Lycopene is a red pigment from red tomatoes (Solanum lycopersicum) . It is a carotenoid, located deeply inside the chromoplast of tomatoes and attached to the membranes. Cooking dissociates the food matrix and lycopene is released .
Raw tomato contains 0.8 to 3.7 mg/100gm of lycopene
Whereas, cooked tomato paste contain 32 to 94mg/100gm of lycopene .
When tomatoes are consumed raw, lycopene is poorly absorbed. But, when the tomatoes are cooked and consumed with little amount of fat such as extra virgin olive oil, the bioavailability of lycopene is greatly improved , antioxidant effect, Z-isomer (which is the active lycopene), total carotenoids, alpha-carotene and beta-carotene levels are increased by cooking tomatoes with oil  .
Raw onion puree with extra virgin olive oil when mixed with tomatoes and cooked increased the Z-isomer of lycopene [5,6]. This might be the reason, Mediterranean and Indian cooking uses onion, garlic and tomato puree with some fat substance such as olive oil or ghee .
Tomato skin also contains high amount of lycopene and therefore, peeling of tomato skin causes loss of lycopene . Tomato puree also improves heat stability of edible oils .
Several health benefits of lycopene:
- Antioxidant 
- Anti-inflammatory 
- Anti-cancer 
- Anti-ageing 
- Anti-obesity 
- Anti-diabetic 
- Heart health 
- Reduces total cholesterol and LDL cholesterol 
- Also good for bone health, gingivitis, sunburn and mental health .
- Perveen R, Suleria HAR, Anjum FM, et al. (2015) Tomato (Solanum lycopersicum) Carotenoids and Lycopenes Chemistry; Metabolism, Absorption, Nutrition, and Allied Health Claims—A Comprehensive Review. Critical Reviews in Food Science and Nutrition 55: 919-929.
- Lowe GM, Graham DL, Young AJ (2018) Lycopene: Chemistry, Metabolism, and Bioavailability. Lycopene and Tomatoes in Human Nutrition and Health: CRC Press. pp. 1-20.
- de Alvarenga JFR, Lozano-Castellón J, Martínez-Huélamo M, et al. (2018) Cooking Practice and the Matrix Effect on the Health Properties of Mediterranean Diet: A Study in Tomato Sauce. Advances in Plant Phenolics: From Chemistry to Human Health: American Chemical Society. pp. 305-314.
- Vallverdú-Queralt A, Regueiro J, De Alvarenga JFR, et al. (2015) Carotenoid Profile of Tomato Sauces: Effect of Cooking Time and Content of Extra Virgin Olive Oil. International Journal of Molecular Sciences 16: 9588-9599.
- Yu J, Gleize B, Zhang L, et al. (2019) Heating tomato puree in the presence of lipids and onion: The impact of onion on lycopene isomerization. Food Chemistry 296: 9-16.
- Arranz S, Martínez-Huélamo M, Vallverdu-Queralt A, et al. (2015) Influence of olive oil on carotenoid absorption from tomato juice and effects on postprandial lipemia. Food Chemistry 168: 203-210.
- Rinaldi de Alvarenga JF, Tran C, Hurtado-Barroso S, et al. (2017) Home cooking and ingredient synergism improve lycopene isomer production in Sofrito. Food Research International 99: 851-861.
- Martínez-Hernández GB, Boluda-Aguilar M, Taboada-Rodríguez A, et al. (2016) Processing, Packaging, and Storage of Tomato Products: Influence on the Lycopene Content. Food Engineering Reviews 8: 52-75.
- Kaur G, Sandal A, Dhillon NS (2017) Lycopene and human health-A review. Agricultural Reviews 38: 282-289.
- Landrier J-F, Tourniaire F, Fenni S, et al. (2017) Tomatoes and lycopene : inflammatory modulator effects. Tomatoes and lycopene in human nutrition and health, preventing chronic diseases: CRC Press, Boca Raton. Florida (USA). pp. np.