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1.
BACKGROUND: Supplying egg‐laying hens with different forage materials may influence egg production and quality. The aim of this study was to examine the short‐term effects of standard feed plus 70 g day?1 per hen of three coloured carrot varieties (orange, yellow and purple) as forage material in comparison with a standard feed control on egg production, egg yolk colour and deposition of carotenoids in the yolk. RESULTS: Carrot supplementation reduced feed intakes significantly, but not on a dry matter basis. Orange carrot treatment significantly reduced egg mass production, whereas yellow and purple carrot treatments did not differ from the control. Egg and yolk weights of all carrot‐supplemented treatments were significantly lower than those of the control, but yolk percentages were similar. Yolk redness increased significantly in the order control < yellow < orange < purple. A similar trend was seen for yolk yellowness, but yellow and orange carrots reached the same level. Yolk colour and carotenoid contents correlated positively and significantly. In particular, purple carrot treatment increased the yolk content of lutein (>1.5‐fold) and β‐carotene (>100‐fold) compared with the control. CONCLUSION: Supplementing the feed of egg‐laying hens with coloured carrots efficiently increased yolk colour parameters and carotenoid contents, which gives opportunities for improved nutritional value of eggs from forage material‐supplemented hens. Copyright © 2010 Society of Chemical Industry  相似文献   

2.
BACKGROUND: Organic food is perceived as being of better quality and healthier than conventional foods although the scientific research on organic foodstuffs is highly contradictory. The aim of the present study was to investigate if intake of carrots from four different cultivation systems grown in two consecutive years would influence various biomarkers of health in a rat model. All rats were fed a diet with 40% carrot content. The carrots were grown under conventional (C), ‘minimalistic’ organic (O1), organic (O2), or ‘very’ organic cultivation systems (O3). A control group (CO) being fed standard rat chow was included. RESULTS: The plasma α‐tocopherol concentration was higher in the O2 carrot‐based diet group than in the C carrot based‐diet group in one year, while all other health biomarkers or nutrient content differences were observed between the CO diet and the carrot‐based diets. CONCLUSION: This well‐controlled field study demonstrated no clear influence of cultivation methods or harvest year on the nutritional quality of carrots or effect of cultivation methods on health‐related biomarkers in a sensitive rat model. However, the experimental set‐up and selected biomarkers could be used as a framework for further studies of health in relation to organic foodstuff. Copyright © 2012 Society of Chemical Industry  相似文献   

3.
《Food chemistry》2005,89(1):69-76
Ready-to-eat shredded orange and purple carrots, packed in air (control), or in modified atmosphere packaging [MAP; (90%N2 + 5%O2 + 5%CO2 and 95%O2 + 5%CO2)], and stored chilled for up to 13 days, were examined for their antioxidant activity and contents of anthocyanins, carotenoids and phenolics, as well as sensory quality. Total antioxidant activity, carotenoids and phenolics of purple carrots were initially 2.8-, 2.3- and 2.9-fold higher than orange carrots, respectively. Total antioxidant activity remained relatively constant in orange carrots during storage under all treatment conditions, whereas a highly significant decrease (P<0.01) in (95%O2 + 5%CO2)-treated purple carrots was observed. The content of anthocyanin, only found in purple carrots, was decreased slightly during the storage period, and this was particularly significant in the 95%O2 + 5%CO2 treatment. In both orange and purple carrots, loss of total carotenoids occurred in the 95%O2 + 5%CO2 treatment. Total phenolic content of purple carrots increased at a much higher rate during storage than orange carrots. The MAP treatment (90%N2 + 5%O2 + 5%CO2) gave better sensory quality and extended shelf-life for purple carrots (∼2–3 days longer shelf-life than other treatments,) but, no difference was observed for orange carrots. Shredded purple carrot can be stored under 90%N2 + 5%CO2 + 5%O2 treatment for up to 10 days and high nitrogen treatment may be used in maintaining the storage quality of shredded purple carrots. Thus, purple carrots may be used in place of orange carrots to take advantage of their nutraceutical components.  相似文献   

