Passion fruit powder and the pectin samples were observed using scanning electron microscopy (S-3400N,
Hitachi, Japan). The SEM was used to elucidate morphological changes of samples which were extracted by acidic
extraction method. Dry pectin sample was dried using microwave and wet pectin sample was the crude pectin. The
morphological of wet pectin sample and dry pectin sample were analyzed to obtain the microwave heating effect on
pectin structure. The preparation of pectin samples for SEM include mounting the pectin samples on the aluminum
studs, pectin samples coating with gold in vacuum and observing the pectin samples by SEM.