In vitro and in vivo effects of carrot on human blood platelet aggregation

Carrots are a good source of essential nutrients and bioactive phytochemicals including carotenoids, phenolic compounds and polyacetylenes such as falcarinol. In this study, we investigated the inhibitory effect of a carrot extract on blood platelet aggregation in vitro and the effect of raw diced or juiced carrots on platelet aggregation in a human study. Carrot extract significantly reduced the platelet aggregation in vitro in blood obtained from healthy donors. In a randomised crossover human study, healthy volunteers consumed either 100 g of freshly diced carrots or 100 mL of freshly juiced carrots (with pulp). There was no significant effect on blood platelet aggregation in the participants at 2, 5, 8 and 24 h after the carrot meal due to wide interindividual variations. Further research is required to understand diet, genetics and lifestyle factors that may impact the physiological effects of falcarinol on platelet aggregation and blood flow.     

The role of volatile compounds on aroma and flavour perception in coloured raw carrot genotypes

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.     

Impact of frozen storage on polyacetylene content, texture and colour in carrots disks

This study investigated the effect of freezing method (slow or blast freezing) with or without blanching during storage at −20 °C on the levels of three polyacetylenes, falcarinol (FaOH), falcarindiol (FaDOH), falcarindiol-3-acetate (FaDOAc) in carrot disks. The quality of the carrot disks was also assessed using instrumental texture and colour measurements. Blast frozen carrot disks retained higher amounts of polyacetylenes compared to their slow frozen counterparts. Whilst the levels of retention of total polyacetylenes was higher in unblanched than blanched disks prior to freezing there was a sharp decrease in the levels of polyacetylenes in unblanched frozen carrots during the storage period for 60 days at −20 °C. FaDOH was observed to be the most susceptible to degradation during frozen storage of unblanched carrot disks, followed by FaOH and FaDOAc. The changes in the level of polyacetylenes during storage were adequately described by using Weibull model. The texture and colour were also found to decrease during frozen storage compared to fresh carrots.     

Polyacetylene content and UV-induced 6-methoxymellein accumulation in carrot cultivars

The antifungal polyacetylenes falcarindiol and falcarinol, the production potential of the phytoalexin 6-methoxymellein (6-MM), and the carbohydrate profiles of five carrot cultivars were studied in order to assess variability in their content of these compounds as well as to determine the existence of any interrelationship among them. The polyacetylene content was measured in the peel of carrot roots shortly after harvest; the accumulation of 6-MM was measured in carrot slices incubated at 1°C after exposure to ultraviolet light (UV-C); and the carbohydrate content (glucose, fructose, sucrose and total non-structural), determined on whole carrots. Significant differences among the cultivars were noted in the content of polyacetylenes and 6-MM accumulation as well as in the carbohydrate constituents. The variation among the cultivars for the polyacetylene content and that for the accumulation of 6-MM were found to be independent of each other. The results suggest that cultivars with higher levels of antifungal compounds could be bred in order to improve their resistance to diseases. The carbohydrate profiles of the cultivars did not affect their production of 6-MM. Furthermore, 6-MM accumulation–UV dose response was similar for all the cultivars. Thus, a single dose of UV could be used to induce 6-MM in several cultivars of carrot.     

Training of a sensory panel and profiling of winter hardy and coloured carrot genotypes

The aim of the study was to determine the performance of a sensory panel in evaluation of carrots by investigating the effect of training sessions on the reliability of the sensory attributes. A sensory panel (n = 10) was trained in profiling five carrot genotypes during a training session with seven sensory replications and 13 attributes. A significant effect of training on the sensory profile was determined for bitterness, green flavour and burning aftertaste, indicating that a learning process in judging these attributes was taking place. Terpene flavour, terpene aroma and burning aftertaste were the most reliable determined attributes and carrot flavour, soapiness flavour and nutty flavour were the least reliable attributes. The developed sensory profile was applied on 16 carrot types with a large variation in quality. Winter hardiness, carrot genotype and carrot colour formed distinct groups within the sensory profile, which indicates that the present sensory profile is relevant for assessing sensory quality of carrots. The winter hardy genotypes were characterised by having relatively high intensities in green aroma, carrot aroma, nutty flavour, carrot flavour and sweetness, while the reverse was true for the Nantes types and the coloured carrots with the red and white genotype as being the most extreme.     

