Modifications in the methods to extract pectin from cv. “Pedro Sato” guavas during ripening

Abstract

Guava is a highly perishable fruit due to its intense metabolism during ripening, with a shelf life of up to five days at room temperature. The loss of firmness during ripening is caused by the activity of hydrolytic enzymes that promote dissolution of the pectin constituents of the cell wall. Although guava is considered to be rich in pectin, the amounts reported in the literature do not exceed 2.4%, a content indicating it is not responsible for the firmness of guava. The aim of this study was to extract pectin from the guava pulp during 7 days of ripening by two methods (ethanol and EDTA extraction) and suggest modifications in the methods by adding to the extraction residue, cellulase and pectinase to degrade the cell wall structure of the fruit and obtain larger amounts of pectin, which would imply the participation of pectin in the maintenance of fruit firmness. It was possible to infer there were no differences in the pectin levels extracted by the two methods, due to sugar contamination. As from the new stage in the execution by the two methods, the extraction was more efficient: 9.10% of pectin with EDTA and 7.63% with ethanol. The pectin contents found were higher than those mentioned in the literature, better explaining their responsibility in fruit firmness.

Produção, rendimento e caracterização físico-química de pectina a partir da entrecasca de melancia (Citrullus lanatus): otimização por experimento Box-Behnken

“…Outros açúcares neutros, como galactose e arabinose podem ser observados em cadeias laterais (FERNNDES et al, 2014). Vários são os usos da pectina, nos frutos os polímeros de pectina são os responsáveis por manter a firmeza dos frutos verde e maduros (SPILLER et al, 2018;ABREU et al, 2012), e nos processos industriais como por exemplo, pode ser utilizada na produção de minibactérias, na fabricação de gomas e balas de mascar, geleias, biofilmes e espessantes para sucos (LIMA et al, 2017;DA SILVA et al, 2014).…”