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1.
Organic food is associated by the general public with improved nutritional properties, and this has led to increasing demand for organic vegetables. The objective of this study was to investigate whether there were any differences in the micronutrient contents in organic and conventional tomatoes (Solanum lycopersicum L.). Two tomato cultivars ‘Lladó’ and ‘Antillas’ grown organically and conventionally were compared regarding their micronutrient in terms of K, Ca, Na, Mg, Fe, Zn, Mn, Cu, lycopene, ß‐carotene, ascorbic, malic and citric acids, and total phenolic compound content. Cultivar ‘Lladó’ had the highest concentration of the nutrient lycopene, ß‐carotene, Fe, Zn, Mn and Cu. Where cultivation method affected the concentration of ascorbic acid and Mn, only one cultivar was affected. For all nutrients examined, cultivar differences were greater than differences because of cultivation method. This study confirms that the most important variable in the micronutrient content of tomatoes is cultivar; organically grown tomato is no more nutritious than conventionally grown tomato when soil fertility is well managed.  相似文献   

2.
BACKGROUND: Soluble sugars and cell wall polysaccharides are well known for contributing to a range of ‘quality’ characteristics of fresh vegetables such as flavour, texture and healthy properties. Red‐ripe berries of 14 cultivars of cherry tomatoes and four cultivars of high‐pigment tomato hybrids, cultivated in the south of Italy, were analysed for their content of these important qualitative parameters. RESULTS: Sakura appeared to be the cultivar with the highest amount of soluble sugars (53 g kg?1 fresh weight (f.w.)), mainly glucose and fructose, and, hence the ‘sweetest’ among cherry tomatoes. High‐pigment tomatoes, especially HLY02 and HLY13, showed a soluble sugar content much lower than cherry tomatoes, as expected for industrial, normal‐size tomatoes. Variations in the fructose/glucose ratio, of between 0.68 and 1.48, were evidenced among the different tomato cultivars. Cell wall polysaccharides isolated from whole fresh red‐ripe berries of each cultivar were analysed chemically. The amount of matrix polysaccharides (0.9–3.4 g kg?1 f.w.) and cellulose (0.16–1.86 g kg?1 f.w.), as well as their glycosidic composition, showed significant differences among the different cultivars. Cellulose to matrix polysaccharide ratio was highly variable and ranged between 0.06–1.44 and 0.17–0.77 in cherry and high‐pigment tomato cultivars, respectively. CONCLUSION: The differences evidenced in the total soluble sugar and cell wall polysaccharide composition, not only among different types of tomatoes but also different cultivars within the same typology, may play a fundamental role in the quality of tomatoes and deserve further investigations. Copyright © 2008 Society of Chemical Industry  相似文献   

3.
This study examines physicochemical changes in newly developed and existing tomato varieties at different levels of maturity. Serum viscosity is an important factor in the selection of tomato varieties for processing. Most of the attributes indicative of quality for fresh and paste tomatoes occurred at a less mature stage and declined with maturity. The canned varieties ‘H9888,’‘H8892’ and ‘H9780’ had a greater ascorbic acid content and antioxidant capacity. The highest lycopene contents were found in the varieties ‘H9888,’‘CXD254,’‘CXD222’ and ‘H9780’. Total soluble solids levels increased with maturity. The highest acidity values occurred in canned ‘Shasta’, ‘CXD254’ and ‘H9780’ varieties. Mid‐ and late‐season varieties harvested at an early stage produced thicker pastes with greater serum viscosity and acidity than tomatoes harvested at other points in the ripening process. The best results were obtained from canned samples of ‘H9888,’‘CXD254’ and ‘H9780.’  相似文献   