Evaluation of the adsorption behavior of polyacetylenes onto a food-grade resin for the debittering of carrot juice

In the present study, a procedure for the adsorptive removal of bitter principles, such as the polyacetylenes falcarinol, falcarindiol, and falcarindiol-3-acetate, from carrot juice using a food-grade macroreticular, non-ionic adsorption resin was investigated. To characterize the adsorption behavior of the target compounds, the influence of the independent factors resin amount, stirring rate, pH value, and temperature was studied first in batch-scale experiments. Based on mathematical models obtained from the analysis of the D-optimal design applied, optimal adsorption conditions of each polyacetylene were deduced. Taking together these findings, the adsorption behavior of polyacetylenes was investigated in column experiments. To enhance the binding rates by increasing contact times, the carrot juice was two- and threefold re-applied to the column at 30 °C. As expected, relative amounts of polyacetylenes bound by the adsorbent increased with prolonged contact time of carrot juice and resin material. After a contact time of 64 min, nearly 90% of total polyacetylenes were sorbed onto the resin surface. Therefore, the described adsorption technique may present a valuable tool for the removal of polyacetylenes from carrot juice and thus for debittering. On the other hand, adsorption may be utilized for the recovery and enrichment of these plant secondary metabolites and their use as a functional ingredient in pharmaceutical products and dietary supplements, respectively.     

Effects of Genotype, Root Size, Storage, and Processing on Bioactive Compounds in Organically Grown Carrots (Daucus carota L.)

ABSTRACT: The effects of genotype, root size, storage, and processing on the content of bioactive compounds in carrots were determined to investigate the possibilities for optimizing the health-promoting properties of this vegetable. The content of polyacetylenes (falcarinol, falcarindiol, falcarindiol-3-acetate), carotenoids (α-and β-carotene), and isocoumarin 6-methoxymellein (6-MM) varied significantly between 6 genotypes of the Nantes type. The content of falcarindiol, falcarindiol-3-acetate, and 6-MM was significantly higher in small (50- to 100-g root size) than in extra large root sizes (>250-g root size). Refrigerated storage of the roots for 4 mo at 1 °C before processing resulted in a significantly higher content of polyacetylenes and no differences in the content of carotenoids and 6-MM compared with frozen storage of processed carrots. The content of falcarinol increased and that of falcarindiol and falcarindiol-3-acetate decreased during steam blanching of the carrots before freezing. No changes were observed in the content of carotenoids and 6-MM.     

Bioactivity of falcarinol and the influenceof processing and storage on its content in carrots (Daucus carota L)

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     

High pressure–temperature degradation kinetics of polyacetylenes in carrots

The present study assessed the effect of high pressure–temperature (HPT) processing on the levels of three polyacetylenes in carrot disks immediately after processing in comparison to sous-vide processing. The degradation kinetics of these compounds following processing at HPT was also investigated. The highest pressure–temperature combination which gave maximum retention during the time 10–30 min, for falcarinol it was 400 MPa, at 50 and 60 °C for 10 min; for falcarindiol it was 400 MPa, at 50 °C for 10 min and for falcarindiol-3-acetate was 400 MPa, at 50 °C for 10 min, respectively. Falcarindiol-3-acetate was found to be most barosensitive and falcarindiol was found to be most thermosensitive of the three polyacetylenes studied. When compared with sous-vide (SV) processed carrot disks, HPT processed samples showed higher retention of polyacetylenes. The changes in the levels of polyacetylenes during HPT treatment were adequately described by Weibull model function.     

Factors contributing to taste and quality of commercially processed strained carrots

Commercially processed strained carrots were obtained from three different processing locations over a 1-year span. Selected carrot lots exhibited both desirable and undesirable sensory attributes based on informal evaluations, while additional carrots were chosen based on postharvest storage factors that may have influenced overall quality. Physicochemical analysis was conducted to determine factors influencing carrot taste and color attributes that could be utilized for retail quality assessment. Quantitative sensory analysis was performed on a subset of the production lots representing a diverse range in chemical composition. Basic taste attributes indicated that concentrations of 6-methoxymellein (6-MM), soluble phenolics and organic acids in relation to high moisture content were critical factors for strained carrot taste. Strained carrot color could not be attributed to processing location or chemical composition and was likely due to raw product variation between cultivars. Variation between each processing location was greater than variation within each location, and overall differences between lots was attributed to 6-MM and soluble phenolic acid concentrations. By screening raw carrots for indications of stress induced chemical constituents, an understanding of those factors contributing to commercially processed strained carrot taste can be obtained.     

