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1.
BACKGROUND: Tomato, one of the most important vegetables worldwide, contains a range of flavonoids and phenolic acids in addition to lycopene, which are regarded as potentially useful compounds with respect to health benefits. Composition data in fresh tomatoes vary due to genetic and environmental factors and cultural practices. Breeding programs aim to produce tomatoes with enhanced levels of flavonoids and other phenolics. RESULTS: The present paper gives an overview of flavonoids, stilbenoids and other phenolics reported to occur in tomato fruits. Contents are reported for a wide range of cultivars and types. Metabolism of phenolics during fruit maturation and tissue location are described, and an overview of measured contents is given. Effects of environmental conditions and cultural practices are estimated using available literature. Recent literature on transgenic tomatoes is included, and possibilities for regulating phenolic contents in tomatoes are discussed. CONCLUSION: The literature review clearly discloses a rapidly growing interest in flavonoids and other phenolics in tomato fruits and products made thereof. This is particularly connected to the antioxidant properties of these compounds as well as other possible health effects. Choice of cultivar and effects of environment and agronomic practices are important factors with respect to phenolic qualities and quantities of tomatoes. Copyright © 2009 Society of Chemical Industry  相似文献   

2.
BACKGROUND: Tomato fruits are characterized by a good nutritional profile, including different bioactive compounds such as carotenoids, phenolic compounds and ascorbic acid. The objective of this study was to analyze the content of bioactive compounds in the fruit and the infection by Phytophthora infestans of 28 tomato genotypes from organic outdoor production. The relationship between bioactive compounds in the fruit and infection with P. infestans was estimated. Field experiments were carried out in 2004 and 2005 at two locations in central Germany. RESULTS: Significant variation among genotypes, locations and years was observed for the content of lycopene, ascorbic acid, total phenolic compounds, antioxidant capacity and the infection level of P. infestans. Antioxidant capacity seemed to be influenced mainly by the phenolics and was highest in small fruits, which were less infected with P. infestans. CONCLUSION: The large genetic variation among tomato genotypes for the content of bioactive compounds in their fruit allows for selection gains. None of the investigated bioactive compounds can be recommended for the indirect selection for increased field resistance against P. infestans. Copyright © 2011 Society of Chemical Industry  相似文献   

3.
Food Science and Biotechnology - This study was conducted to assess the physicochemical changes and overall nutritional implications of greenhouse-grown “TY Megaton” and...  相似文献   

4.
Mature-green tomato fruit cv Calypso were stored at 5, 7,12 or 19oC for 0, 3, 9, 12 or 21 days, ripened at 19oC for 3 or 6 days and analysed for surface colour (aL/bL ratio), firmness, and tissue disorganisation in chill-damaged (pitted) and adjacent unpitted tissues. Manifestation of cell disorganisation and death was evident in pitted tissues. Alternaria spp, Stemphylium spp, Penicillium spp and Aureobasidium spp were isolated from pitted tissues. Fruit stored for either 9 or 12 days at 5 or 7°C subsequently ripened to an acceptable colour, but longer storage times inhibited satisfactory colour development. After storage at 12 or 19°C, fruit surface colour improved progressively with time. Loss of fruit firmness was highest at 19°C but decreased with increasing temperature from 5 to 12°C, showing biphasic maxima firmness loss on days 9 and 21. Surface pits occurred at the stem end and in the equatorial region of the fruit. Fruits were also stored at 7, 12 or 19°C for 10 or 20 days and then ripened at 19°C for 10 days before evaluation of visible defects; these were greatest at 7°C followed by 19°C and were lowest at 12°C.  相似文献   

5.
Characterisation of the optical properties of the internal structures of tomatoes enhances assessment of the composite appearance. Reflectance colorimetry and the Kubelka-Munk analysis to distinguish three distinct maturity groups of tomatoes were tested. Differences in the scatter, absorption and internal transmittance were found amongst the component structures of the intact tomato. Tomato fruit was also pulped and a range of dilutions prepared. The decrease in scatter, absorption and increase in internal transmittance with increased dilution suggests the importance of optical properties with changes in concentration.  相似文献   

