Interfacial Properties of β-Lactoglobulin at the Oil/Water Interface: Influence of Starch Conversion Products with Varying Dextrose Equivalents

AbstractIn spray dried emulsions, frequently milk proteins are used as interfacial active components and starch conversion products are added as matrix material at high concentrations. To characterize interfacial properties at the oil/water interface by commonly applied methods, low protein, and carbohydrate concentrations from 1 to 2% are usually analyzed. The impact of a higher concentration of starch conversion products was not investigated so far. Therefore, the formation and rheological properties of β-lactoglobulin (β-LG) stabilized films at the oil/water interface were investigated via short and long-time adsorption behavior using pendant drop tensiometry as well as dilatational and interfacial shear rheology. Suitability of the applied methods to the chosen samples with higher concentrations >1–2% was verified by calculation of selected key numbers like capillary number and by detailed reviewing of the results which is summarized further on as key indicators. It is hypothesized, that the increase in concentration via presence of starch conversion products will delay interfacial stabilization as a result of increased bulk viscosity with decreasing degree of degradation (dextrose equivalent) of the starch. Furthermore, this increase in concentration leads to more stable interfacial films due to thermodynamic incompatibility effects between protein and starch conversion products which results in increases of local protein concentration. Key indicators proved a general suitability of applied methods for the evaluation of the investigated samples. Moreover, results showed an increase in interfacial film stability and elastic properties alongside a decreased interfacial tension if starch conversion products were present in a high concentration.

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Effect of iron chelates on oil–water interface, stabilized by milk proteins: The role of phosphate groups and pH. Prediction of iron transfer from aqueous phase toward fat globule surface by changes of interfacial properties

Food Hydrocolloids ◽

10.1016/j.foodhyd.2009.11.002 ◽

2010 ◽

Vol 24 (4) ◽

pp. 364-373 ◽

Cited By ~ 8

Author(s):

Tatiana Guzun-Cojocaru ◽

Philippe Cayot ◽

Camille Loupiac ◽

Eliane Cases

Keyword(s):

Aqueous Phase ◽

Milk Proteins ◽

Interfacial Properties ◽

Water Interface ◽

Iron Chelates ◽

Iron Transfer ◽

Fat Globule ◽

Oil Water ◽

Phosphate Groups

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Adsorption Kinetics and Rheological Interfacial Properties of Plant Proteins at the Oil−Water Interface

Biomacromolecules ◽

10.1021/bm049739h ◽

2004 ◽

Vol 5 (6) ◽

pp. 2088-2093 ◽

Cited By ~ 36

Author(s):

V. Ducel ◽

J. Richard ◽

Y. Popineau ◽

F. Boury

Keyword(s):

Adsorption Kinetics ◽

Interfacial Properties ◽

Water Interface ◽

Plant Proteins ◽

Oil Water

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Evaluation of interfacial properties of the silane blend sized glass fiber–epoxy composite by the microdroplet test

Journal of Composite Materials ◽

10.1177/0021998316661620 ◽

2016 ◽

Vol 51 (11) ◽

pp. 1573-1581 ◽

Cited By ~ 1

Author(s):

Somayeh Safi ◽

Ali Zadhoush ◽

Mahmood Masoomi

Keyword(s):

Glass Fiber ◽

Epoxy Matrix ◽

Interfacial Adhesion ◽

Matrix Material ◽

Interfacial Properties ◽

Material System ◽

Critical Energy Release Rate ◽

Adhesion Properties ◽

The Impact ◽

Scanning Electron

The performance of a composite material system depends critically on the interfacial characteristics of the reinforcement and the matrix material. In this study, the interfacial adhesion was tailored by the creation of textures on the glass fiber surface using inorganic-organic silane blends. A single-fiber microdroplet test was conducted to assess the interfacial properties between the textured glass surface and an epoxy matrix. The load–displacement curves from microdroplet tests were analyzed. The stress-based and energy-based micromechanic models of interfacial debonding and corresponding adhesional parameters (apparent and ultimate interfacial shear strength, friction stress, critical energy release rate, work of adhesion, and adhesional pressure) were applied for theoretical calculations. The results showed a clear trend for the impact of different silane blends on the interfacial properties. The specimens containing 75:25 and 50:50 of inorganic–organic silane blends show the most effective improvement in the interfacial adhesion properties between glass fiber and epoxy resin. Scanning electron microscopy was used to visualize the failure surface of the specimen after the microdroplet test. The scanning electron microscopic images indicated that the failure in the blend sized treated glass fiber–epoxy matrix specimen runs predominantly along the interphase and combines both cohesive failure in resin (the presence of some resin fragments) and adhesive failure (some bare fiber surfaces can be seen).

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