MDA content was assayed using the method of Pongprasert et al. [23] with a slight modification. Pear peel (5 g)
was homogenized in 25 ml 5% (w/v) trichloroacetic acid (TCA). The mixture was centrifuged for 15 min at
4000 × g. To 1.5 ml of the supernatant was added 2.5 ml 0.5% (w/v) thiobarbituric acid (TBA) in 15% TCA.
The reaction solution was held for 20 min in a boiling water bath, cooled quickly, and centrifuged at 12,000 × g
for 10 min to clarify the solution. Absorbance was measured at 532 nm and corrected for non-specific turbidity
by subtracting the absorbance at 600 nm, calculated with an extinction coefficient of 1.55 nmol/(l.m), and expressed
as nmol/g FW.