Production of ()-Lycopene-Rich Tomato Concentrate: A Natural Catalyst-Utilized and Oil-Based Study for Practical Applications.

Since lycopene -isomers exhibit greater bioavailability and biological activity than the naturally occurring all--isomer, efficient manufacturing methods for ()-lycopene-rich materials are urgently needed. Herein, a method was developed for -isomerization of (all-)-lycopene in tomato oleoresin using heat treatment and a natural catalyst, viz. allyl isothiocyanate (AITC). For practical application of this isomerization technology, no organic solvents were used, and instead, oils and fats were used as the reaction medium. The -isomerization of (all-)-lycopene was promoted by heating (>120 °C) even when oil and fat media were used. Allyl isothiocyanate enhanced thermal -isomerization and improved the (5)-lycopene content, which shows higher biological activity compared to the other -isomers. The thermal isomerization efficiency with AITC was further improved by using certain vegetable oils such as argan and olive oils. In addition, the storage stability of ()-lycopene-rich tomato concentrates dispersed in olive oil was evaluated. The total -isomer ratio and lycopene concentration decreased with longer storage periods, and it was revealed that (5)-lycopene showed excellent storage stability among the mono--isomers.