4.
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   

5.
The application of high pressure processing (HPP) has shown its potential to reduce quality losses of many fruit and vegetable products in comparison to other traditional technologies such as cooking. To identify further opportunities of the application of high pressures in vegetable pieces, the sensory perception and correlation to quality parameters were investigated on carrot sticks (used as model product) submitted to high pressure treatments (600 MPa, 2 min) and compared to other traditional treatments such as sous-vide (90 °C, 5 min), cooked (100 °C, 20 min) and unprocessed (raw). The results indicated that HPP carrots were not different from sous-vide carrots in many parameters such as: sweetness, green flavour and crunchy texture. Furthermore, high pressure carrots showed significantly higher intensity perception of orange colour and fibrousnesses to the rest of the treatments, while similar brightness to cooked carrots and green odour to raw.Throughout 14 days of storage at 4 °C, there was clear evidence that HPP samples could be preserved better in comparison to the rest of the treatments by not presenting any production of acetic acid (used as quality deterioration reference).Overall, sensory evaluation showed correlations to many quality measurements in this study, indicating similarities in hardness versus crunchiness perception and juiciness versus moisture perception between HPP and sous-vide samples. GC/MS and GC/MS-O results were also in agreement in most cases when identifying carrot volatile changes between the different treatments and the identification of the development of new compounds formed.Finally, the tissue structure observed by using Cryo-SEM microscopy, supported the similarities (between HPP and sous-vide) and differences (between treatments) of the quality parameters analysed in this research.

Industrial Relevance

Previous reports on HPP for food applications indicated that this technology will only be commercially successful if added value is achieved or if the product characteristic can be retained at a higher level as compared to thermally/traditionally processed foods. This work provides information on textural and chemical (volatile) changes as well as the sensorial perception of carrots which have undergone high pressure processing, as well as how those changes compare to the quality of both raw and thermally processed carrots. These results may be generally applicable to what could be expected to happen to other ‘hard’ tissue vegetable products produced by high pressure processing, over a refrigerated storage time of 14 days.  相似文献   

6.
Purple carrot was analysed for its antioxidant activity by measuring its scavenging effect on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical. The amount of purple carrot necessary to decrease by 50% the initial DPPH concentration (EC50) was found 30.23 +/- 5.17 (mg sample/mg DPPH). Effects of the dehydration process on the antioxidant activity of purple carrots were also determined after dehydration by using tray drier and microwave+tray drier combination. Purple carrots were cleaned, washed, sorted, sliced, and blanched in water at 98 +/- 1 degree C for 2 min. Then half of the samples were dehydrated in microwave (45 min) and tray drier (105 min) combination, and others were dehydrated in tray drier (150 min) until reaching the constant weight. Raw, blanched and dehydrated purple carrots were compared for their antioxidant activity and total anthocyanin contents, color values (L*, a*, b*, C*, H degrees) and dry matter contents. The antioxidant activity as measured by DPPH, EC50 value ranged from 7.80 to 30.23 of processed and raw carrots where the H degrees values were changed from -3.68 to -23.96 corresponding to a bluish hue.  相似文献   

7.
The concentration‐dependent activity of the polyacetylene falcarinol ((9Z)‐heptadeca‐1,9‐dien‐4,6‐diyn‐3‐ol), isolated from carrots, was investigated in a bioassay with primary mammary epithelial cells in collagen gels and compared with that of β‐carotene, the orange pigment in carrots. Falcarinol showed biphasic activity, having stimulatory effects between 0.01 and 0.05 µg ml?1 and inhibitory effects between 1 and 10 µg ml?1, whereas β‐carotene showed no effect in the concentration range 0.001–100 µg ml?1. The results are discussed in relation to the health‐promoting effects of carrots and related vegetables. Falcarinol was quantified in the carrot cultivars Bolero, Rodelika and Fancy by analytical reverse phase HPLC, subjected to various processing and storage conditions in order to study how long‐term storage, blanching, freezing and boiling influence the content of falcarinol. Long‐term storage of raw carrot cubes (1 cm3) reduced the falcarinol content by almost 35%. A similar reduction was found in steam‐blanched carrot cubes (1 cm3). Long‐term storage at ?24 °C of steam blanched carrot cubes did not reduce the falcarinol content further. A reduction of almost 70% in the falcarinol content was found in carrot pieces boiled in water for 12 min compared with raw carrots. Copyright © 2003 Society of Chemical Industry  相似文献   

