The relative lower absorbance of ester
group of pectin (1735 cm1) was found in fruits stored at 10 C
for 21 d as compared to 14 d storage, resulting in correspondingly
higher absorbance of carboxyl group (1400–1450 cm1) and carboxylate
group (1600–1650 cm1) of pectin in cell wall (Fig. 4A).