Characterization of Cell Wall Enzyme Activities, Pectin Composition, and Technological Criteria of Strawberry Cultivars (Fragaria×ananassaDuch)

Abstract

The effects of physical characteristics and cell wall enzymatic activities of several strawberry cultivars were investigated for possible industrial use. The enzymes study showed that the softest varieties had the highest pectin methylesterase (PME) and polygalacturonase (PG) activities. Differences in alcohol-insoluble pectin, water-soluble pectin, and parietal residue compositions were observed between Darsanga ("firm fruit") and Senga sengana ("soft fruit"). Finally, the study of pectin composition of Darsanga and Senga sengana indicated that the softest fruit had the highest water-soluble pectin content. The measurement of fruit PME activity permitted a preliminary screening of fruit maturity characteristics.

Enzyme infusion prior to thermal/high pressure processing of strawberries: Mechanistic insight into firmness evolution

“…Similar values were found by Duvetter et al (2005a) (DM = 79%), while Lefever et al (2004) reported somewhat lower values (DM = 67-75%). Pectin in strawberries that were infused with PME+Ca 2+ had a lower DM, indicating that PME had acted on the pectin.…”

Antisense inhibition of pectate lyase gene expression in strawberry fruit: Characteristics of fruits processed into jam

“…In the two independent lines analyzed, transgenic antipectate lyase fruits withstand better the cooking process resulting in an increased content of whole berries in jam. Content of whole berries after cooking in the presence of sugar is one of the most representative quality criteria of processed strawberry (Haffner, 2002;Lefever et al, 2004). The higher values of firmness observed in fresh transgenic fruits when compared with control were also maintained after being processed the fruits.…”

Antisense Down-Regulation of theFaPG1Gene Reveals an Unexpected Central Role for Polygalacturonase in Strawberry Fruit Softening

“…Contrary to these research findings, Villarreal et al (2008) recently found that PG activity increases in strawberry fruit during development and that total PG activity correlates positively with fruit softening. Similarly, Lefever et al (2004) found that softness in strawberry varieties correlated positively with PG activity in ripening fruits. At the molecular level, three ripening-related PG genes have been cloned.…”