In FDG, eleven soluble phenolic compounds were identified.
With the exception of syringic acid, all phenolic compounds
observed in fresh guava fruit were identified in FDG in addition
to quercetin and benzoic acid. In ODG, thirteen soluble phenolic
compounds were identified; the same eleven phenolics identified
in FDG plus syringic and rosmarinic acids. Recently identified
in FDG plus syringic and rosmarinic acids. Recently, Alves and
Perrone (2015) reported nine phenolic compounds in guava powder obtained by oven drying under the same conditions employed
in the present study. With the exception of myricetin, quercetin
and benzoic, syringic and rosmarinic acids, all phenolic compounds
observed in ODG were identified by Alves and Perrone (2015).
However, these authors identified ferulic acid, although in low contents (0.1 mg/100 g), which was investigated but not identified in
the present study (Table 2). The identification of a higher diversity
of phenolic compounds in guava powders than in the fresh fruit
may be explained by their relative concentration caused by water
loss in both dehydration processes.