Solids were stable and did not show visible signs or changes in their spectra after being kept at room temperature for over 60 days. The absorbance at the maximum absorbance wavelength remained unmodified.

Macromolecular oxidation was detected in proteins by the colorimetric measurement of Advanced Oxidation Protein Products (AOPP) and in lipids by the colorimetric quantification of malondialdehyde (MDA). Standard curves were run with chloramine-T and 1,1,3,3 tetraethoxypropane (TEP) for AOPP and MDA methods, respectively [29], [30], [31]. Values were normalized to initial protein content in samples, measured with Bradford reagent [32]. The standard deviation of at least six measures was calculated and p-value < 0.05 were considered significant.

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