8.
Long term alcohol consumption is one of the important causes for liver failure and death. To complicate the existing problem there are no dependable hepatoprotective drugs and a large number of patients prefer using complementary and alternative medicines for treating and managing hepatic complications. Almost 25 centuries ago, Hippocrates, the father of medicine, proclaimed "Let food be thy medicine and medicine be thy food." Exploring the association between diet and health continues even today. Preclinical studies carried out in the recent past have shown that the commonly used dietary agents like Allium sativum (garlic), Camellia sinensis (tea), Curcuma longa (turmeric), Emblica officinalis (Indian gooseberry), Ferula asafoetida (asafoetida), Garcinia cambogia (Malabar tamarind), Glycine max (soyabean), Murraya koenigii (curry leaves), Piper betle (beetle leaf), Prunus armeniaca (apricot), Ocimum gratissimum (wild basil), Theobroma cacao (cocoa), Trigonella foenum-graecum (fenugreek) and Vitis vinifera (grapes) protect against ethanol-induced hepatotoxicity. Mechanistic studies have shown that the beneficial effects of these phytochemicals in preventing the ethanol-induced hepatotoxicity are mediated by the antioxidant, free radical scavenging, anti-inflammatory and anti-fibrotic effects. The present review for the first time collates the hepatoprotective effects of these agents and also emphasizes on aspects that need future research to establish their utility in humans.  相似文献   

9.
The release and absorption (bioavailability) of carotenoids is a prerequisite for their nutritional impact. This can be strongly affected by the processing conditions used to prepare the food matrix that contains them. To determine the effect of processing on carotenoid bioavailability, homogenized, raw, blanched and cooked carrots were exposed to an in vitro gastric and intestinal digestion model. Final digest samples were placed onto a Caco-2 cell trans-well monolayer culture to mimic intestinal absorption. The results show that the cooked carrot puree consisting of primarily single plant cell particles had the highest release of carotenes, followed by blanched consisting primarily of plant cell clusters and raw carrot puree consisting of larger plant cell clusters. Absorption through the Caco-2 cell layer was the highest from the digesta of cooked carrot puree followed by the digesta of blanched carrot puree. This study demonstrates that thermal processing and/or mechanical homogenization to disrupt plant cell wall matrix enhances the in vitro bioavailability of carotenes from carrots.  相似文献   

10.
以盐酸萘乙二胺法测定了桃、黄皮、橄榄、柑皮、柑、豆角、萝卜的腌制样品和新鲜样品中NO2-的含量.结果表明,其中陈皮(即柑皮制品)的NO2-的含量最高,萝卜的腌制样品和新鲜样品中的NO2-含量相差不大,黄皮的新鲜样中NO2-的量比腌制品高,并模拟洗涤、腌制工序,分别以柑皮和萝卜为例,测前后NO2-量的变化程度.  相似文献   

11.
Vitamin A deficiency remains a public health problem in the developing world. The highest prevalence of vitamin A deficiency is in Africa and Asia (>30%). Dietary modification, a long‐term strategy to address vitamin A deficiency, complements food fortification and vitamin A supplementation programmes. Provitamin A carotenoids from foods of plant origin are more affordable than preformed vitamin A from animal foods, and many resource‐poor households rely on yellow/orange‐fleshed vegetables and fruits and dark‐green leafy vegetables as their main source of vitamin A. The provitamin A carotenoid content in plant foods varies widely and differences among cultivars of the same food exist. Several factors influence the bioavailability of provitamin A carotenoids. The potential contribution of plant foods to vitamin A status depends on the retention of provitamin A carotenoids after storage, preparation and processing. Home‐gardens can provide households with direct access to provitamin A‐rich vegetables that are not readily available or within their financial reach. The components and critical issues of home‐garden projects are described. Copyright © 2006 Society of Chemical Industry  相似文献   