6.
BACKGROUND: Three near‐isogenic lines of cv. Gimar differing in ethylene production were used to evaluate the influence of salinity on fruit quality. Plants were grown in rockwool culture and were irrigated with nutrient solution with electrical conductivities (ECs) of 3 and 8 mS cm?1, which corresponded to 0 and 10% of sea water. For fruits picked at ‘red‐turning’ and ‘red‐ripe’ stages physico‐chemical parameters, ethylene, ascorbate and organic acid content, and cell reductive power were analysed. RESULTS: The same response was observed in all genotypes: the higher salinity growth solution increased dry matter content, total soluble solids (TSS) and titratable acidity but reduced crop yield. Ascorbic acid and also organic acid contents showed a greater accumulation with ripening in the mutant genotypes: this might be due to a slowing of ripening. Our data confirm the lack of any relationship between the larger accumulation of TSS and ethylene production in the fruits of salt‐treated plants. CONCLUSION: These findings suggest that although salinity (10% sea water) reduces fruit yield, it does not have a negative effect on quality. So, it seems possible that controlled use of diluted sea water, combined with suitable tomato genotypes might represent a valid alternative to fresh irrigation water. Copyright © 2007 Society of Chemical Industry  相似文献   

7.
BACKGROUND: Tomato producers are looking for alternatives to protect their crops against the tomato yellow leaf curl virus (TYLCV), including replacement of cultivars with other more resistant ones. Major chemical components, sugars, mineral composition, organic acids, lycopene, total phenols and hydroxycinnamic acids were determined in six tomato cultivars, three of them (Boludo, Dorothy and Tyna) resistant, and the other three (Daniela, Dominique and Thomas), non‐resistant against TYLCV. RESULTS: The Daniela cultivar showed the greatest difference with respect to the others, mostly due to the higher content of soluble solids. The major significant differences between the mean values according to the cultivar and resistance against the TYLCV were observed for total soluble solids, pH, ascorbic acid, total phenols and hydroxycinnamic acids. High coefficients of correlation were found between glucose and fructose, and among ferulic, caffeic and p‐coumaric acids. CONCLUSION: Linear discriminant analysis made it possible to differentiate tomato samples according to the cultivar. A clear varietal influence on the chemical composition was observed; however, resistance or non‐resistance against TYLCV does not seem to influence the chemical composition. Copyright © 2008 Society of Chemical Industry  相似文献   

8.
SRE处理对采后番茄贮藏效果的影响   总被引:1,自引:0,他引:1  
研究乙醇的新型固体缓释剂(slow-release ethanol,SRE)对采后番茄贮藏效果的影响。以番茄‘粉太郎’为试材,破色期采收,在20℃、相对湿度85%的条件下贮藏,用SRE处理,以不做任何处理为对照,测定番茄贮藏期间品质特性、乙烯释放量及多聚半乳糖醛酸酶(polygalacturonase,PG)和纤维素酶活性。结果表明:SRE处理可以提高果实亮度,延缓果实质量损失率降低,减少可溶性固形物含量损失,保持一定硬度,同时提高了果实贮藏后期糖酸比,比对照果实延缓变红6 d。SRE处理显著降低乙烯释放量和PG、纤维素酶活性。综上,SRE处理可以延缓采后番茄果实成熟衰老,从而延长货架期,使番茄更长久保持风味品质。  相似文献   

9.
ABSTRACT: High-pressure-treated tomato puree was investigated for changes in carotenoid extractability, antioxidant activity, glucose diffusion, and water binding. No effect of pressurization was observed in the total concentrations of the main water-insoluble antioxidants, lycopene and β-carotene, extracted with tetrahydrofuran, but lower recovery of carotenoids with petroleum ether suggested structural changes in the tomato pulp tissue, due to processing. Total antioxidant capacity of the water-soluble fraction was unchanged immediately after pressure treatment, but was better preserved during 21 d at 4 °C, compared with untreated samples. High-pressure treatment resulted also in enhanced water binding. Glucose diffusion through dialysis tubing was lower after high-pressure treatment, leading to a higher glucose retardation index.  相似文献   

10.
BACKGROUND: The agricultural production system and cultivation practices are critical factors in determining yield and food nutritional quality. Controversy remains regarding whether or not organic foods have a nutritional advantage when compared with their conventionally produced counterparts. In this study the effect of conventional and organic production systems on yield, physicochemical and nutritional properties of four field tomato cultivars (Perfectpeel, Rio Grande, Hypeel 108 and Firenze) was determined. In the organic system, different fertiliser combination treatments were used. RESULTS: When production system data were combined, marketable yield was not affected by cultivar. When averaged across cultivars, organic yield was about 63% of conventional yield. The production system affected fruit soluble solids, pH, titratable acidity and firmness only in some cultivars. However, no effect was found on lycopene and total phenolics in all cultivars. In the organic system, fertiliser combination treatments affected tomato yield of Rio Grande and fruit quality of Firenze and Hypeel 108. A general trend of higher quality data was obtained by using mixed compost C2 combined with its extract and codahumus 20. CONCLUSION: The production system affects tomato yield and some fruit quality attributes. The effect on fruit quality varies among cultivars, thus highlighting the need to use a range of varieties in this kind of study. Copyright © 2009 Society of Chemical Industry  相似文献   