Improved loquat (Eriobotrya japonica Lindl.) cultivars: Variation of phenolics and antioxidative potential

Leaves and fruits (peel and flesh) of six improved cultivars (‘Mizuho’, ‘Néctar de Cristal’, ‘Mizauto’, ‘Mizumo’, ‘Centenária’ and ‘NE-3’) of loquat (Eriobotrya japonica Lindl.) were studied for their phenolic composition and antioxidant capacity. The analysis by HPLC-DAD-ESI-MS/MS allowed the identification of 18 compounds (8 hydroxycinnamic acid derivatives and 10 flavonoid glycosides). The quantification of the identified compounds revealed distinct profiles amongst the three analysed materials. Loquat leaves exhibited the lowest amounts of phenolics. 3- And 5-caffeoylquinic, and 5-feruloylquinic acids were the major compounds. Generally, ‘Mizauto’ cultivar presented the highest phenolic content. All loquat materials exhibited DDPH scavenging capacity, in a concentration-dependent manner, the leaves being the most active one. This effect seems to be related to the flavonoid content.     

Polyacetylenes in fresh and stored carrots (Daucus carota): relations to root morphology and sugar content

BACKGROUND: Carrot roots contain polyacetylenes, reported to be both beneficial and distasteful when consumed by humans. This study aimed to investigate the relationships between polyacetylene contents, root morphology and sugar content in order to increase the opportunities to optimise the composition of polyacetylenes in carrots. RESULTS: The falcarinol/total polyacetylene ratio was positively correlated with root size, the amount of sucrose and the sucrose/total soluble sugar ratio among both fresh and stored samples. Root size was inversely correlated with the amounts of falcarindiol and falcarindiol‐3‐acetate, especially among stored samples. Stored carrots exhibited an inverse correlation between polyacetylenes and the amount of soluble sugar. At a falcarinol content at harvest below approximately 200 mg kg^?1 dry weight the amounts of all polyacetylenes increased during storage, but above that level the amounts of all polyacetylenes instead decreased. CONCLUSION: The results indicate similarities in the activity of the enzymes transforming sucrose to hexoses and the enzymes transforming falcarinol to falcarindiol‐3‐acetate and falcarindiol. The negative correlation between root size and polyacetylenes seems to be partly due to dilution but also to a higher synthetisation rate in smaller roots. The results indicate the existence of an equilibrium regulating the level of falcarinol. Copyright © 2011 Society of Chemical Industry     

Evaluation of carrot varieties for production of deep fried carrot chips — II. Sensory aspects

Carrot variety had a significant (P ≤ 0.0005) influence on colour, sweet taste, fruity taste, acid taste, bitter taste, earthy taste, juiciness and crispness, while cultivation site (environmental conditions) had a significant (P ≤ 0.0005) influence on colour, sweet taste, bitter taste, earthy taste, aftertaste, juiciness and crispness. Sensory attributes of raw carrots could predict the quality of carrot chips by means of two factors when PLS has been applied. Factor 1 was explained mainly by cultivation site, but also by variety, while factor 2 was explained by variety.     

Sensory quality of ethylene‐exposed carrots (Daucus carota L,cv ‘Yukon’) related to the contents of 6‐methoxymellein,terpenes and sugars

Carrots were analysed for taste and odour and for contents of terpenes, 6‐methoxymellein and sugars during 3 weeks storage at 15 °C in an atmosphere containing ethylene (1 µl l⁻¹). The ethylene treatment caused an increase in 6‐methoxymellein and the conversion of higher amounts of sucrose to fructose and glucose compared to control carrots stored in air. This corresponded to higher sensory scores for bitterness and terpene flavour and a lower score for sweetness, as measured by an expert taste panel. Principal component analysis showed a more expressed bitter taste, earthy flavour, green flavour, terpene flavour and aftertaste in the ethylene‐treated carrots. Correlations were found between sweet taste and the content of sucrose (r = 0.91, p < 0.005) and between the contents of various terpenes (particularly γ‐terpinene, limonene and caryophyllene) and terpene flavour, green flavour, aftertaste and bitter taste (r ≥ 0.72, p < 0.05). In the air‐stored carrots these off‐flavours seemed to be masked by a high sucrose content. © 2000 Society of Chemical Industry     

