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1.
    
The essential oil of wild Daucus carota L. from Corsica was investigated by GC and 13C‐NMR spectroscopy. In a first part, a commercial sample was repeatedly chromatographed and the analysis of the fractions led to the identification of 69 components. The oil consisted chiefly of phenylpropanoids (45.9%) and monoterpene hydrocarbons (38.6%), with (E)‐methylisoeugenol (33.0%), α‐pinene (24.9%) and elemicin (11.4%) as major components. The second part concerned the analysis of laboratory‐distilled oils obtained from different parts of the plant at three stages of development (prior flowering, full flowering and end of flowering). The chemical composition of the Corsican wild carrot oil varies according to its stage of development. The oil yields, as well as the phenylpropanoid contents, particularly that of (E)‐methylisoeugenol, increase significantly when the umbels ripen. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

2.
    
BACKGROUND: The aim of the study was to investigate the effects of variety, soil type and fertilisation, and the interactions between these factors, on yield and quality traits of carrots. RESULTS: Optimum fertilisation levels for yield and quality of grade one roots were found to be between 80 and 160 kg ha?1 for nitrogen and between 0 and 120 kg ha?1 for potassium depending on soil type and precipitation. Carrots grown in peat soil had the highest score for sweetness and the lowest scores for negatively associated characteristics such as bitterness, earthy flavour, terpene flavour and firmness. Nitrate content and the amounts of splitted and forked roots were lowest on sandy soil. Variety significantly affected number of grade 1 roots, dry matter, nitrate content and most of the sensory attributes tested. Interactions between variety, soil type and nitrogen fertilisation were found for most of the tested quality characteristics. CONCLUSION: The investigations showed that year and variety had the highest impact on the carrot quality attributes studied, whereas soil type and fertilisation had less influence. Peat soil and moderate fertilisation with N and K gave optimal sensory quality while sand soil gave optimal quality as regards morphological characters like splitting and forking of roots as well as nitrate content. Copyright © 2012 Society of Chemical Industry  相似文献   

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The combined effect of emerging electro-technology high-voltage cold plasma (HVCP) and non-thermal ultra-high hydrostatic pressure (UHP) as bioprocess technologies on the quality and stability of carrot juice has been evaluated. Carrot juice was treated with HVCP (70 kV for 3 min), UHP (300, 400, and 500 MPa) at 25 °C for 5 min, and a blanched sample of 100 °C for 5 min (BS) was also prepared. As compared to control and single treatments, the combined treatment (HVCP-UHP500) has attained better results in terms of enzyme inactivation and electroporation extraction of coloring compounds, phytochemicals, and ascorbic acid. Wherein, the maximum of 25.87 ± 0.12a µg/100 mL of β-Carotene, 11.89 ± 0.80a GAE (µg g−1) of total phenols, and 24.07 ± 0.12b mg/100 mL of ascorbic acid content in carrot juice were also observed in the combined treatment at 500 MPa. In addition, phytochemical enhancement might be attributed to the disintegration of phenolic dimers into simple aglycones, predominantly because of the electro-kinetic phenomenon of HVCP, which is subsequently intensified by UHP treatment. Therefore, the current study suggests that the combination of two novel techniques is a highly efficient method in terms of energy, time, and cost, with low yield efficiency and bio-safety.  相似文献   

5.
Quantitative analyses of volatile compounds isolated from raw carrots were combined with sensory analysis in order to identify the role of these compounds on aroma and flavour perception in coloured carrots. A sensory map of carrots with different colours was developed, the content of the isolated volatiles was determined and the role of these compounds for harsh flavour perception in raw coloured carrots was evaluated using multivariate data analysis. The sensory map showed that the coloured carrots formed distinct groups within the sensory profile. The orange genotypes were characterised by having significantly higher intensities in carrot flavour and aroma, while the reverse was true for the yellow genotypes. The purple genotype was characterised by having significantly higher intensity in sickenly sweet flavour and nutty flavour, and the red genotype was characterised by having significantly higher intensities in green aroma and flavour, bitterness and burning aftertaste. From the multivariate data analysis it was concluded that the isolated terpenes do correlate to the harsh flavour attributes.  相似文献   

6.
    