4.
BACKGROUND: Modern consumers are increasingly interested in their personal health and expect the food they purchase to be tasty and attractive while being safe and healthful. The aim of this study was to determine the commercial quality, characterise the antioxidant capacity and quantify the major bioactive compounds of 12 cultivars of loquat fruits in order to establish a database for utilising these germplasm resources. RESULTS: Of the 12 cultivars, ‘Guanyu’ produced the biggest fruits, while ‘Tianzhong’ and ‘Bingtangzhong’ had the highest soluble solids content but the lowest titratable acidity. ‘Taipinghong’ was reddest in colour. Sucrose, fructose, glucose and sorbitol were the major sugars in loquat fruits, with the highest total sugar content being observed in ‘Bingtangzhong’ and ‘Tianzhong’. Phenolics and flavonoids were the main bioactive compounds and were abundant in ‘Tianzhong’ and ‘Zhaozhong’. ‘Taipinghong’ had the highest total carotenoid content, while ‘Qingzhong’ had the highest vitamin C content. ‘Tianzhong’, ‘Bingtangzhong’ and ‘Ninghaibai’ showed higher antioxidant activity than the other cultivars, as measured by assays of 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and 2,2‐azino‐bis(3‐ethylbenzthiozoline‐6‐sulfonic acid) (ABTS) scavenging and ferric‐reducing/antioxidant power (FRAP). CONCLUSION: Commercial fruit quality, major bioactive compound content and antioxidant capacity varied greatly among the 12 cultivars. ‘Bingtangzhong’ and ‘Tianzhong’ were the highest‐ranking cultivars based on their good commercial quality and high nutritional value. The loquat fruits with higher total phenolic and flavonoid contents also had clearly higher antioxidant capacities. Copyright © 2011 Society of Chemical Industry  相似文献   

5.
Forty‐two blueberry cultivars (thirty‐six Vaccinium ashei, three V. ashei derivative hybrids and three northern highbush standards) were evaluated for their antioxidant capacities and other fruit quality attributes over two growing seasons. Total anthocyanins, phenolic content and antioxidant capacities varied substantially among species and cultivars. ‘Early May’ (V. ashei) had the highest amounts of anthocyanins, phenolics and antioxidant capacity. Cultivars from V. ashei hybrid derivatives had lower mean antioxidant components than those from northern highbush standards or V. ashei. The antioxidant capacity, as well as total anthocyanins and phenolics, had significant cultivar × year interactions. Correlation coefficient between years for total anthocyanins, total phenolics and oxygen radical absorbance capacity were high with values of 0.86, 0.81 and 0.93, respectively. Similar interactions were observed for soluble solids content (SSC), sugar, titratable acid and organic acids among cultivars both within and across the growing seasons. Correlation coefficients between years for SSC, fructose, glucose and sucrose were 0.78, 0.71, 0.83 and 0.96, respectively. Fructose and glucose were detected as two major sugars with sucrose as a minor constituent. ‘Clara’ contained the highest amounts of SSC and sugars, while ‘Satilla’ had the lowest. In general, V. ashei cultivars had a higher mean SSC and sugar contents than did the hybrid derivatives or the northern highbush standards. Cultivars of V. ashei contained higher malic acid than citric acid, whereas in hybrid derivatives and northern highbush cultivars, citric acid was the predominant organic acid. The diversity in the amount of these fruit quality attributes and antioxidant capacities presents a great opportunity for genetic improvement of blueberries through breeding programmes. The objective of the study was to identify blueberry cultivars with high antioxidant activity and good fruit quality, so they can be used as parents for future blueberry breeding programmes to develop new cultivars with higher antioxidant activity.  相似文献   

6.
BACKGROUND: Apricot is one of the most popular Prunus species grown in the temperate zone and great variation in the contents of primary and secondary metabolites has been reported in its fruit. However, little is known on the phenolic profiles and antioxidant potential of important local cultivars. The objective of the study was to identify valuable parental lines for breeding of cultivars with high health‐promoting effects. RESULTS: Primary metabolites (sugars, organic acids) and secondary metabolites (phenolics) were quantified by high‐performance liquid chromatography–mass spectrometry (HPLC/MS) in fruit of 13 apricot cultivars: total sugars ranged from 59.2 to 212.5 g kg?1 fresh weight (FW) and total organic acids from 4.2 to 20.8 g kg?1 FW. Four hydroxycinnamic acids and three flavonols were quantified; their content was significantly higher in skin compared to pulp. Similarly, antioxidative potential was significantly higher in skin and ranged from 125.4 to 726.5 mg ascorbic acid equivalents kg?1 FW. A positive correlation between total phenolic content and antioxidant potential was determined. Multivariate analysis subdivided the cultivars into five major groups, mostly influenced by the content of individual and total phenolics as well as the antioxidant potential of apricot skin and pulp. CONCLUSION: In regard to high phenolic content in connection with antioxidant potential, three cultivars stand out as the richest in analyzed quality parameters: ‘Mula Sadik’, ‘Bergeron’ and ‘Chuan Zhi Hong’. They also contained high amounts of primary metabolites and should be promoted for further planting and included in apricot breeding programs. Copyright © 2010 Society of Chemical Industry  相似文献   

