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Fabrication of soy protein–polyphenol covalent complex nanoparticles with improved wettability to stabilize high‐oil‐phase curcumin emulsions

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Journal of The Science of Food and Agriculture
Authors:
Jingjing Xu
Jingjing Xu
Jingjing Xu
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Fuyun Ji at Anqing Normal University
Fuyun Ji
Shuizhong Luo
Shuizhong Luo
Shuizhong Luo
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Shaotong Jiang at Hefei University of Technology
Shaotong Jiang
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Abstract and Figures

BACKGROUND Recent studies have shown that the wettability of protein‐based emulsifiers is critical for emulsion stability. However, few studies have been conducted to investigate the effects of varying epigallocatechin gallate (EGCG) concentrations on the wettability of protein‐based emulsifiers. Additionally, limited studies have examined the effectiveness of soy protein–EGCG covalent complex nanoparticles with improved wettability as emulsifiers for stabilizing high‐oil‐phase (≥ 30%) curcumin emulsions. RESULTS Soy protein isolate (SPI)–EGCG complex nanoparticles (SPIEn) with improved wettability were fabricated to stabilize high‐oil‐phase curcumin emulsions. The results showed that EGCG forms covalent bonds with SPI, which changes its secondary structure, enhances its surface charge, and improves its wettability. Moreover, SPIEn with 2.0 g L ⁻¹ EGCG (SPIEn‐2.0) exhibited a better three‐phase contact angle (56.8 ± 0.3o) and zeta potential (−27 mV) than SPI. SPIEn‐2.0 also facilitated the development of curcumin emulsion gels at an oil volume fraction of 0.5. Specifically, the enhanced network between droplets as a result of the packing effects and SPIEn‐2.0 with inherent antioxidant function was more effective at inhibiting curcumin degradation during long‐term storage and ultraviolet light exposure. CONCLUSION The results of the present study indicate that SPIEn with 2.0 g L ⁻¹ EGCG (SPIEn‐2.0) comprises the optimum conditions for fabricating emulsifiers with improved wettability. Additionally, SPIEn‐0.2 can improve the physicochemical stability of high‐oil‐phase curcumin emulsions, suggesting a novel strategy to design and fabricate high‐oil‐phase emulsion for encapsulating bioactive compounds. © 2024 Society of Chemical Industry.
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Research Article
Received: 28 March 2024 Revised: 30 May 2024 Published online in Wiley Online Library:
(wileyonlinelibrary.com) DOI 10.1002/jsfa.13672
Fabrication of soy protein–polyphenol
covalent complex nanoparticles with
improved wettability to stabilize high-
oil-phase curcumin emulsions
Jingjing Xu,a,b Fuyun Ji,aShuizhong Luo,aShaotong Jiang,aZhenyu Yu,c
Aiqian Yeband Zhi Zhenga
*
Abstract
BACKGROUND: Recent studies have shown that the wettability of protein-based emulsifiers is critical for emulsion stability.
However, few studies have been conducted to investigate the effects of varying epigallocatechin gallate (EGCG) concentrations
on the wettability of protein-based emulsifiers. Additionally, limited studies have examined the effectiveness of soy protein–
EGCG covalent complex nanoparticles with improved wettability as emulsifiers for stabilizing high-oil-phase (≥30%) curcumin
emulsions.
RESULTS: Soy protein isolate (SPI)–EGCG complex nanoparticles (SPIE
n
) with improved wettability were fabricated to stabilize
high-oil-phase curcumin emulsions. The results showed that EGCG forms covalent bonds with SPI, which changes its secondary
structure, enhances its surface charge, and improves its wettability. Moreover, SPIE
n
with 2.0 g L
−1
EGCG (SPIE
n-2.0
) exhibited a
better three-phase contact angle (56.8 ±0.3
o
) and zeta potential (−27 mV) than SPI. SPIE
n-2.0
also facilitated the development
of curcumin emulsion gels at an oil volume fraction of 0.5. Specifically, the enhanced network between droplets as a result of
the packing effects and SPIE
n-2.0
with inherent antioxidant function was more effective at inhibiting curcumin degradation dur-
ing long-term storage and ultraviolet light exposure.
CONCLUSION: The results of the present study indicate that SPIE
n
with 2.0 g L
−1
EGCG (SPIE
n-2.0
) comprises the optimum con-
ditions for fabricating emulsifiers with improved wettability. Additionally, SPIE
n-0.2
can improve the physicochemical stability
of high-oil-phase curcumin emulsions, suggesting a novel strategy to design and fabricate high-oil-phase emulsion for encap-
sulating bioactive compounds.
© 2024 Society of Chemical Industry.
Supporting information may be found in the online version of this article.
Keywords: soy protein isolate; EGCG; covalent bonds; wettability; curcumin emulsion
INTRODUCTION
Emulsion-based delivery systems are widely used in the food and
pharmaceutical fields for encapsulating, protecting and transport-
ing lipophilic bioactive components, including carotenoids and
flavonoids.
1
Previous studies have demonstrated that the stability
and bioaccessibility of lipophilic bioactive components can be
promoted when they are incorporated into oil-in-water (O/W)
emulsions.
2-4
Protein-based nanoparticles are generally recog-
nized as effective emulsifiers to stabilize O/W emulsions.
2,3,5,6
Soy protein, the major storage protein in soybeans, has gained
significant attention as a popular emulsifier because of its excep-
tional nutritional content, excellent emulsifying properties and
good biocompatibility.
7
More importantly, soy protein is abun-
dant and derived from natural sources.
8
However, it is difficult
for the emulsion prepared by a protein as an emulsifier to remain
stable under various environmental stresses, such as pH, ionic
strength and temperature, because its molecular conformation
is susceptible to certain processing and storage conditions.
9
To address these drawbacks, protein–polyphenol covalent con-
jugates have been widely used as emulsifiers to improve the phys-
icochemical stability of emulsions under different food processing
*Correspondence to: Z Zheng, School of Food and Biological Engineering, The
Key Laboratory for Agricultural Products Processing of Anhui Province, Hefei
University of Technology, Hefei 230009, China. E-mail: zhengzhi@hfut.edu.cn
aSchool of Food and Biological Engineering, The Key Laboratory for Agricultural
Products Processing of Anhui Province, Hefei University of Technology, Hefei,
China
bRiddet Institute, Massey University, Palmerston North, New Zealand
cSchool of Tea and Food Science & Technology, Anhui Agricultural University,
Hefei, China
J Sci Food Agric 2024 www.soci.org © 2024 Society of Chemical Industry.
1
ResearchGate has not been able to resolve any citations for this publication.
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