The current study focused on the valorization of carrot leaves, Daucus carota L. because of their high amount of ascorbic acid (AA), phenolic compounds, and the related antioxidant activity. In this study, the changes in carrot leaves caused by different drying techniques (freeze, vacuum, microwave-assisted infrared, oven) and different storage conditions (room temperature and refrigerator) were investigated. AA contents of fresh, dried, and stored carrot leaf samples were chromatographically determined. Additionally, analysis of TPA (total phenolic content), TAC (total antioxidant capacity), total chlorophyll, carotenoid, and color were carried out. Additionally, fresh leaves were analyzed to compare their results with the corresponding values of processed or stored samples. TPA, TAC, AA, total chlorophyll, and carotenoid values of the samples stored in the refrigerator were 889 ± 63 mg/100 g d.b., 504 mg/100 g d.b., 269 A.A./100 g d.b., 253 mg/100 g d.b., and 2497 mg/100 g d.b., respectively, while the values of the samples dried at room temperature 620 ± 35 mg/100 g d.b., 303 ± 15 mg/100 g d.b., 110 ± 21 mg A.A./100 g d.b., 44 ± 3 mg/100 g d.b., 641 ± 16 mg/100 g d.b., respectively. Consequently, fresh carrot leaves have a higher vitamin C content than many leafy vegetables and even its own family, parsley. Fresh samples stored at room temperature and in the refrigerator for 7 days provided high ascorbic acid retention. Dried leaves with the MW + IR combined system provided better protection than others in terms of bioactive components. However, OD treatment at 40°C provided better protection and was one step ahead in terms of AA content.  相似文献   

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Monoterpenes are plant‐based alternatives for pest control in sustainable agriculture. This study investigated the phytotoxic effects of the monoterpene limonene on white cabbage (cv Rinda and Lennox) and carrot (cv Parano and Splendid) plants. The effects of increasing concentrations (from 10 to 120 ml l?1) of limonene on visible leaf injuries, growth, chlorophyll fluorescence, net photosynthesis and stomatal conductance were studied. Limonene concentrations of 90 and 120 ml l?1 were significantly phytotoxic in both cabbage and carrot, depending on the cultivar. However, there were major differences in limonene responses between the cultivars in both species. In carrot, lower shoot and root biomass was related to lower chlorophyll fluorescence (indicating lower efficiency of the photochemical processes) in cv Splendid, whereas in cv Parano it was related to lower stomatal conductance (indicating reduced gas exchange), suggesting that the mechanism behind the phytotoxicity may be different in different cultivars. In cabbage, better limonene tolerance and faster recovery processes in cv Lennox compared with cv Rinda were evident through increasing efficiency of photochemistry (chlorophyll fluorescence), and in the higher stomatal conductance and net photosynthesis rates, providing energy for defence and repair action. Since direct phytotoxic effects were detected on carrot and cabbage with limonene, we conclude that critical threshold concentrations for cultivated plants should be determined before monoterpenes are widely used as repellents and deterrents. These thresholds should, as far as possible, be species‐ and cultivar‐specific in order to provide full protection of plants. Copyright © 2004 Society of Chemical Industry  相似文献   

8.
研究微波提取对胡萝卜中的多糖基本结构特征及固体形貌的影响。采用沸水浴、微波两种方式提取胡萝卜中的多糖(分别记为WEP和MEP),通过基本理化性质测定、高效体积排阻色谱(high performance size exclusion chromatography,HPSEC)和单糖组成分析等方法比较了两者的基本结构特征,并采用扫描电子显微镜对两者的固体形貌进行表征。结果显示,WEP和MEP的中性糖、糖醛酸和总酚含量存在差异,两者均由半乳糖醛酸、半乳糖、葡萄糖、阿拉伯糖、鼠李糖组成,但MEP总糖含量更高并含有更多果胶类单糖;WEP和MEP的HPSEC图有一定相似性,但WEP中含有重均分子质量高达7.77×105 D的组分;WEP表现较为聚集的片状结构,而MEP组分则表现较为分散且主要为小片段状态。上述结果表明,两种不同提取方法所得到的多糖具有显著差异。  相似文献   

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The chemical composition of carrot umbel oils obtained by hydrodistillation of three cultivars of Daucus carota L. ssp. sativus was investigated by GC and GC–MS. Forty components were identified. The oils were dominated by monoterpene hydrocarbons (66–85%) represented mainly by α‐pinene (40–46%) and myrcene (12–24%). The most abundant sesquiterpene constituents were β‐caryrophyllene (4.6–13.2%) and carotol (1.2–6.1%). Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