7.
BACKGROUND: Consumption of broccoli is increasing steadily worldwide because of the interest in its bioactive composition and nutritive value for health promotion. Novel broccoli cultivars to be established under current adverse conditions in production areas (aggressive environmental conditions and saline irrigation waters) need to maintain physical and nutritional quality for consumption and year‐round supply to the markets. The newly introduced cultivars ‘Naxos’ and ‘Parthenon’ have been selected as potential candidates to replace the currently underperforming ‘Nubia’ variety. We aimed to compare the physical and phytochemical quality (glucosinolates, hydroxycinnamic acids, flavonoids, vitamin C and minerals), as well as the in vitro antioxidant capacity of these three cultivars under conditions of environmental stress. RESULTS: ‘Parthenon’ showed equal productivity and nutritional composition to ‘Nubia’, whereas ‘Naxos’ presented in general the best results when compared to ‘Nubia’ and ‘Parthenon’. For phenolic compounds ‘Nubia’ presented the highest contents, although ‘Naxos’ seemed better adapted to saline stress conditions, as suggested by the lowest degree of variation in the contents of healthy phytochemicals, including phenolic compounds, when grown under such conditions. CONCLUSION: ‘Naxos’ broccoli performed best and is a suitable candidate to replace ‘Nubia’ for marketable, nutritive and phytochemical quality, especially in areas of production under adverse conditions as found in Mediterranean southeast Spain (semiarid climate with saline irrigation water). Copyright © 2011 Society of Chemical Industry  相似文献   

8.
Sour cherry (Prunus cerasus L.) cultivars native to Hungary and some of them grown worldwide, display great phenotypic variability. Eleven sour cherry cultivars were analysed for their main quality attributes including fruit weight, soluble solid content, acidity, pH, specific sugars (glucose and fructose), antioxidant capacity as well as total polyphenolic (TPC), total anthocyanin (TMAC) and vitamin C contents. Results showed wide variation in both fruit quality and antioxidant parameters of Hungarian sour cherries. The anthocyanin contents varied from 11.3 to 93.5 mg/100 g. An amarelle‐type cultivar, ‘Pipacs 1’ showed the highest antioxidant capacity (21.85 mmol AA L?1), TPC (49.04 mg GA L?1) and vitamin C (8.98 mg/100 g) content. Key enzymes in anthocyanin biosynthesis were expressed in both yellow‐coloured flesh and red skin of ‘Pipacs 1’ fruits at all ripening stages. The detected diversity presents a choice that can satisfy different consumer preferences, and meet specific nutritional requirements.  相似文献   

9.
Lycopene, a natural red pigment found in tomato, is correlated with reduced incidence of some cancers. Forty tomato varieties, including cluster F1 hybrid tomatoes, round breeding line tomatoes (Lycopersicon esculentum Mill) and cherry tomato types (L esculentum var cerasiforme), grown under greenhouse and field conditions were evaluated for their lycopene content using high‐performance liquid chromatography (HPLC) and spectrophotometry. Lycopene content varied significantly among the tomato varieties, with cherry tomato types having the highest lycopene content. Greenhouse‐grown cluster and round tomatoes contained more lycopene (mean = 30.3 mg kg?1) than field‐grown tomatoes (mean = 25.2 mg kg?1), whereas cherry tomato types had a higher lycopene content in field‐grown (mean = 91.9 mg kg?1) than in greenhouse‐grown (mean = 56.1 mg kg?1) fruits. HPLC analysis of lycopene isomeric forms revealed a higher content of all‐trans isomers in all tomato genotypes examined. However, the cis isomeric form was exceptionally higher in the field‐ and greenhouse‐grown cherry tomato L esculentum var cerasiforme cv Gardener's Delight, which contained ~9.3 and 9.9 mg kg?1 cis isomers respectively. Results indicate that genetics and choice of cultivation environment may have a strong influence on tomato lycopene content. Copyright © 2005 Society of Chemical Industry  相似文献   

