Enhanced Lycopene Extraction from Gac (<italic>Momordica cochinchinensis</italic> Spreng.) by the <italic>Z</italic>‐Isomerization Induced with Microwave Irradiation Pre‐Treatment.

This study aims to improve the efficiency of lycopene extraction from gac (<italic>Momordica cochinchinensis</italic> Spreng.) by the <italic>Z</italic>‐isomerization induced with microwave irradiation pre‐treatment. Although 93.6% of lycopene exist as all‐<italic>E</italic>‐isomers in dried gac aril, the total <italic>Z</italic>‐isomer content reaches 35.6 and 58.5% by microwave irradiation at 900 W for 40 s and at 1050 W for 60 s, respectively. The 35.6 and 58.5% <italic>Z</italic>‐isomerization treatment improves lycopene content of extract (by 6.0 or 8.5 times for press extraction, 7.8 or 13.5 times for ethanol extraction, and 4.5 or 6.1 times for supercritical CO₂ (SC‐CO₂)extraction, respectively) compared with no treatment. In addition, the extracts containes high amounts of lycopene <italic>Z</italic>‐isomers, which have higher bioavailability and antioxidant capacity than (all‐<italic>E</italic>)‐lycopene. <italic>Practical Applications</italic>: This study clearly shows that lycopene recovery by press, organic solvent, and SC‐CO₂ extraction from dried gac aril improved by the increase in the <italic>Z</italic>‐isomer content. It indicates that the <italic>Z</italic>‐isomers are more soluble in oil, organic solvent, and SC‐CO₂ than the all‐<italic>E</italic>‐isomer. Moreover, the thermal <italic>Z</italic>‐isomerization pre‐treatment increases the content of lycopene <italic>Z</italic>‐isomers in the extract. Therefore, this procedure is important not only for improving the productivity of lycopene, but also for providing a highly functionalized extract. The effect of the <italic>Z</italic>‐isomerization, induced by microwave irradiation pre‐treatment of gac (<italic>Momordica cochinchinensis</italic> Spreng.) aril, on the lycopene recovery and lycopene content of the extracts obtained using press, ethanol, and SC‐CO₂ extractions is investigated. For all extraction methods, as the content of <italic>Z</italic>‐isomers in the raw material increases, the recovery and lycopene content of gac extracts improve. [ABSTRACT FROM AUTHOR]