title: Effect of ultrasound treatments of tomato pulp on microstructure and lycopene in vitro bioaccessibility.
abstract: The influence of ultrasound treatments of tomato pulp on microstructure and lycopene in vitro bioaccessibility was investigated. To this purpose, samples were subjected to ultrasound at a frequency and amplitude of 24 kHz and 100 μm, respectively, for increasing lengths of time. Results showed that ultrasound was responsible for loss of tomato cell integrity, as well as a decrease in the degree of pectin esterification. In contrast, rheological measurements showed that ultrasonically treated tomato pulp had greater gel-like properties than an untreated sample. It was inferred that ultrasound promoted the formation of a new network due to hydrogen bonding and hydrophobic interactions among the de-esterified pectin molecules. Such a reinforcement of the tomato pulp structure resulted in a decrease in lycopene in vitro bioaccessibility of the ultrasonically treated tomato pulp, probably due to the fact that the presence of a stronger network may make lycopene less available to the digestion process.
authors.affiliation: Dipartimento di Scienze degli Alimenti, University of Udine, Via Sondrio 2/A, 33100 Udine, Italy. monica.anese@uniud.it
authors.forename: Monica
authors.initials: M
authors.lastname: Anese
authors.forename: Giorgio
authors.initials: G
authors.lastname: Mirolo
authors.forename: Paola
authors.initials: P
authors.lastname: Beraldo
authors.forename: Giovanna
authors.initials: G
authors.lastname: Lippe
mesh_terms: D001682:Biological Availability; D002338:Carotenoids / Q000737:chemistry* / Q000378:metabolism; D004063:Digestion; D005511:Food Handling / Q000379:methods*; D006801:Humans; D000077276:Lycopene; D018551:Solanum lycopersicum / Q000737:chemistry* / Q000378:metabolism; D008954:Models, Biological; D014465:Ultrasonics / Q000379:methods*
chemical_list: D002338:Carotenoids; D000077276:Lycopene