Lycopene Degradation and Isomerization Kinetics during Thermal Processing of an Olive Oil/Tomato Emulsion

Abstract

The stability of lycopene in an olive oil/tomato emulsion during thermal processing (80-140 °C) was studied. Initially, the degradation of total lycopene (all-E plus Z-forms) occurred quickly at temperatures above 100 °C. However, a nonzero plateau value, depending on the processing temperature, was attained after longer treatment times. Besides degradation, the isomerization of total-Z-lycopene as well as the individual isomerization of all-E-, 5-Z-, 9-Z-, and 13-Z-lycopene was studied in detail. After prolonged heating, the isomer conversion reached a temperature-dependent equilibrium state. The degradation of total lycopene and the isomerization could be described by a fractional conversion model. The temperature dependency of the corresponding reaction rate constants was quantified by the Arrhenius equation. The activation energy of degradation was estimated to be 28 kJ/mol, and the activation energy of overall (all-E and total-Z) isomerization was estimated to be 52 kJ/mol.

Lycopene degradation, isomerization and in vitro bioaccessibility in high pressure homogenized tomato puree containing oil: Effect of additional thermal and high pressure processing

“…As stated before, lycopene is normally quite thermostable, but the oil in the tomato puree probably makes lycopene more sensitive to isomerization. Similar to the present results, Colle et al (2010a) also found a remarkable increase in 13-cis-lycopene concentration after a thermal treatment of a tomato puree with 5% olive oil during 10 min at 90°C whereas the change in the other isomers was less pronounced.…”

“…Crystalline lycopene can be solubilized in the oil which makes it more susceptible to degradation. At temperatures above 100°C, Colle et al (2010a) also observed oxidative degradation of lycopene during thermal processing of an olive oil/tomato emulsion.…”

“…Nevertheless, this mainly happens at extreme processing conditions or when oil is added (Colle, Lemmens, Tolesa, et al, 2010a;Colle, Lemmens, Van Buggenhout, Van Loey, & Hendrickx, 2010b). A positive effect of thermal processing, especially at high temperatures and long treatment times, on lycopene bioaccessibility in tomato products has also been shown (Colle et al, 2010a).…”

Temperature and high pressure stability of lycopene and vitamin C of watermelon Juice

“…The activation energy in this work was found higher than lycopene from tomato olioresine (11.5 -15 kcal/mole) (Hackett et al, 2004). Furthermore the activation energy of all-trans lycopene degradation was reported as 14.5 kcal/mol for standard lycopene (Lee and Chen, 2002), 6.7 kcal/ mole in olive oil-tomato emulsion (Colle et al, 2010) and 19.8 kcal/mol in safflower oil (Henry et al, 1998). Generally, the degradation of lycopene is high with an increase in temperature and treatment time, particularly when the temperature is above 100C.…”

New Developments in Lycopene Analysis by Spectroscopic and Chromatographic Techniques, Accompanied With Mathematical Modelling

“…Oxidation may also take place by the action of lipoxygenase, with the formation of hydroperoxides, and the presence of some antioxidants may inhibit this reaction. These processes may be reduced by using techniques that avoid contact with oxygen in air, such as freeze-drying, microwave, or others [25,26,[52][53][54][55][56][57][58].…”