Detection of key factors affecting lycopene in vitro accessibility.

On the basis of a Plackett-Burman experimental design for a resolution IV level obtained via a foldover strategy, the effect of 11 factors on lycopene in vitro accessibility was investigated. The selected factors were thermal treatment (X1), olive oil addition (X2), gastric pH (X3), gastric digestion time (X4), pepsin concentration (X5), intestinal pH (X6), pancreatin concentration (X7), bile salts concentration (X8), colipase addition (X9), intestinal digestion time (X10), and intestinal digestion speed (X11). Tomato passata was used as a natural source of lycopene. Samples were collected after gastric and intestinal digestion, and from the micellar phase, to quantify the (all-E)-lycopene and its (Z)-isomers by HPLC. Except for X3, X6, X7, and X11, the other factors studied explained lycopene in vitro accessibility, mainly regarding intestinal digestion, with R(2) values ≥ 0.60. Our results showed that the accessibility of lycopene is influenced by the conditions applied during in vitro intestinal digestion.