Effect of ultrasound treatments of tomato pulp on microstructure and lycopene in vitro bioaccessibility.

Monica Anese, Giorgio Mirolo, Paola Beraldo, Giovanna Lippe

Dipartimento di Scienze degli Alimenti, University of Udine, Via Sondrio 2/A, 33100 Udine, Italy. monica.anese@uniud.it

Food chemistry 2013 Jan 15

filter terms:

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. Copyright © 2012 Elsevier Ltd. All rights reserved.

Citation

Monica Anese, Giorgio Mirolo, Paola Beraldo, Giovanna Lippe. Effect of ultrasound treatments of tomato pulp on microstructure and lycopene in vitro bioaccessibility. Food chemistry. 2013 Jan 15;136(2):458-63