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Total polyphenol content and in vitro antioxidant properties were investigated in five lager and three dark beers. The average concentration of total polyphenols in lager and dark beers was 376 and 473 mg l -1, respectively. All samples exhibited strong hydrogen-donating property and reducing power in a concentration-dependent manner. Beers also showed copper(II)-chelating ability and antioxidant property in Randox TAS measurement. The differences of polyphenol content and antioxidant characteristics between lager and dark beers were statistically not different. Antioxidant properties were dependent on the total polyphenol content of beers. The concentration of polyphenols and antioxidant properties except for chelating ability of beers measured in the same in vitro test system was very similar to those characteristics of white wine, while the extent of chelating ability of beers showed similarity to that of red wines. Studies evaluating the relative benefits of wine versus beer versus spirits suggest that moderate consumption of any alcoholic beverage is associated with lower rates of cardiovascular disease. Although beers have antioxidant capacity like white wines with having half the alcoholic content of wines, beers should be good sources of antioxidant polyphenols, and moderate consumption as a part of a well-balanced diet cannot be criticised either medically or socially and may have a beneficial effect on reducing oxidative disorders.

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The content of potentially antioxidant, anticarcinogenic and antiallergic flavonoid aglycons, quercetin, kaempferol, myricetin, apigenin and luteolin of 45 fruits were determined by RP-HPLC with UV detection. Fresh and dried fruits were purchased in the local markets in Budapest at a period of their most frequent consumption. Total flavonoid content of fruits varied between 0–1000 mg kg –1, the average concentration was about 30 mg kg –1 fresh weight. Quercetin could be detected in most fruits, namely in apples, pear, plums, sweet and sour cherry and berries between 10–53 mg kg –1. Luteolin at a concentration of 20 mg kg –1 was found in melons, apples, kiwi and lemon. Myricetin was in detectable amount in redcurrant, and at very high concentration in some berry fruits (mulberry 453 mg kg –1, raspberry 540 mg kg –1, blackberry 636 mg kg –1, strawberry 994 mg kg –1), and in walnut (4565 mg kg –1). Kaempferol and apigenin were not found in the fruits investigated. None of the five flavonoids was found in some variety of grapes, in peach, pear, banana, orange, grapefruit and tangerine, in nuts such as almond, pistachio, nuts, and in dried fruits such as raisin, date, fig and prunes. These data provide a basis for the evaluation of the average daily intake of Hungarian population and for an epidemiological evaluation of health-promoting effects of flavonoids. __

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In the present study the concentration of soluble solids (Brix°), total carbohydrate, total organic acid, lycopene, total polyphenol, hydroxymethylfurfural, and antioxidant capacity were investigated in tomato fruits at six ripening stages from mature green to fully red. In case of Brix o  and carbohydrate, the highest values were observed at the last stage of ripening. Carbohydrate content constitutes nearly 50% of the soluble solids. In mature green stage the lowest acid content was detected but in subsequent stages it did not change significantly. Polyphenol content remained almost the same during ripening, thus there were not significant differences found among ripening stages. In case of lycopene content, there were great differences among maturity stages. Lycopene accumulated mainly during deep red stage. The antioxidant characteristic of tomato fruit expressed as total antioxidant status (TAS) showed significant linear correlation with lycopene, polyphenol and hydroxymethylfurfural content and increased continuously during ripening period. Marked correlation was observed between lycopene content and formation of hydroxymethylfurfural, as well.

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Carrot is an important source of sugars. The objective of this study was to investigate the effects of water supply (precipitation + irrigation) on the concentration and ratio of fructose, glucose, and sucrose in carrot. Irrigation did not decrease the dry matter content and the summed concentration of the three measured sugars. Glucose accumulation was not influenced either by irrigation or by year. Low amount of precipitation during the early growing period was detrimental for fructose accumulation. Irrigation enhanced sucrose concentration, presumably by ensuring better photosynthetic activity. However, dry and hot weather during the irrigation cut-off period in 2011 also resulted in increased sucrose accumulation, presumably as a stress effect. It was found that irrigation did not influence the ratio of the three investigated saccharides at all, and even the growing year had just a slight effect on that.

