2.7. Total extractable polyphenol level determination
The total extractable polyphenols were determined by the
Folin–Ciocalteu method, using a standard curve prepared with
galic acid (Sigma Aldrich, Saint Louis, USA) as a reference, according
to the methodology described by Larrauri, Rupérez, and Saura-
Calixto (1997). The determination of total extractable polyphenols
before in vitro simulated gastrointestinal digestion of the cashew
apple juice and cashew apple fibre was performed according to
the methodology described by Larrauri et al. (1997), by reading
the extracts in a spectrophotometer (Shimadzu, model UV-1800)
at 700 nm. For the determination of total extractable polyphenols
after simulated gastrointestinal digestion in vitro the dialysate
was analysed using the same methodology described for the determination
of total extractable polyphenols before gastrointestinal
digestion. The results were expressed in mg of galic acid equivalent
(GAE) 100 g1. The bioaccessible percentage was calculated
according to Briones-Labarca et al. (2011) (Eq. (3)).