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Quality parameters of açai juice processed with ultrasound-assisted, ozone and the combined methods were analyzed in this work. Two ultrasound energy densities (350 and 700 J·mL −1 ) and two ozonization times (5 and 10 min with 1.5 ppm) were analyzed for pure açai juice and 8 different treatments (2 2 complete factorial). To evaluate the quality parameters of the juice, physical-chemical analyzes such as pH, titratable acidity, cloud value, non-enzymatic browning, rheology, antioxidant activity (DPPH and ABTS), phenolic compounds, anthocyanins, enzymatic activity (peroxidase and polyphenol oxidase) and microbial counts (mesophilic bacteria, molds and yeasts) were conducted. The treatments with ozone were better for microbial inactivation and the ultrasound for enzymatic inactivation. In general, the use of non-thermal methods can be a good alternative for the processing of açai juice. [ABSTRACT FROM AUTHOR]

[Display omitted] • An efficient ginseng residue oligosaccharide decolorization method was developed. • Three decolorization methods were systematically compared. • Ultrasound-assisted decolorization greatly shortened the decolorization time. • The GRO structure did not change significantly before and after decolorization. An efficient decolorization method for ginseng residue oligosaccharides (GROs) using ultrasound-assisted D392 macroporous resin was developed. The decolorization effects and color differences of activated carbon adsorption, hydrogen peroxide oxidation, and resin adsorption were evaluated. The optimal conditions of the three decolorization methods for static, dynamic, ultrasound-assisted resin adsorption were compared. The results showed that ultrasound-assisted decolorization had the best decolorization effect of greatly decreasing the decolorization time to 80 min. Color difference analysis revealed the process of pigment removal during GRO decolorization. The UV–visible full-wavelength scan showed that most pigments were removed after decolorization. The characterizations by the Fourier-transform infrared spectroscopy and X-ray diffraction analysis showed that the chemical structure and crystallinity of the GROs did not change upon decolorization. In addition, the molecular weight distribution did not change significantly. This research contributes to further exploration of the structures and functions of GROs. [ABSTRACT FROM AUTHOR]

Highlights: [•] UAE is an effective method for annatto colour extraction in compare to conventional extraction methods. [•] In the optimum conditions, the absorbance value and the extraction yield were obtained 0.865% and 6.35%, respectively. [•] ASE extracted by UAE showed more antioxidant activity than ASE extracted by conventional method. [Copyright &y& Elsevier]