Production of Whey Protein-Based Aggregates Under Ohmic Heating

Pereira, Ricardo N.; Rodrigues, Rui M.; Ramos, Óscar L.; Malcata, F. Xavier; Teixeira, J. A.; Vicente, António A.

doi:10.1007/s11947-015-1651-4

Cited by 75 publications

(56 citation statements)

References 57 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The CA values which lead us to conclude that the presence of MEF changes the way that the polysaccharides structure is distributed in the films. Electrical disturbance of MEF can impose reorientation of molecules was described elsewhere (Pereira et al, 2016). In this case, these events may have reduced the exposure of hydrophilic groups.…”

Section: Discussionmentioning

confidence: 84%

Effect of moderate electric fields in the properties of starch and chitosan films reinforced with microcrystalline cellulose

Coelho

Cerqueira

Pereira

et al. 2017

Carbohydrate Polymers

Self Cite

View full text Add to dashboard Cite

Microcrystalline cellulose (MCC) can provide improved properties when the aim is the development of biodegradable packaging materials. In this work the physicochemical properties of polysaccharide-based films (chitosan and starch) with the incorporation of MCC and the application of moderate electric field (MEF) and ultrasonic bath (UB) as treatments, were evaluated. For each treatment, the thickness, moisture content, solubility, water vapor permeability, contact angle, mechanical properties, along with its color and opacity were determined. The surface morphologies of the films were assessed by scanning electron microscopy (SEM). X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA) were also performed. It was observed that the addition of different concentrations of MCC as well as the application of MEF are responsible for changes in the properties of the films, being this effect dependent on the polysaccharide used. Chitosan-based films were slightly yellow, transparent and presented a more homogeneous structure. The use of MEF was efficient in decreasing the permeability to water vapor in chitosan based films without MCC, as well as in production of films with a more hydrophobic surface. The addition of MCC promoted more opaque, rigid, less flexible and less hydrophobic films. Starch-based films were whitish, with a more heterogeneous structure and the application of MEF generated more hydrophilic films with lower tensile strength and Young's modulus. The films with MCC were more opaque, less flexible and less hydrophilic than the films without MCC. The composites presented good thermal properties, which increases their applicability as packaging materials. Therefore, the incorporation of MCC into polysaccharide-based films as well as the application of MEF can be an approach to change the properties of films.

show abstract

Section: Discussionmentioning

confidence: 84%

Effect of moderate electric fields in the properties of starch and chitosan films reinforced with microcrystalline cellulose

Coelho

Cerqueira

Pereira

et al. 2017

Carbohydrate Polymers

Self Cite

View full text Add to dashboard Cite

show abstract

“…The electro-heating treatments were performed in a jacketed static ohmic heater as described elsewhere (Pereira et al, 2015;Pereira, Souza, Cerqueira, Teixeira, & Vicente, 2010). The distance between electrodes was kept constant, and the voltage varied in the power source working with a sinusoidal wave at 25 kHz (1 Hze25 MHz and 1e10 V; Agilent 33220A, Penang, Malaysia).…”

Section: Methodsmentioning

confidence: 99%

Effects of ohmic heating on extraction of food-grade phytochemicals from colored potato

Pereira

Rodrigues

Genisheva

et al. 2016

LWT

Self Cite

View full text Add to dashboard Cite

a b s t r a c tThe influence of ohmic heating (OH) through the application of moderate electric fields on phytochemical compounds recovery from colored potato (Solanum tuberosum L. var. Vitelotte) was studied. A BoxeBehnken design was used to simultaneously assess the effects of operational parameters such as electric field strength, temperature and process time on the yields of anthocyanins and total phenolic recovery on pretreatment of potato samples. From the analysis of the model, electric field, temperature and time were shown to have independent and interactive effects on the values of extraction yields. Aqueous extraction of phytochemical compounds after pretreatments can be described by using a twostep model involving simultaneous washing and diffusion of the solutes from the samples. Results shows that electrical fields of low energy levels and thermal effects can be combined and optimized into a single step treatment on extraction of anthocyanins and phenolic compounds from vegetable tissues providing high recovery yields with a reduced treatment time, less energy consumption and with no utilization of organic solvents (green extraction).

show abstract

“…The measurements were made at room temperature (ca. 25°C) according with the procedure reported by Pereira et al (2015) resorting to a 10 mm path length cuvette, and with 25 mmol L −1 sodium phosphate sodium buffer as blank. The measurements were performed in triplicate and experimental values are presented as the average ± standard deviation.…”

Section: Turbiditymentioning

confidence: 99%

Design of β-lactoglobulin micro- and nanostructures by controlling gelation through physical variables

et al. 2020

Self Cite

View full text Add to dashboard Cite

A B S T R A C Tβ-lactoglobulin (β-Lg) is the major protein fraction of bovine whey serum and its principal gelling agent. Its gelation capacity enables conformational changes associated with protein-protein interactions that allow the design of structures with different properties and morphologies. Thus, the aim of this work was to successfully use β-Lg, purified from a commercial whey protein isolate, to develop food-grade micro-(with diameters between 200 and 300 nm) and nano-(with diameters ≤ 100 nm) structures. For this purpose, the phenomena involved in β-Lg gelation were studied under combined effects of concentrations (from 5 to 15 mg mL −1 ), heating temperature (from 60 to 80°C) and heating time (from 5 to 25 min) for pH values of 3, 4, 6 and 7. The effects of such conditions on β-Lg structures were evaluated and the protein was fully characterized in terms of size, polydispersity index (PDI) and surface charge (by dynamic light scattering -DLS), morphology (by transmission electron microscopy -TEM) and conformational structure (circular dichroism, intrinsic and extrinsic fluorescence). Results have shown that β-Lg nanostructures were formed at pH 3 (with diameters between 12.1 and 22.3 nm) and at 7 (with diameters between 8.9 and 35.3 nm). At pH 4 structures were obtained at macroscale (i.e., ≥ 6 μm) for all β-Lg concentrations when heated at 70 and 80°C, independent of the time of heating. For pH 6, it was possible to obtain β-Lg structures either at micro-(245.0 -266.4 nm) or nanoscale (≤ 100 nm) with the lowest polydispersity (PDI) values (≤ 0.25), in accordance with TEM analyses, for heating at 80°C for 15 min. Intrinsic and extrinsic fluorescence data and far-UV circular dichroism spectra measurements revealed conformational changes on β-Lg structure that support these evidences. A strict control of the physical and environmental conditions is crucial for developing β-Lg structures with the desired characteristics, thus calling for the understanding of the mechanisms of protein aggregation and intermolecular interaction when designing β-Lg structures with novel functionalities.

show abstract

Production of Whey Protein-Based Aggregates Under Ohmic Heating

Cited by 75 publications

References 57 publications

Effect of moderate electric fields in the properties of starch and chitosan films reinforced with microcrystalline cellulose

Effect of moderate electric fields in the properties of starch and chitosan films reinforced with microcrystalline cellulose

Effects of ohmic heating on extraction of food-grade phytochemicals from colored potato

Design of β-lactoglobulin micro- and nanostructures by controlling gelation through physical variables

Contact Info

Product

Resources

About