the food industry due to their nutritive value and functional properties. The most important functional properties of whey proteins are solubility, viscosity, water holding capacity, emulsification and foaming. The aim of this study was to determine functional properties of main whey protein fractions ( α -lactalbumin and β -lactoglobulin) which have the biggest influence on the functional properties of whey proteins. Particle size analysis and specific area of α -lactalbumin and β -lactoglobulin were performed by «Mie – theory» of «light scatering» using «Malvern Mastersizer X». The results of this analysis have shown that β -lactoglobulin had higher particle size and specific area than α -lactalbumin. By examining functional properties (solubility, dispersibility, emulsifiying properties – emulsion activity index (EAI) and emulsion stability index (ESI) and foaming properties) of α -lactalbumin and β -lactoglobulin, it has been established that

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Funkcionalna svojstva α-laktalbumina i β-laktoglobulina

Summary The aim of this study was to determine functional properties: solubility, dispersibility, viscosity, emulsifiying, foaming and rheological properties of hydrolyzed whey protein (HWP) and whey protein isolate (WPI). Particle size analysis and specific area of HWP and WPI were performed by «Mie – theory» of «light scatering» using «Malvern Mastersizer X». The results of this analysis have shown that HWP had higher particle size and specific area than WPI. By examing functional properties, it has been established that HWP has higher solubility, dispersibility, emulsifiying properties as well as foam stability (FSI and MFS) compared to WPI. Rheological properties of protein suspensions were determined in 10, 15, and 18 % suspension of proteins (HWP and WPI) by rotational viscosimeter, Brookfiel DV-III at 25 ° C. Apparent viscosity at 200 s -1 was calculated, using Newtonian law. On the basis of measured shear rate and shear stress, using least squere method, rheological parameters, flow behavior indeks (n) and consistency coefficient (k) were determined according to the Ostwald de

/pdf/funkcionalnost-izolata-i-hidrolizata-proteina-sirutke-2d0isrjq3e.pdf

Funkcionalnost izolata i hidrolizata proteina sirutke

Proteini sirutke cine 18 - 20 % ukupnih proteina mlijeka. Njihova nutritivna vrijednost, uz raznolika fizikalno-kemijska i funkcionalna svojstva, cine proteine sirutke siroko primjenjivim u prehrambenim proizvodima. Proteini sirutke najcesce se koriste zbog poželjnih funkcionalnih svojstava. Mogu se koristiti kao sredstva za želiranje, za vezivanje vode, emulgiranje te stvaranje pjene. Zahvaljujuci primjeni novih procesnih tehnika (membranskih tehnika frakcioniranja), danas je moguce proizvesti razlicite dodatke hrani na bazi proteina sirutke. Najvažniji proizvodi na bazi sirutkinih proteina su koncentrati i izolati proteina sirutke. Svrha ovog rada je dati sveobuhvatan pregled hranjivih i funkcionalnih svojstava najcesce upotrebljavanih oblika proteina sirutke (koncentrata proteina sirutke - KPS i izolata proteina sirutke - IPS) u prehrambenoj industriji.

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Anet Režek

Papers

Effect of carbohydrates on the emulsifying, foaming and freezing properties of whey protein suspensions

Effects of high pressure on functionality of whey protein concentrate and whey protein isolate

Funkcionalna svojstva α-laktalbumina i β-laktoglobulina

Funkcionalnost izolata i hidrolizata proteina sirutke

Nutritional and functional properties of whey proteins concentrate and isolate