Rennet coagulation properties of milk in the presence of oil droplets stabilised by a combination of sodium caseinate and whey protein isolate

SummaryBoth whey protein isolate (WPI) and Na caseinate gave similar emulsion capacity-concentration profiles at pH 7. The emulsion capacity of aqueous solutions of WPI was relatively independent of pH while the values for caseinate fell in the isoelectric region. Saline (7·59 g/1) compared with aqueous solutions improved emulsion capacity, particularly above pH 7. At low concentration, WPI had greater emulsifying capacity and gave finer globule dispersion than sodium caseinate. Increase in emulsifier concentration, within a certain range, increased stability, improved dispersion and reduced capacity. Ethanol up to about 20% w/w improved the emulsion capacity of both proteins while at 50% the phases separated. Heat treatment (> 65 °C) of WPI solution before emulsion formation impaired capacity and stability. Heat treatment of preformed WPI emulsions did not have the same effect. Na caseinate and WPI each formed a thin continuous layer of relatively uniform thickness over the oil globule surfaces while denatured WPI appeared aggregated and relatively unevenly distributed at the oil-aqueous interface.

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Whey protein isolate-lignin complexes as encapsulating agents for enhanced survival during spray drying, storage, and in vitro gastrointestinal passage of Lactobacillus reuteri KUB-AC5

LWT ◽

10.1016/j.lwt.2021.111725 ◽

2021 ◽

pp. 111725

Author(s):

Phùng Diệp Huy Vũ ◽

Akkaratch Rodklongtan ◽

Pakamon Chitprasert

Keyword(s):

Whey Protein ◽

Spray Drying ◽

Lactobacillus Reuteri ◽

Whey Protein Isolate ◽

Protein Isolate

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Fabrication of Oil-in-Water Emulsions with Whey Protein Isolate–Puerarin Composites: Environmental Stability and Interfacial Behavior

Foods ◽

10.3390/foods10040705 ◽

2021 ◽

Vol 10 (4) ◽

pp. 705

Author(s):

Yejun Zhong ◽

Jincheng Zhao ◽

Taotao Dai ◽

Jiangping Ye ◽

Jianyong Wu ◽

...

Keyword(s):

Interfacial Tension ◽

Whey Protein ◽

Surface Protein ◽

Whey Protein Isolate ◽

Protein Isolate ◽

Environmental Stability ◽

Dependent Manner ◽

Emulsifying Properties ◽

Interfacial Behavior ◽

Concentration Dependent Manner

Protein–polyphenol interactions influence emulsifying properties in both directions. Puerarin (PUE) is an isoflavone that can promote the formation of heat-set gels with whey protein isolate (WPI) through hydrogen bonding. We examined whether PUE improves the emulsifying properties of WPI and the stabilities of the emulsions. We found that forming composites with PUE improves the emulsifying properties of WPI in a concentration-dependent manner. The optimal concentration is 0.5%, which is the highest PUE concentration that can be solubilized in water. The PUE not only decreased the droplet size of the emulsions, but also increased the surface charge by forming composites with the WPI. A 21 day storage test also showed that the maximum PUE concentration improved the emulsion stability the most. A PUE concentration of 0.5% improved the stability of the WPI emulsions against environmental stress, especially thermal treatment. Surface protein loads indicated more protein was adsorbed to the oil droplets, resulting in less interfacial WPI concentration due to an increase in specific surface areas. The use of PUE also decreased the interfacial tension of WPI at the oil–water interface. To conclude, PUE improves the emulsifying activity, storage, and environmental stability of WPI emulsions. This result might be related to the decreased interfacial tension of WPI–PUE composites.

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Effect of thermally induced denaturation on molecular interaction-response relationships of whey protein isolate based films and coatings

Progress in Organic Coatings ◽

10.1016/j.porgcoat.2016.11.032 ◽

2017 ◽

Vol 104 ◽

pp. 161-172 ◽

Cited By ~ 13

Author(s):

Markus Schmid ◽

Sandra Pröls ◽

Daniel M. Kainz ◽

Felicia Hammann ◽

Uwe Grupa

Keyword(s):

Whey Protein ◽

Molecular Interaction ◽

Whey Protein Isolate ◽

Protein Isolate ◽

Thermally Induced

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Whey Protein Isolate Microgel Properties Tuned by Crosslinking with Organic Acids to Achieve Stabilization of Pickering Emulsions

Foods ◽

10.3390/foods10061296 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1296

Author(s):

Jéssica Thaís do Prado Silva ◽

João Vitor Munari Benetti ◽

Taís Téo de Barros Alexandrino ◽

Odilio Benedito Garrido Assis ◽

Jolet de Ruiter ◽

...

Keyword(s):

Contact Angle ◽

Organic Acids ◽

Whey Protein ◽

Physical Stability ◽

Whey Protein Isolate ◽

Protein Isolate ◽

Pickering Emulsions ◽

Food Grade ◽

Oil Water ◽

Coffee Oil

Whey protein isolate (WPI) can be used effectively to produce food-grade particles for stabilizing Pickering emulsions. In the present study, crosslinking of WPI microgels using organic acids (tannic and citric acids) is proposed to improve their functionality in emulsions containing roasted coffee oil. It was demonstrated that crosslinking of WPI by organic acids reduces the microgels’ size from ≈1850 nm to 185 nm and increases their contact angle compared to conventional WPI microgels, achieving values as high as 60°. This led to the higher physical stability of Pickering emulsions: the higher contact angle and smaller particle size of acid-crosslinked microgels contribute to the formation of a thinner layer of particles on the oil/water (O/W) interface that is located mostly in the water phase, thus forming an effective barrier against droplet coalescence. Particularly, emulsions stabilized by tannic acid-crosslinked WPI microgels presented neither creaming nor sedimentation up to 7 days of storage. The present work demonstrates that the functionality of these crosslinked WPI microgels can be tweaked considerably, which is an asset compared to other food-grade particles that mostly need to be used as such to comply with the clean-label policy. In addition, the applications of these particles for an emulsion are much more diverse as of the starting material.

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