Response surface and contour plots for the effect of independent variables on total phenolics from peach extracts.

<p>Panel (A) power and temperature. Panel (B) time and temperature. Panel (C) time and power.</p

The effect of ultrasound frequency on % DPPH.

<p>The effect of ultrasound frequency on % DPPH.</p

Results of ANOVA and the regression coefficients.

<p>Results of ANOVA and the regression coefficients.</p

SEM images peach samples.

<p>Panel (A) a non-treated (B) a sample after solvent extraction. Panel (C) a sample after ultrasonic treatment sample.</p

Experimental values and solvent extraction of TP(mg/100 g gallic acid) and DPPH (%) obtained for peach extracts.

<p>Experimental values and solvent extraction of TP(mg/100 g gallic acid) and DPPH (%) obtained for peach extracts.</p

The effect of ultrasound frequency on total phenolic content.

<p>The effect of ultrasound frequency on total phenolic content.</p

Settings of variables for the experimental design.

<p>Settings of variables for the experimental design.</p

Response surface and contour plots for the effect of independent variables on % of DPPH from peach extracts.

<p>Panel (A) power and temperature. Panel (B) time and temperature. Panel (C) time and power.</p

FTIR spectra.

<p>Panel (a) Samples of pumpkin. Panel (b) samples of peach. Line (1) was non-processed, (2) was solvent extracted and (3) was ultrasonically processed</p

Response surface and contour plots for the effect of independent variables on total phenolics from pumpkin extracts.

<p>Panel (A) power and temperature. Panel (B) time and temperature. Panel (C) time and power.</p