Sweet tea extract encapsulated by different wall material combinations with improved physicochemical properties and bioactivity stability

Abstract

Aim: To prepare sweet tea extract microcapsules (STEMs) via a spray-drying by applying different wall material formulations with maltodextrin (MD), inulin (IN), and gum arabic (GA). Methods: The microcapsules were characterised by yield, encapsulation efficiency (EE), particle size, sensory evaluation, morphology, attenuated total reflectance-Fourier transform infra-red spectroscopy and in vitro digestion studies. Results: The encapsulation improved the physicochemical properties and bioactivity stability of sweet tea extract (STE). MD5IN5 had the highest yield (56.33 ± 0.06% w/w) and the best EE (e.g. 88.84 ± 0.36% w/w of total flavonoids). MD9GA1 obtained the smallest particle size (642.13 ± 4.12 nm). MD9GA1 exhibited the highest retention of bioactive components, inhibition of α-glucosidase (96.85 ± 0.55%), α-amylase (57.58 ± 0.99%), angiotensin-converting enzyme (56.88 ± 2.20%), and the best antioxidant activity during in vitro gastrointestinal digestion. Conclusion: The encapsulation of STE can be an appropriate way for the valorisation of STE with improved properties.

Keywords:

• Sweet tea extract
• encapsulation
• wall material combinations
• spray-drying
• in vitro gastrointestinal digestion

Acknowledgements

Guangxi University – Advanced Instrument Equipment Sharing platform is gratefully acknowledged for help.

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability statement

All data generated or analysed during this study are included in this manuscript.

Additional information

Funding

This work was financially supported by the Project of Bama County for Talents in Science and Technology [Grant No. 20210048], the Natural Science Foundation of Guangxi [Grant No. 2022GXNSFAA035455], the Special Projects of China Central Government Guiding Local Science and Technology Development of Guangxi [Grant No. ZY21195013], and the National Natural Science Foundation of China [Grant Nos. U21A20271, 31201349].