10.
ASSESSING LYCOPENE CONTENT IN CALIFORNIA PROCESSING TOMATOES   总被引:1,自引:0,他引:1  
Tomatoes constitute the main source of lycopene in the U.S. diet. Growing interest in the potential health‐protective role of lycopene is bringing attention to the content of lycopene in tomatoes. A wide range of lycopene content (55–181 mg/kg) was observed in juice prepared from selected cultivars of tomatoes grown in nine California counties. A comparison of cultivars H 8892, H 9665 and Halley 3155 grown in Colusa, Fresno, San Joaquin and Yolo counties during three seasons concludes that mean lycopene concentrations were significantly greater (P < 0.01) in 2000 (106 mg/kg) than in 1999 (101 mg/kg) and 2001 (88 mg/kg). An evaluation of nine processing tomato cultivars harvested in one season on four separate dates indicated that lycopene concentration of tomatoes decreases with maturation on the plant. Lycopene concentration of tomatoes is dependent on the growing season, location, cultivar and maturity.  相似文献   

11.
BACKGROUND: Numerous studies have compared ecologically produced foods with conventionally produced competitors, with contradictory results. In this work we investigated the physicochemical, microscopic and sensory properties of two tomato cultivars (Lladó and Antillas), which were grown both ecologically and conventionally. RESULTS: The physicochemical variables size, weight, firmness, total acidity, pH, total solids content, lycopene content and CIELab a*, b*, a*/b*, C* and h* were all significantly influenced by cultivar, as were the sensory variables external colour, internal colour, external aroma intensity and flavour persistence. Compared with conventionally grown tomatoes, ecologically grown tomatoes had larger total solids contents and larger values of the CIELab colour parameters b*, C* and h*, but smaller sizes and weights and smaller values of the CIELab parameter ratio a*/b*; however, these physicochemical differences were insufficient for growing method to have a significant influence on any of the sensory attributes that were evaluated. Microscopy showed the influence of cultivar on lycopene content, but no other structural differences were observed between the two cultivars or between tomatoes grown by different methods. CONCLUSIONS: The statistically significant differences found in this study were mainly between cultivars rather than between tomatoes grown using different management practices. Copyright © 2009 Society of Chemical Industry  相似文献   

12.
BACKGROUND: Like sweet orange (Citrus sinensis), tangerine (Citrus reticulata) is another citrus crop grown widely throughout the world. However, whether it shares a common mechanism with sweet orange in forming a given mastication trait is still unclear. In this study, three ‘Nanfeng’ tangerine cultivars, ‘Yangxiao‐26’ (‘YX‐26’) with inferior mastication trait, elite ‘YX‐26’ with moderate mastication trait and ‘Miguang’ (‘MG’) with superior mastication trait, were selected to investigate the formation mechanism of mastication trait. RESULTS: ‘MG’ had the lowest contents of total pectin, protopectin and lignin and the highest gene expression levels of citrus polygalacturonase (PG) and pectin methylesterase (PME) at the end of fruit ripening, whereas ‘YX‐26’ had the lowest water‐soluble pectin (WSP) content, the highest lignin content and the lowest PG and PME expression levels. The contents of cellulose and hemicellulose were similar among the three tangerines. CONCLUSION: The fruit mastication trait of C. reticulata was determined by the proportions of WSP and protopectin as well as lignin content, not by cellulose and hemicellulose contents. Pectin content could be a major contribution to the feeling of mastication trait, while PG and PME exhibited an important role in forming a given mastication trait according to the present results as well as previous results for C. sinensis. Copyright © 2011 Society of Chemical Industry  相似文献   