11.
12.
The effects of methyl jasmonate coupled with modified atmosphere packaging (MJ+MAP) on the quality and shelf life of mature green tomato ( Lycopersicon esculentum Mill.) were investigated during cold storage at 5 °C. Tomatoes were treated with 10−4  m MJ and packaged under 5%O2/5%CO2/90%N2 in a plastic bag. The effects of MJ+MAP were compared with control as well as heat treated (HT) samples. Control samples were tomatoes packaged under atmospheric air. HT samples were prepared by dipping tomatoes in hot water at 50 °C for 3 min and packaged under atmospheric air. The results showed that MJ+MAP and HT could delay ethylene production during tomato ripening and consequently slowed down the softening rate. MJ+MAP tomatoes showed better quality and less chilling injury (CI) symptoms than HT and control samples. Based on a nine-point score, shelf life criteria assumed that rejection would occur when the sensory attributes declined below 5. Control and HT overall acceptance scores were shown to fall below 5 scores after 3 and 6 weeks storage, while MJ+MAP had overall acceptance scores above 5 for up to 9 weeks. Control and HT samples could be stored for about 4 and 6 weeks, respectively, while MJ+MAP tomatoes could be stored for up to 9 weeks.  相似文献   

13.
Changes in the physicochemical and sensory characteristics of commercial plain (whole) and pitted ripe olives of the Gordal, Manzanilla, Hojiblanca and Cacereña cultivars were studied during a three‐year period in conditions that mimicking the storage of such products in real life. No spoilage was developed during this period. Throughout the shelf‐life, the pH of the cover brines had a marked valley decrease at the beginning of storage followed by a progressive further decline, the surface colour (measured instrumentally) and firmness of the olives followed a first‐order kinetic decay, mitigated according to the iron and calcium contents. Also, a slight browning of the cover brines at the beginning of the storage was observed. No significant changes in most of the sensory characteristics were observed by the panel test during shelf‐life except for a limited change in olive surface colour. At the end of the shelf‐life, most of the samples were classified as ‘extra’ category according to the IOC sensory evaluation method and only plain Gordal presentation was classified as ‘first, choice or select’.  相似文献   

14.
In this study, we have explored the relationship between the cultivation method and the concentration of major flavonoid aglycones, hydroxycinnamic acids, carotenoids and the total antioxidant activity of tomato (Lycopersicon esculentum cv Perfectpeel); in addition, we have investigated the bioactivity of polyphenol extracts from tomato. The main polyphenols in extracts were quercetin (33.90 ± 6.31 mg kg?1 and 17.92 ± 1.09 mg kg?1 in conventional and organic extracts), chlorogenic acid (3.52 ± 0.74 mg kg?1 and 2.82 ± 0.92 mg kg?1 in conventional and organic extracts) and caffeic acid (3.61 ± 0.71 mg kg?1 and 3.29 ± 0.33 mg kg?1 in conventional and organic extracts). Although statistical differences were found between organic and conventional extracts in several target compounds, no difference in biological effect was observed using cell models. The observed Trans Epithelial Electrical Resistance values were not significantly different between organic and conventional tomato extracts, but we have observed, in both samples, a decrease in tight‐junction permeability at 17 μm of polyphenol concentrations. Antioxidant compounds entering within the cell could exert an antioxidant action, nevertheless at concentrations >17 μm could have a pro‐oxidant effect.  相似文献   

