Cell wall phenolics of white and green asparagus

Abstract

Cinnamic acids influence physical and textural attributes of plant foods as they play an important role in lignification and cross-linking of cell-wall polymers. Several trans-cinnamic acids have been detected in asparagus cell wall (CW), and, of these, amounts of ferulic acid (FA) and its dehydrodimers have been found to increase significantly during post-harvest storage. The distribution of these compounds along the different sections of white and green spears, as well as their modifications during postharvest storage, has been investigated. It has been observed that the cell walls from the apical, middle and lower sections of the green spears contain equivalent amounts of FA derivatives (about 400 µg g−1 CW), while these compounds are mainly located in the middle (681 µg g−1 CW) and lower section (975 µg g−1 CW) of the white ones. During asparagus post-harvest storage a general increase of FA monomers and dimers took place that affected every section of both green and white spears. Major changes occurred in the middle and lower sections of the white asparagus, where the amounts of ferulic derivatives increased to 1700 and 1678 µg g−1 CW after storage. A similar but less pronounced trend was observed for the green spears.