12.
The dietary fibre (DF) content of some storage-strong vegetables, grown in Norway, has been determined. The vegetables were collected at harvest time and at intervals during storage, to monitor the DF content during the storage season.Nantes, a variety of carrot, and Hygro, an onion variety, were available throughout the entire period of investigation. A slight decrease in the DF content with length of storage was observed for carrots, but not for onions.With cabbage (Golden Acre, Toten Amager and Blue Top varieties) and rutabaga (Gry and Bangholm varieties) any particular variety was available only for a shorter period (1–4 months), with little overlap between varieties. No systematic change in DF content was observed within any variety during this period. However, differences in DF content from variety to variety within the same vegetable were found.The observed DF variations within each vegetable, whether due to storage or to variety, were relatively slight and need not normally be taken into account when estimating the DF contents of diets containing these vegetables. Some methodological problems are discussed.  相似文献   

13.
Abstract Blond orange juice was colored with black carrot concentrate as an alternative to blood orange juice. Thermal stability of anthocyanins from black carrots in orange juice was determined at 70, 80 and 90C. Anthocyanin degradation in colored blond orange juice followed to first-order reaction kinetics. As expected, the degradation rate was dependent on temperature, being faster at higher temperatures. Half-lives for anthocyanin degradation were 12.5, 6.3 and 3.1 h at 70, 80 and 90C, respectively. Between 70–90C, activation energy was 72.03 kJ mol-1. Results showed that coloring blond orange juice with black carrot concentrate resulted in a much more stable product as compared with blood orange juice.  相似文献   

14.
The colour of the background on which products are presented may affect their perceived attractiveness. In order to find out on which type of background various fresh food products look most attractive, we presented five different vegetables (tomato, carrot, yellow bell pepper, eggplant, mushroom) on five different backgrounds with neutral grey colours varying in degree of blackness: 5, 30, 50, 65, and 90%. Forty-six participants provided colour matches for the vegetables and evaluated them on 10 attributes.Overall, the blackness of the backgrounds had little or no effect on the perceived colour of the vegetable. Only for carrots we found a small but significant difference, mainly between the 5% and 90% blackness backgrounds. On the darkest background, the carrot would be perceived as a bit lighter, more saturated, and more yellow rather than red, compared to the lightest background.Differences in perceived attractiveness on the grey backgrounds varied between 0.3 and 1.0 units on a 9-point scale. Attractiveness and expensiveness ratings for most vegetables were highest on the 90% blackness background. In comparison to our previous study where we presented vegetables on hued backgrounds, differences between mean attractiveness ratings were smaller. Because mean attractiveness ratings in the current study were higher, we expect that grey backgrounds are more likely to present vegetable assortments with a variety of hues in an attractive way than hued backgrounds.  相似文献   

15.
Alternaria alternata and Alternaria radicina are fungal species that occur in several food crops and may produce mycotoxins and phytotoxins. The toxigenic profile of A. alternata and A. radicina isolated from carrot and other umbelliferous plants was determined by growing the fungus on rice and carrot discs. Most of the tested isolates of A. alternata produced the mycotoxins tenuazonic acid, alternariol, alternariol methyl ether and altertoxin-I on rice. Only alternariol and alternariol methyl ether were produced on carrot discs. When cultured on rice, none of the isolates of A. alternata from umbelliferous plants produced AAL toxins and fumonisins. AAL toxins, but not fumonisins, were instead produced by A. alternata f. sp. lycopersici isolate NRRL 18822 isolated from tomato. A. radicina produced the phytotoxic compounds radicinin, epi-radicinol and radicinol on carrot discs, whereas it produced radicinin and radicinol on rice. Although A. alternata has been frequently found in organic carrots, none of the above mycotoxins was detected in carrot roots or in carrot commercial products. The reduction of alternariol and alternariol methyl ether during carrot juice processing at laboratory scale was estimated to be >98%. Based on these findings and previous reports, it can be concluded that Alternaria mycotoxins in carrots do not represent a hazard for consumers.  相似文献   

