Evaluation of the properties of double emulsions (W/O/W) stabilized with whey protein isolate-inulin conjugate

Abstract:
Background and objectives: The glycation of Proteins usually considered as the first step of the Maillard reaction. Studies have shown that the functional properties of whey protein isolate have been significantly improved by conjugation by carbohydrates through the Millard process. Therefore,the aim of this research is to stibilize double emulsions (W/O/W) with whey protein isolate -inulin conjugates.
Materials and methods: The conjugation variables were WPI to inulin ratios (1:1, 1:2, and 2:1w/w) and incubation temperatures (60 and 80°C) at 79% relative humidity for 24 h. In this study, we investigated the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS- PAGE) , Fourier transform infrared spectroscopy (FT-IR) and color of conjugates. The apparent viscosity, particle size and distribution, zeta potential and creaming of W/O/W emulsions were measured during storage time. Emulsions stabilized by conjugates produced by heating at 80°C had higher zeta potential than emulsions stabilized with conjugates produced by heating at 60°C on the first day of production. The W1/O/W2 emulsions stabilized by 1:2 ratio of whey protein isolate-inulin conjugate showed a higher zeta potential value on the first day and after 21 days of storage.
Results: The droplet size of W/O/W emulsions stabilized with conjugates produced at 80 ° C was less than the conjugates prepared at 60° C. The 2:1 and 1:2 weight ratios of whey protein isolate-inulin showed the maximum and minimum droplet size of emulsions during storage.
Conclusion: Generally, the results showed that whey protein isolate-inulin conjugates have a favorable ability to stabilize double emulsions, especially a weight ratio of 1:2, hence these emulsions can be used for the encapsulation of various bioactive compounds.
Abstract:
Background and objectives: The glycation of Proteins usually considered as the first step of the Maillard reaction. Studies have shown that the functional properties of whey protein isolate have been significantly improved by conjugation by carbohydrates through the Millard process. Therefore,the aim of this research is to stibilize double emulsions (W/O/W) with whey protein isolate -inulin conjugates.
Materials and methods: The conjugation variables were WPI to inulin ratios (1:1, 1:2, and 2:1w/w) and incubation temperatures (60 and 80°C) at 79% relative humidity for 24 h. In this study, we investigated the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS- PAGE) , Fourier transform infrared spectroscopy (FT-IR) and color of conjugates. The apparent viscosity, particle size and distribution, zeta potential and creaming of W/O/W emulsions were measured during storage time. Emulsions stabilized by conjugates produced by heating at 80°C had higher zeta potential than emulsions stabilized with conjugates produced by heating at 60°C on the first day of production. The W1/O/W2 emulsions stabilized by 1:2 ratio of whey protein isolate-inulin conjugate showed a higher zeta potential value on the first day and after 21 days of storage.
Results: The droplet size of W/O/W emulsions stabilized with conjugates produced at 80 ° C was less than the conjugates prepared at 60° C. The 2:1 and 1:2 weight ratios of whey protein isolate-inulin showed the maximum and minimum droplet size of emulsions during storage.
Conclusion: Generally, the results showed that whey protein isolate-inulin conjugates have a favorable ability to stabilize double emulsions, especially a weight ratio of 1:2, hence these emulsions can be used for the encapsulation of various bioactive compounds.