Analysis of Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy, non-protein nitrogen content and amino acid content revealed slight modification in the protein advance structure in terms of pretreatment, however, the main peptide chain and amino acid composition were not altered. There was an increase in free sulfhydryl and a decrease in disulfide bond contents in all the treatments except EVH.

Surface hydrophobicity of EVU extracted proteins increased compared to the other treatments. EVU enhanced the functionality of extracted proteins in terms of solubility, foam capacity and stability, and emulsion capacity and stability.

EVU pretreatment together with alkaline extraction resulted in the highest protein recovery yield of 80.95% with a purification factor of 8.5. Four extraction pathways: ethanol, Viscozyme, ultrasound (EVU) water, Viscozyme, ultrasound (WVU) ethanol, water, ultrasound (EWU) and ethanol, Viscozyme, heat (EVH) were employed. 2695-2707 ISSN: 2193-4126 Subject: Fourier transform infrared spectroscopy, amino acid composition, biorefining, byproducts, disulfide bonds, emulsions, ethanol, galacturonic acid, heat, hydrophobicity, nonprotein nitrogen, peptides, polyphenols, proteins, solubility, tea, ultrasonic treatment, ultrasonics, ultraviolet-visible spectroscopy Abstract: The effect of integrating ultrasonic pretreatment with ethanol and Viscozyme in the alkaline extraction of protein from tea residue and the generation of possible by-products such as polyphenols and galacturonic acid was assessed.

Integration of ultrasonic treatment in biorefinery of tea residue: protein structural characteristics and functionality, and the generation of by-products Author: Ishmael Ayim, Haile Ma, Evans Adingba Alenyorege, Zeshan Ali, Prince Ofori Donkor, Cunshan Zhou Source: Journal of food measurement & characterization 2018 v.12 no.4 pp.

Wvu free endnote