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Acta Alimentaria
Authors: a: Lugasi, - Kéry, K. Hagymási, A. Blázovics, A. Lugasi, Sz. T. Kristó, J. Fehér, and Á. Kéry
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Caffeine is a bitter, white crystalline xanthine alkaloid that is synthesized in different parts of more than 60 plant species. In a previous study, caffeine content of 377 food samples obtained from the Hungarian market was measured by a validated HPLC technique. These analytical data were built up into a food composition database called NutriComp. Dietary caffeine intake of the Hungarian population was estimated based on the data of the National Nutritional Status Survey 2009. Daily caffeine intake of Hungarian adult males and females were 147±6.2 mg per capita (95% CI: 135–160), and 138±4.2 mg per capita (95% CI: 129–147), respectively. There was no significant difference between genders. The oldest men and women consumed significantly less caffeine than the people between 35–64 years of age. The main sources of caffeine are coffee and tea with 58–59%, and 35–37% of the total intake in men and women, respectively.

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Tomato quality factors such as size, firmness, colour, taste and nutritional content are important criteria for marketing of tomato fruit. The aim of present study was to evaluate the effects of different types of varieties and cultivation technologies (forcing, open-field with supporting system, open-field with processing varieties) on the ingredient content of tomato fruit. The soluble solids (°Brix), carbohydrate, organic acid, lycopene and ascorbic acid contents were measured. Average soluble solids content ranged from 5.2 to 8.7%. The highest °Brix was observed in the fruits of a cherry type tomato, namely Favorita (8.7%). Carbohydrate content constitutes nearly 50% of the °Brix. The highest carbohydrate content was observed for Favorita and Cheresita (both cherry type tomatoes), whereas the lowest was detected in Falcorosso, a processing variety. Low acid content was found in Nívó and Delphine F 1 cultivars (processing and eating variety, respectively). The sugar-acid ratio was 40% higher in the case of cherry type tomatoes than in the other varieties. Average lycopene content of examined tomato varieties turned out to be extremely diverse (48–134 mg kg −1 ). Ascorbic acid levels did not differ so much, ranging from 226 to 381 mg kg −1 . In case of open-field cultivation with supporting system, cherry type varieties showed significantly higher °Brix and carbohydrate content than those of round tomato type with average fruit weight of 100∓130 g. All varieties examined produced significantly higher organic acid content in forcing as compared to the values of round tomato varieties cultivated in open-field with supporting system and processing varieties. Lycopene content of tomato fruits from greenhouse was higher than that of fruits from field. Processing varieties yielded significantly higher lycopene content than the others.

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Culinary herbs and medicinal plants could be used as natural food ingredients to replace synthetic antioxidants. Two natural antioxidant preparations, namely Rosmol (liquid) and Rosmol-P (powder) were produced by extraction from a mixture of medicinal plants belonging to the Lamiaceaefamily, such as rosemary (Rosmarinus officinalis L.),self heal(Prunella vulgaris L.)hyssop(Hyssoppus officinalis L.)and lemon balm (Melissa officinalis L.). The main active compound of the extract is supposed to be a phenolic (caffeic) acid derivative. The total polyphenol content of the preparations is very high, 8.72 g l-1for Rosmol and 93.7 g kg-1for Rosmol-P. The products acted as primary and secondary antioxidants, chelating transitional metal ions and inhibiting the autoxidation of linoleic acid. Rosmol and Rosmol-P scavenged free radicals formed during Fenton type reaction measured by chemiluminometry, and also exhibited strong antioxidant property in Randox TAS measurement. The antioxidant activity of the products was unchanged after six months of storage. According to the in vitro studies, the products are suitable to use as antioxidant ingredients instead of synthetic ones in lipid containing food products.

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A two-year open field experiment was carried out to study the effect of elevated carbon dioxide (CO2) and nitrogensupply on fruit components of tomato. Korall determinate growth type processing tomato cultivar plants were planted and cultivated for the entire growing season in open top chambers (OTC) in years 2007 and 2008. Compared with the control (350 ppm) CO2 enrichment (700 ppm) significantly decreased the lycopene content at all three harvest dates in both years, but higher supply of nitrogen and 700 ppm CO2 resulted in significantly higher lycopene values in second year. Elevated nitrogen concentration combined with 700 ppm CO2 significantly increased the Brix, sugar content, total phenolics, and total antioxidant status (TAS) of tomato fruits.

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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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