procyanidin and total anthocyanin while heating at
higher temperature for more than 8 hours results in
considerable loss. Hence, vacuum evaporation which
the lower heating temperature was used and lower
oxygen seemed to be appropriated for preserving total
phenolic and anthocyanin. Adams (1973) reported that
heating under aerobic condition (oxygen headspace)
accelerate anthocyanin degradation. It also caused
anthocyanin structure from cyanidin-3-glucoside
to cyanidin which was very labile or cyanidin-3-rutinoside to cyanidin-3-glucoside.
The use of pectinase enzyme significantly
increased total phenolic content (Table 6). Pectinase
enzyme included pectin methyl esterase and
depolymerizing enzyme. Since mangosteen is
composed of oligomeric procyanidin bonded readily
to cell-wall polysaccharides through hydrogenbonding and/or hydrophobic interactions (Renard,
Baron, Guyot and Drilleau, 2001), pectinase enzyme
can degrade the cell-wall and vacuolar membrane and
increase the extraction of procyanidin (Oszmiański et
al., 2011). The result of Landbo and Meyer (2004)
and Landbo et al.(2007) showed that the increased
pectinase enzyme dosage and the maceration time
and temperature had significantly positive effects
on the juice yield and total phenol yield in the black
currant juice and elderberry juice since the pectinase
enzyme addition can breaking down the pectin in the
plant cell walls and in the middle lamellae between
the plant cells and releasing possible cell wall sited
phenolics.
The use of pectinase enzyme tentatively decreased
anthocyanin content (Table 6). These result agreed
with those of Versari et al. (1997) who suggested
that some pectinase enzyme produced glucosidase
activity which has a hydrolytic activity to degrade
anthocyanin pigment. Jiang et al. (1990) also
reported the 20% loss of raspberry anthocyanin after
treated with pectinase enzyme was because some
pectinase enzyme contained a glucosidase which can
hydrolyzed the β1–2 glucosidic bonds of cyanidin-3-sophoroside and cyanidin-3-glucosylrutinoside
into cyanidin-3-glucoside and cyanidin-3-rutinoside,
which in turn resulted in decreasing the anthocyanin
stability.