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 (X-1), olive oil addition (X-2), gastric pH (X-3), gastric digestion time (X-4), pepsin concentration (X-5), intestinal pH (X-6), pancreatin concentration (X-7), bile salts concentration (X-8), colipase addition (X-9), intestinal digestion time (X-10), and intestinal digestion speed (X-11). 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 X-3, X-6, X-7, and X-11, 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.