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BACKGROUND: The demand for organic food products has increased during the last decades due to their probable health effects, among others. A higher content of secondary metabolites such as carotenoids in organic food products has been claimed, though not documented, to contribute to increased health effects of organic foods. The aim was to study the impact of organic and conventional agricultural systems on the content of carotenoids in carrots and human diets. In addition, a human cross‐over study was performed, measuring the plasma status of carotenoids in humans consuming diets made from crops from these agricultural systems. RESULTS: The content of carotenoids in carrot roots and human diets was not significantly affected by the agricultural production system or year, despite differences in fertilisation strategy and levels. The plasma status of carotenoids increased significantly after consumption of the organic and conventional diets, but no systematic differences between the agricultural production systems were observed. CONCLUSION: The expected higher content of presumed health‐promoting carotenoids in organic food products was not documented in this study. Copyright © 2011 Society of Chemical Industry  相似文献   

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Carrots, a globally cultivated root vegetable crop, are renowned for their nutritional and functional properties. However, the deep utilization and development of carrots and their derived products are limited in numerous countries, with a particular deficiency in advanced deep-processing and transformation technologies. Consequently, the value of carrot products is diminished and resources are wasted. This review explores the nutritional value and characteristics of different carrot varieties, providing a comprehensive overview of the current state of carrot product processing. These products include primary processed products such as minimally processed carrots, dried carrots, pickles, preserves, fruit purees, yoghurt, juice, and essential oils, as well as processed by-products including functional phytochemical extractions such as carotenoids, polyphenols, dietary fibers, active peptides, and glycoproteins. This review also covers other by-products, including feeds, fast food boxes, and bioethanol production. Furthermore, cutting-edge technologies related to carrot processing are discussed. The ultimate goal of this review is to provide researchers and practitioners with an in-depth understanding of the present status of carrot production.  相似文献   

12.
人参与胡萝卜愈伤组织共培养的研究   总被引:1,自引:0,他引:1  
杨晶  张美萍  王义 《食品科学》2008,29(1):55-59
本研究采用正交试验设计,对人参(Panax ginseng)和胡萝卜(Daucus carota)两种植物组织共培养的培养基和培养条件进行了优化筛选,同时比较了人参愈伤组织与共培养物的皂苷含量.结果表明,人参与胡萝卜共培养所获得的愈伤组织在23℃,10001x的条件下生长良好,最佳基质MS 2,4-D 3mg/L IBA 2mg/L KT 0.5mg/L,在培养25d时皂苷含量达到最高,浓度达到1.6mg/L.共培养物的皂苷含量比人参愈伤组织皂苷含量高出6.25%,为人参与胡萝卜原生质体融合、获得营养型蔬菜奠定了基础.  相似文献   

13.
    
Browning index, degree of browning, total phenolics content and polyphenoloxidase (PPO) activity of three carrot cultivars—Kendo, Ricardo and Stefano—were studied on a simulated market shelf (20 °C) and during cold storage (4 °C). There was a general increase in browning indices and degree of browning during simulated marketing storage for all three cultivars. The three cultivars had similar levels of browning after cold storage but Ricardo reached the highest level after 10 days of simulated shelf life. There appeared to be a rapid increase in total phenolics content during cold storage, which increased further during a simulated marketing trial. The PPO activities of Kendo and Stefano decreased during cold storage whereas that of Ricardo increased, reaching its highest level after 2 months in cold storage. A positive and significant correlation between total phenolics and degree of browning was found for all three cultivars stored for different lengths of time. This research suggests that shorter periods of cold storage reduce the potential for carrot browning and hence prolong the shelf life of carrots. Copyright © 2004 Society of Chemical Industry  相似文献   

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Carrot seed was extracted with the solvents 1,1,2-trichloro-1,2,2-trifluoroethane (TTE), methylfuran (sylvan), ethanol and dichloromethane. After evaporation of the solvent, the resinoids obtained were steam distilled to separate the volatile components. The chemical composition of the essential oil samples obtained using the different solvents, as well as that obtained by hydrodistillation, were compared. Quantitatively, the highest yields of concrete and essential oil were obtained using sylvan (4.79% and 0.47%) and ethanol (3.30% and 0.87%). These yields of essential oil are greater than those obtained by hydrodistillation (0.40%). Some of principal components varied in amount with the extraction solvent used. For example, GC-MS analysis showed that the contents of α-pinene were 2.47% (sylvan), 0.25% (TTE), 0.30% (EtOH), trace (CH2Cl2) and 13.31% (hydrodistillation). Those of geranyl acetate were (the same order as above) 23.58%, 3.48%, 12.08%, 10.11%, and 10.39% and those of carotol were 13.97%, 40.91, 39.06%, 31.75%, and 18.29% respectively.  相似文献   