13.
BACKGROUND: Two extraction methods employing tetrahydrofuran and phosphate buffer (pH 7.4) respectively were used to process tomatoes. The antioxidant contents and antioxidative properties of extracts of four tomato cultivars were measured. To evaluate the overall antioxidative capacity of the tomato extracts, an antioxidative performance index (API) was used, defined as the average of four antioxidative assays, i.e. relative reducing power, ferrous ion‐chelating ability, 2,2‐diphenyl‐1‐picrylhydrazyl free radical‐scavenging activity and superoxide radical‐scavenging activity. RESULTS: A linear correlation between the total antioxidant content (TAC) and API of tomato extracts was found that was independent of the extraction method and tomato cultivar. CONCLUSION: The concept of representing multiple antioxidant activities by a single index is useful for evaluating the overall antioxidative capacity of antioxidants in tomatoes. Copyright © 2007 Society of Chemical Industry  相似文献   

14.
The influence of two different harvest times (optimal and 4 days earlier) on thirty flavour compounds, titratable acid and sugars as well as consumer acceptance of four old and endangered tomato cultivars (‘Ananas’, ‘Auriga’, ‘Green Zebra’ and ‘Lukullus’) was analysed. In most cases, cultivar type had a greater effect on the volatiles profile than harvest times. Sugar contents were mostly higher at optimal harvest compared with early harvest, whereas acid content was in most cases not affected by harvest time. Consumers perceived differences in several visual and sensory aspects between cultivars as well as harvest times. The optimal harvest was regularly preferred to or at least regarded as equal to the early‐harvest time. Sensory evaluation was poorly related to the aroma volatile profile and only partly to the acid and reducing sugar contents of tomatoes. This was probably owing to the special external characteristics of the tomatoes: differing in size, shape and colour from the ‘normal’ red types.  相似文献   

15.
BACKGROUND: The aim of this study was to examine how different environmental factors (temperature, solar radiation, and vapour‐pressure deficit [VPD]) influenced nutritional quality and flavour of cherry tomato fruits (Solanum lycopersicum L. cv. Naomi) grown in two types of experimental Mediterranean greenhouses: parral (low technology) and multispan (high technology). RESULTS: Fruits were sampled three times during 3 years (2004, 2005 and 2006): at the beginning, middle and end of the fruit production period. Values for temperature, solar radiation, and VPD peaked in the third sampling in both greenhouses; values were higher in the parral‐type greenhouse, triggering abiotic stress. This stress reduced the accumulation of lycopene and essential elements, augmenting the phytonutrient content and the antioxidant capacity of tomatoes. During the third sampling, sugars were increased while organic acid content diminished, producing tomatoes with a sweeter‐milder flavour. The parral greenhouse produced tomatoes with higher phenolic compounds and ascorbic acid contents, together with a greater antioxidant capacity, without showing differences in flavour parameters. CONCLUSION: The higher phytonutrients content and antioxidant activity during the environmental stress, more pronounced in parral than multispan greenhouse, together with the sweeter‐milder flavour, conferred a notable nutritional benefit, which considerably improved the nutritional and organoleptic quality of these tomatoes. Copyright © 2010 Society of Chemical Industry  相似文献   

16.
Approximately 25% of the processed tomatoes grown in California are made into value‐added foods such as whole peeled and diced tomatoes. Peel removal is the first step in this process, and it must be optimized for both quality and yield. The effect of peeling conditions on tomato cultivars Halley 3155 and Heinz 8892 (H 8892) was evaluated. Considerable texture loss results from peeling; however, firmness was greater for cv. Halley 3155 than for cv. H 8892 regardless of peeling conditions utilized. Peeling under low steam pressures (12 psig) was insufficient to adequately peel either cultivar. While high pressure steam (18 psig) was more efficient at peel removal, increasing vacuum level from 20 in. to 24 in. did not improve peelability of either cultivar. Because cultivar affected peelability and yield, specific tomato cultivars should be evaluated and directed to either paste or whole peeled and diced tomatoes as appropriate.  相似文献   