16.
Alpha-, beta, and gamma-carotenes, β-cryptoxanthin and total vitamin A activity in five different immature cultivars of peppers (Cupsicum annuum), commonly consumed in the Northwest region of Mexico, were determinated by high performance liquid chromatography (HPLC). Among the cultivars studied, “Poblano” pepper had the highest provitamin A (111.4±28.2 μg Retinol Equivalents (RE)/100g) followed by “Serrano” (86.7 ±13.0), “Jalapeño” (67.0±8.7), “Verde” (30.2±3.0), and “Caribe” (2.2 ± 0.9). In general, these values were higher than the vitamin A of peppers reported by the Mexican food composition tables and lower than the data presented in the INCAP/ICNND food composition tables for USC in Latin America.  相似文献   

17.
Saleh NT  Ahmed ZS 《Meat science》1998,50(3):285-293
Eight ground beef patty formulations, based on replacing meat with a natural source rich in provitamin A (i.e.carrot and sweet potato) were prepared. All treatments displayed better moisture retention than the controls and hence yield was improved. L, a, and b Hunter values increased and Instron texture profile analysis indicated lower peak forces, increased springiness, and, in some cases cohesiveness (i.e. juicier patties) for formulalions with boiled carrot or sweet potato. However, adding these ingredients in a dry form increased hardness, springiness and cohesiveness. Improvement in the content of provitamin A was achieved by incorporating carrot or sweet potato into the patties. Mixing meat with a natural rich source of provitamin A could be a long-term solution for combating vitamin A deficiency.  相似文献   

18.
Alpha and beta carotene, provitamin A activity, dehydroascorbic acid, L-ascorbic acid and total ascorbic acid content of “jalapeño,”“bell,” long green/red “chile,”“serrano” and “yellow wax” peppers (Cupsicum annuum L.) at green and red stages of maturity were determined by HPLC. Effects of thermal processing on vitamin A and C retention in “jalapeno” peppers was also determined. Provitamin A activity ranged from 27.3 to 501.9 Retinol Equivalents (RE/100g). Ascorbic acid concentration ranged from 76.1 to 243.1 (mg/100g). Provitamin A activity and ascorbic acid content increased with maturity in all cultivars. Thermal processing of “jalapeño” cultivars resulted in a 25% decrease of total provitamin A activity and a 75% decrease in total ascrobic acid.  相似文献   

19.
以不同质量浓度的维生素C为阳性对照,研究鲜榨紫色胡萝卜汁体外抗氧化活性,并与橙色胡萝卜汁和白色萝卜汁做对比。分别采用Folin-酚法和pH示差法测定了紫色胡萝卜汁的花青素含量和总酚含量。结果表明,紫色胡萝卜汁体外对·OH、H2O2、O2-·具有较高的清除率,橙色胡萝卜汁和白萝卜汁对·OH、H2O2的清除率较紫色胡萝卜汁低,且对O2-·几乎无清除作用。鲜榨紫色胡萝卜汁中总酚含量23.90 mg/mL,花青素含量287.62 mg/L。0.1 mL稀释5倍的紫色胡萝卜汁对·OH的清除率为50.74%,相当于质量浓度为3 100 mg/L的维生素C对·OH的清除率;0.5 mL稀释15倍的紫色胡萝卜汁对H2O2的清除率为56%,相当于700 mg/L维生素C的清除率;1.5 mL稀释20倍的紫色胡萝卜汁对O2-·的清除率为51.85%,相当于40 mg/L维生素C对O2-·的清除率。  相似文献   

20.
Vitamin A deficiency is a public health issue in developing countries and promoting dietary carotenoids as precursors is a promising strategy. However, carotenoids present in numerous fruits and vegetables are unstable and poorly bioaccessible. This study evaluated these two parameters during in vitro digestion of carotenoids and retinoids from carrot juice, raw and cooked spinach, micronutrient-fortified flour and standards without food matrix. Standards were unstable whereas vitamin A from fortified flour and native food carotenoids were generally better protected by the food matrix (30–100% remaining versus 7–30% for standards). Hydrothermal cooking did not influence spinach carotenoid digestive stability but decreased their contents, phenomenon compensated by a significantly better micellarisation from 15-fold for β-carotene to 72-fold for lutein. Finally, carrot juice provided the greatest amount of bioaccessible provitamin A with 1850 μg/100 g dry matter (DM) versus 790 and 80 μg/100 g DM in cooked and raw spinach, respectively.  相似文献   

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