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Lycopene, the pigment responsible for the characteristic deep red colour of ripe tomatoes and their products, plays an important role in human health. The stability of lycopene in tomato purée during storage was studied. Tomato purée was prepared from tomatoes grown in three different geographical regions of Croatia during two seasons. The samples of tomato purée were stored in the dark at 5, 15 and 25 °C and under light at 25 °C during a period of 6 months with constant monitoring of the changes of lycopene content. At the beginning of the storage there was no statistically significant difference (P<0.05) in lycopene content between the samples and geographic origin, while season significantly (P<0.05) influenced lycopene content. The value of lycopene content in all tomato purée samples significantly decreased (P<0.05) with increasing storage time for all the treatments. Light exposure significantly (P<0.05) facilitated degradation of lycopene.

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Acta Alimentaria
Authors:
K. Marković
,
I. Krbavčić
,
M. Krpan
,
D. Bicanic
, and
N. Vahčić

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 method.

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The present research is on the study of lycopene extraction from different raw and processed tomatoes, using traditional extraction methods with several solvents. The influences of the temperature and the light exposure were taken into consideration. The best extraction lycopene levels were obtained when chloroform:methanol mixture was used as solvent, followed by the hexane:acetone mixture and ethanol 95%. The lycopene is better extracted at room temperature compared with refrigeration and freezing temperatures. Lyophilized tomatoes contained the highest amount of lycopene (14.11 mg/100 g), followed by dried tomatoes with 6.01 mg/100 g, tomato juice with 11.38 mg/100 g, and the fresh tomatoes with 4.13 mg/100 g.

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Lycopene, found primarily in tomatoes, is a member of the carotenoid family and has potent antioxidant capability. The aims of the present study were: 1) to investigate the effect of grafting on lycopene content of tomatoes and 2) to evaluate the effects of different varieties on lycopene content (open-field with supporting-system, open-field with processing varieties) under the same ecological conditions. The effect of grafting on lycopene content was analysed in the case of two varieties, between the years 2001 and 2003. Lycopene content of tomato fruits decreased significantly by grafting. Ten commercial varieties of tomato produced in Hungary were examined for their lycopene content. Lycopene content of tomato turned out to be extremely diverse, and variable (63.0–155.0 mg/kg fresh weight). It was found that the variety of tomato is one of the most important determinants of lycopene content.

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Recently several studies have focused on the antioxidant activity of lycopene such as quenching of singlet oxygen and scavenging of peroxyl radicals. These properties may play a role in the prevention of different cancer and heart diseases. Tomato is one of the most important sources of lycopene. The main information on the effect of environmental parameters on quality and health-retaining constituents of tomato fruit is mostly related to temperature (air- and fruit canopy temperature) and light effects that might provide a stress to the fruit. Nowadays little is know about the direct effect of elevated CO2.The aim of the present work was to evaluate the effects of elevated CO2 in Perspex open top chambers (OTC) on the lycopene content of tomato fruit.Experiments on the effects of elevated CO2 concentrations showed mixed results. In this work it was found that concentrations of lycopene in a fruit decreased significantly when elevated CO2 was used. Elevated nitrogen sources generated only slight, but not significant difference in the lycopene concentration of tomato fruit.

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Tomato is one of the most important sources of lycopene. The effect of water supply was investigated on lycopene content of Daniela F1

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Acta Alimentaria
Authors:
J. Montiel-Ventura
,
J.J. Luna-Guevara
,
M.A. Tornero-Campante
,
A. Delgado-Alvarado
, and
M.L. Luna-Guevara

The aim was to examine conditions of convective drying and spray-drying to improve preservation of lycopene content in tomatoes. The weight, size, colour, pH and °Brix values were evaluated in fresh fruit (FF) and colour (L, a, b), hue, and chrome indices were analysed from dried tomatoes, too. Tomato paste was dried (40, 50, 60, and 80 °C with times of 540, 390, 270, and 240 min) under convection conditions and pulverized. In the encapsulation treatments core material with tomato powders of 50, 60, and 70%, shell solution of maltodextrin/gum arabic 1:1, flow rate of 4, 6, 9, and 12 ml min–1, and inlet air T of 160, 170, and 180 °C were used. The physicochemical properties of FF corresponded to a degree of ripeness for consumption. The a, a/b, and hue values of dried tomatoes at 50 °C significantly correlated to red colouring and higher lycopene content (47.98±1.49 mg/100 g). The encapsulation with 50% and 60% of tomato powders, 170 °C and 9 ml min–1 treatments increased lycopene contents to 10.41 mg/100 g, 10.20 mg/100 g, and 11.51 mg/100 g, respectively. The results demonstrated that the physicochemical and functional properties were influenced by drying conditions, providing useful information for increasing the stability of lycopene in dried tomatoes.

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Quantification of red pigment content of fruits using destructive techniques is expensive and it enables only the analysis of batches but not of individual items. This study examined the feasibility of using non-destructive, spectrophotometric method to predict one of the most valuable internal quality indices, lycopene, in individual tomato fruits. An open field experiment was conducted to study the effect of irrigation and potassium supplementation on the yield and lycopene content of processed tomato fruit. Three different treatments (regularly irrigated RI, irrigation cut-off 30 days before harvest CO, and rainfed RF unirrigated control) and two different potassium fertilisations (P) were applied. Regular irrigation significantly decreased the lycopene content of tomato fruits. The CO treatment resulted in the highest total lycopene without potassium supplementation. Potassium supplementation, given at the time before fruit maturity, significantly increased the lycopene concentration of cultivar Brigade F1, independently of irrigation. The closest correlation was at 700 nm R2=0.38 and R2=0.45, between reflectance and the (all-E)-lycopene and the (9Z)+(13Z)-lycopene isomers, respectively.

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resistant to Sclerotium rolfsii and southern root-knot nematode. Also, in another study, two interspecific hybrids (Beaufort and Multifort) derived from S. habrochaites were evaluated for nutritional quality parameters such as lycopene, β -carotene, and

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included ( Klee and Tieman, 2013 ). To develop tomato cultivars with high levels of quality criteria such as taste, aroma, colour, shape, and lycopene content is the most important task in modern breeding programs. Especially, lycopene is beneficial for

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