15.
The effects of various post-harvest treatments on chemical changes, microbiological quality and occurrence of spoilage in ripe tomatoes (Lycopersicon esculentum L) were investigated. Fruits were pretreated in 70% ethanol or 0.2% benomyl before being packaged in low density polyethylene (LDPE), high density polyethylene (HDPE) or raffia palm basket. Fruit was stored at 27–32°C for up to 16 days. Control fruits (without pretreatment or packaging) showed the highest increase in pH; basket-packaged fruits were erratic but LDPE- and HDPE-packaged fruits showed gradual increases. Changes in titratable acidity were the inverse of those in pH. Among packagings, LDPE most effectively maintained total soluble solids (TSS) as compared with basket-packaged fruits, and the control showed the lowest TSS. Of the pretreatments, benomyl-treated fruits retained higher TSS. Aspergillus spp, Penicillium spp, Pseudomonas spp and Escherichia spp occurred most commonly in control and basket-packaged fruits, but Rhizopus spp and Leuconostoc spp predominantly occurred in LDPE- and HDPE-packaged fruits. Microbial load was lowest in benomyl-treated fruits followed by ethanol-treated and control fruits. Spoilage was higher (53.1%) in ethanol-treated than in benomyl-treated (43.8%) fruits.  相似文献   

16.
The objective of this study was to investigate if there were any differences in the physicochemical and sensory properties of organic and conventional potatoes (cv. Orla). The conventional potatoes had a lower dry matter content (P ≤ 0.05) and a slightly softer texture (P ≤ 0.05) than the organic potatoes. The trained panel perceived the conventional baked potato to be slightly softer, less adhesive and wetter than the organic baked potato (P ≤ 0.05). However, the consumer panel found no significant difference between the organic and conventional baked potato samples for the sensory attributes of appearance, aroma, texture and taste acceptability.  相似文献   

17.
Effect of germination time on comparative sprout quality characteristics (proximate composition, ascorbic acid, phytic acid, invitro protein digestibility, protein solubility and sensory properties) was investigated. Sprouting significantly increased (P<0.01) the moisture, crude protein, crude fat and ascorbic acid contents and decreased nitrogen free extract (NFE). Phytic acid was reduced (P<0.01) with sprouting, but more pronouncedly so in the case of Kabuli type (73% reduction) than in desi type (32% reduction). In-vitro protein digestibility (IVDP) and protein solubility improved significantly (P<0.01) with increase in sprouting time. The overall sensory scores increased with the first (24 h) sprouting interval and then decreased. However, the acceptability scores for both chickpea types remained within the acceptable range (>5.0). Although, organoleptically the desi type chickpea sprouts were preferred over Kabuli type, the nutritional improvement due to sprouting was more pronounced in Kabuli chickpeas than their desi counterparts. Due to overall superior sprout quality, the kabuli type was more suitable for sprouting purposes.  相似文献   

18.
The morphology, molecular structure and physicochemical properties of starches from two cultivars (NC8A97, Lath 96) of grass pea (Lathyrus sativus L.) were examined. In both cultivars, starch granules were irregular to oval to round to elliptical shaped, with smooth surfaces. No significant differences was observed between the cultivars with respect to mean granule diameter (26.3–27.3 μm), mean granule length (32–34.5 μm), amylose content (37.95–38.30%), bound lipid content (0.08%), amylopectin chain length distribution, average chain length (19.2) and X-ray diffraction pattern (‘C’ type). However, NC8A97 and Lath 96 starches differed significantly with respect to the degree of crystallinity (Lath 96 > NC8A97), B-polymorphic content (Lath 96 > NC8A97), granular swelling (NC8A97 > Lath 96), extent of amylose leaching (NC8A97 > Lath 96), peak viscosity (Lath 96 > NC8A97), shear stability (Lath 96 > NC8A97), set-back (NC8A97 > Lath 96) and susceptibility towards enzyme and acid hydrolysis (NC8A97 > Lath 96). The results showed that physicochemical properties of the grass pea starches were influenced by the extent of interaction between starch chains (Lath 96 > NC897) in the amorphous regions, amount of crystallites (NC8A97 > Lath 96) and crystallite heterogeneity (NC8A97 > Lath 96).  相似文献   

19.
Reduced-fat stirred yoghurts were prepared by using ropy and nonropy exopolysaccharide (EPS)-producing strains or nonexopolysaccharide-producing strains. Yoghurts were evaluated for pH, titrable acidity, acetaldehyde, whey separation, viscosity, EPS concentration, sensory and microbiological analyses. Determinations of these parameters were made at 1, 7, 14 and 21 days of storage. Reduced-fat yoghurts made with EPS+ strains exhibited lower syneresis and acetaldehyde contents, but higher viscosity than those made with the EPS strain. Physico-chemical results correlated with the sensory results in that panellists scored the EPS+ yoghurts as having an overall better mouthfeel, but a worse flavour than EPS yoghurt.  相似文献   

20.
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