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ABSTRACT:  The color of aqueous solutions obtained by heating carrot ( Daucus carota L.) roots in water (\"stocks\") is different when the thermal treatment is applied with or without exposure to light. CIE L *, a *, and b * scale values of stocks processed for different times were recorded and 4 patterns were initially observed. To explain the 1st part of this evolution (patterns 1 and 2), pectin extraction and β-elimination in stocks were studied. Light dependence was investigated to explain patterns 3 and 4. A model with 2 compounds is proposed to explain all the color variations.  相似文献   

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The essential oils from leaves and seeds of some angiosperms collected from different localities of Varanasi as well as from local markets were tested against the mycelial growth of Aspergillus flavus. Amongst them the volatile oil from seeds of Daucus carota L. exhibited absolute toxicity against the test fungus. The minimum inhibitory concentration of the oil at which it exhibited fungistasis was 2000 ppm when it was not phytotoxic on seed germination and seedling growth of guar, Cyamopsis tetragonoloba L. (Taub.). It exhibited a broad fungitoxic spectrum inhibiting the mycelial growth of a number of fungi at 1500, 2000 and 2500 ppm. Moreover, the oil was more effective than some synthetic fungicides including Agrosan G.N., copper oxychloride, Derosal, Dithane M-45 and Thiovit.  相似文献   

17.
R. G. Klaiber    S. Baur    L. Magel    W. P. Hammes    R. Carle 《Journal of food science》2004,69(4):SNQ161-SNQ16
ABSTRACT: Different washing treatments with chlorinated and ozonated water were applied to carrots ( Daucus carota L.) on an industrial scale to improve the sensorial and microbial quality of packaged ready-to-eat produce. Quality of shredded carrots was determined by sensory evaluation and microbiological analysis. Washing shredded carrots resulted in increased sugar leaching and loss of sensorial quality, whereas prewashing uncut carrots with chlorine ensured sugar retention, reduced microbial load, and concurrently minimized cross-contamination. Comparable germ reduction was not achieved by prewashing with ozone. These findings demonstrated that prewashing uncut carrots with chlorine provided sufficient microbiological safety paired with improved sensorial properties.  相似文献   

18.
  总被引:1,自引:0,他引:1  
ABSTRACT: Callus cultures of carrot, Nentes scarlet - 104 variety, were initiated on MS medium for anthocyanin production. Two anthocyanins, cayanidin-3-lathyroside and cyanidin-3-glucoside, PRESENT in the ratio of 3:1, were identified in the callus cultures. Eight sugars were tried as carbon source for the production of total anthocyanin. The sugars xylose and lactose, although they initiated growth of the green callus, did not initiate anthocyanin pigmentation. Fructose, galactose, and maltose produced less than 1.75% (dry weight basis) anthocyanin though there was growth of the pigmented callus. Glucose and sucrose produced 3.5%. It was observed that 7.5% sucrose in the medium produced maximum amount of anthocyanin (6.5%). Total nitrogen at 70 mM concentration and a 1:4 ratio of ammonium to nitrate yielded maximum cell growth and best anthocyanin production. Modifying the medium it was possible to enhance the production to 6-8%.  相似文献   

19.
王义  杨晶  孙春玉  杨忠  张美萍 《食品科学》2008,29(2):126-129
本实验对人参(Panax ginseng)和胡萝卜(Daucus carota)两种植物组织进行悬浮混合培养,筛选出悬浮混合培养的最佳培养基.同时对人参愈伤组织、胡萝卜愈伤组织及其混合培养物的代谢产物进行了研究.结果表明,人参与胡萝卜悬浮混合培养的最佳基质为MS、2,4-D 2mg/L、NAA 1mg/L、KT 0.2mg/L,在培养25d时混合培养物的多糖含量达到最高,浓度达到0.203mg/g,混合培养物的皂苷含量为1.85mg/g,比人参悬浮培养物皂苷含量高出3.35%.  相似文献   

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