17.
In this study, we investigated the effects of fruit ripening stage on the physico-chemical properties and nutritional contents of three greenhouse grown tomato cultivars (‘Monika’, ‘Isabella’ and ‘Cherry’). Significant changes (p?≤?0.05) occurred in fruit colour, total soluble solids, protein, fibre, ascorbic acid (vitamin C) and lycopene content at different stages of ripening. ‘Cherry’ tomato contained significantly (p?≤?0.05) higher total soluble sugar and several nutrients including fibre. However, the plum-type tomato cultivars (‘Monika’ and ‘Isabella’) contained higher vitamin C and lycopene than ‘Cherry’ tomato. In all tomato cultivars, it was found that up to 50% of final lycopene content occurred during the final phase (from red to deep red colour) of fruit ripening.  相似文献   

18.
Regular consumption of tomatoes has been associated with decreased risk of chronic degenerative diseases. Epidemiological findings confirm the observed health effects are due to the presence of different antioxidant molecules such as carotenoids, particularly lycopene, ascorbic acid, vitamin E and phenol compounds, particularly flavonoids. In this work, eight components contributing to the healthy quality of tomato (i. e. lycopene, beta-carotene, other carotenoids, flavonoids, phenolic acids, vitamins C and E, dry residue) were studied in the framework of breeding programs aiming to develop nutritional superior genotypes. Twelve tomato advanced breeding lines and six open pollinated cultivars were grown in strictly controlled conditions and analysed for their content of antioxidants. Among the 18 genotypes analysed, 10 showed a high level of total carotenoids, 6 high level of beta-carotene, 9 high lycopene levels, 15 high flavonoids and 2 relevant concentration of vitamin E. Based on such data and on a literature survey on tomato composition, an index, called index of antioxidant nutritional quality (I(QUAN)), was proposed as a tool to address the breeding programs in selecting tomato genotypes with antioxidant nutritional qualities.  相似文献   

19.
BACKGROUND: In this study, differences in contents of phenolic compounds and fatty acids in pecan kernels of organically versus conventionally grown pecan cultivars (Cheyenne, Desirable, and Wichita) were evaluated. RESULTS: Although nine phenolic compounds (gallic acid, catechol, catechin, epicatechin, m‐coumaric acid, chlorogenic acid, ellagic acid, caffeic acid and an ellagic acid derivative) were identified in the methanol extract (80% methanol) of defatted kernels, only three compounds (gallic acid, catechin and ellagic acid) existed in sufficient amounts to accurately quantify levels in different cultivars and to study differences in organic versus conventional cultivation. Levels of ellagic acid and catechin found in organically grown ‘Desirable’ were fourfold and twofold higher than in conventional samples, respectively. Furthermore, significant differences in these two compounds were also observed when comparing values between cultivars. Oil content was also significantly greater only in organically grown ‘Desirable’. Oleic acid was the major fatty acid present and its content was significantly higher in organically versus conventionally grown ‘Desirable’ pecans, while there was no difference in levels of oleic acid in ‘Wichita’ and ‘Cheyenne’. On the other hand, linoleic acid content was significantly less in organically versus conventionally grown ‘Desirable’ pecans. CONCLUSION: Overall, these results showed that the effects of cultural differences (i.e. organic versus conventional cultivation) on kernel composition largely depend on the type of pecan cultivar. Copyright © 2009 Society of Chemical Industry  相似文献   

20.
Greenhouse grown tomatoes (cvs ‘Durinta’, ‘Favorita’ and ‘Liberto’) were harvested green and vine ripe. Colour measurements and chemical analyses were performed on green, post‐harvest red and vine‐ripe fruits. Partial least square (PLS) regression was applied to predict the ferric reducing ability of plasma (FRAP) by means of colour measurements (L*, a* and b*). The PLS showed that 78% of the variation in colour were able to predict 74% of the variation in FRAP value. Chemical variables and colour variables together were able to predict 88% of the variation in FRAP by means of PLS regression. Linear regression showed a high negative correlation between high values of L*, b* and FRAP, and a high positive correlation between titratable acidity, a*, hue, a*/b*, soluble solids, vitamin C, dry matter and FRAP values. Thus, colour measurements of intact tomatoes can be used as a non‐destructive method to assess total antioxidant capacity of tomatoes.  相似文献   

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