The lycopene content in pulp ad peel of five fresh tomato varieties

The lycopene content in pulp and peel of five fresh tomato cultivars, most common on Croatian market, was determined by spectrophotometry and the high-performance liquid chromatography (HPLC). Peels from the raw tomatoes contained more lycopene (expressed on a fresh basis) than the pulps: the ratio was 3.75±1.08 for spectrophotometric and 3.50±0.95 for HPLC measurements. Comparison of the results of lycopene content expressed on a dry weight basis revealed that the peel from raw tomato contains 1.74±0.36 times (spectrophotometry) more lycopene than the pulp as compared to a factor of 1.61±0.24 obtained by HPLC analysis. Fraction of the pulp in a whole tomato was found to vary between 89.9 and 95.2%, while that of tomato peel was between 4.9 and 10.1%. Nutritional habits in Croatia often include tomato-based food, all year around, prepared partlyof whole fresh tomatoes (including peel), partly of industrial tomato products (from which peel is often excluded). This study provides evidence that the peel of one of the most common varieties of tomatoes on Croatian market is richer in lycopene than the pulp and, moreover, that a diet including 100 g of raw tomatoes provides 1.35±0.29 mg lycopene from pulp as compared to 0.35±0.18 mg lycopene from tomato peel. In addition, results of this study will be useful in further attempts to quantify lycopene content of intact, whole tomatoes by means of the nondestructive, photoacoustic metho

Ultratraces of carotenes in tomato purees : HPLC-TLS study

The present study was designed to provide information about (i) the profile of carotene pigments and (ii) trace quantities of lycopene and -carotene left in tomato purées. The ultrasensitive method comprising HPLC and thermal lens spectrometric (TLS) detection enabled us to detect as low as 0.3 and 1.1 ng ml¿1 lycopene and -carotene in purée extracts, respectively. Total concentration of -carotene and lycopene (varying from 3 to 170 ng g¿1) in the examined tomato purées may serve as an indicator of the carotene-specific antioxidative capacity of these products. Although conventional spectrophotometry can be used to rapidly assess the quality of products derived from tomatoes, a highly sensitive and selective method such as HPLC-TLS is needed for reliable analyses of samples such as, for example, those subjected to inappropriate storage and/or handlin