Quantification of chicory root bitterness by an ELISA for 11β,13-dihydrolactucin

Chicory root (Cichorium intybus L. var. sativum) is an important foodstuff appreciated for its bitter taste, which is caused by sesquiterpene lactones. These compounds represent a quality parameter for monitoring the raw material. Using polyclonal antibodies, an enzyme-linked immunosorbent assay (ELISA) was developed to quantify the bitter compound 11β,13-dihydrolactucin in chicory root. Assay linearity ranged from 4.6 to 300 ng/ml, with intra- and inter-assay variations of 4.9% and 7.2%, respectively. An IC₅₀ of 2 ng/ml and a detection limit of 0.16 ng/ml were obtained. No or little cross-reactions with other sesquiterpene lactones occurred. Roots of three different chicory varieties were evaluated for their bitter taste and were investigated by the ELISA. Distinct concentrations of 11β,13-dihydrolactucin ranging from 485 to 1720 mg/kg dry matter were correlated with the bitterness degree (r = 0.9). The ELISA appeared sensitive, selective, accurate and may serve as screening tool in breeding of chicory roots for bitterness.     

白酒的"苦味"及其解决措施

白酒中存在许多不同阈值的苦味物质,苦味有时表现为麻苦、焦苦、涩苦、甜苦等,会影响酒体质量,影响消费和企业效益。引起白酒苦味的主要物质有杂醇类、醛类、酚类化合物、硫化物、多肽、氨基酸和无机盐等。其主要来源于原辅料不净、原辅料选择不当或配料不合理以及工艺条件控制不当。解决酒苦味的措施有：控制酒体中的有机酸含量;应用勾兑与调味技术弱化苦味;防止加浆降度用水带入苦味;清蒸辅料、排除其邪杂味;合理配曲使用;加强生产环境卫生;严格控制合理的生产工艺。     

Modelling the effect of water immersion thermal processing on polyacetylene levels and instrumental colour of carrot disks

C₁₇ polyacetylenes are a group of bioactive compounds present in carrots which have recently gained scientific attention due to their cytotoxicity against cancer cells. In common with many bioactive compounds, their levels may be influenced by thermal processes, such as boiling or water immersion. This study investigated the effect of a number of water immersion time/temperature combinations on concentrations of these compounds and attempted to model the changes. Carrot samples were thermally treated by heating in water at temperatures from 50–100 °C and holding times of 2–60 min. Following heating, levels of falcarinol (FaOH), falcarindiol (FaDOH), falcarindiol-3-acetate (FaDOAc) and Hunter colour parameters (L^∗, a^∗, b^∗) were determined. FaOH, FaDOH, FaDOAc levels were significantly reduced at lower temperatures (50–60 °C). In contrast, samples heated at temperatures from 70–100 °C exhibited higher levels of polyacetylenes (p < 0.05) than did raw unprocessed samples. Regression modelling was used to model the effects of temperature and holding time on the levels of the variables measured. Temperature treatment and holding time were found to significantly affect the polyacetylene content of carrot disks. Predicted models were found to be significant (p < 0.05) with high coefficients of determination (R²).     

Sensory quality of turnip greens and turnip tops grown in northwestern Spain

In Galicia (northwestern Spain), Brassica rapa var. rapa L. includes turnip greens and turnip tops as vegetable products that are characterized by a particular sulfurous aroma, pungent flavor, and a bitter taste. In this work, 12 local varieties grown as turnip greens and turnip tops were evaluated to define the sensory attributes, to relate them with secondary metabolites, and to select those sensorial traits that better describe these crops. Results showed differences in the sensory profiles of B. rapa varieties. Turnip greens were significantly different regarding aroma intensity, leaf color, and salty taste, while turnip tops were for color and firmness of leaves, moistness and fibrosity in mouth, sharpness, and bitter taste. Secondary metabolites as glucosinolates in turnip greens and phenolic compounds in turnip tops were highly correlated with texture and flavor. Glucosinolates, especially progoitrin (in turnip greens) and gluconapin (in turnip tops), showed correlation with bitter taste and aftertaste persistence. Correlation between sensory traits showed highest values between leaf firmness and stalk firmness (R = 0.94**), leaf firmness and fibrosity (R = 0.92**), aftertaste persistence and bitterness (R = 0.91**), and between bitterness and moistness (R = −0.89**).