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Koen Dewettinck - One of the best experts on this subject based on the ideXlab platform.
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Impact of Thermal Treatment on Physicochemical, Antioxidative and Rheological Properties of White-Flesh and Red-Flesh Dragon Fruit (Hylocereus spp.) Purees
Food and Bioprocess Technology, 2013Co-Authors: Wijitra Liaotrakoon, Nathalie Clercq, Vera Hoed, Davy Walle, Benny Lewille, Koen DewettinckAbstract:White-flesh ( Hylocereus undatus ; WF) and red-flesh ( Hylocereus polyrhizus ; RF) dragon fruit purees were subjected to heat treatment for 0 to 60 min at temperatures between 50 and 90 °C. The influence of the different heat treatments on the physicochemical properties, colour, betacyanins content, microbial destruction, antioxidative properties and rheological parameters were investigated. The physicochemical values and antioxidative properties of the unheated RF were significantly higher than that of the unheated WF ( p
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Impact of Thermal Treatment on Physicochemical, Antioxidative and Rheological Properties of White-Flesh and Red-Flesh Dragon Fruit (Hylocereus spp.) Purees
Food and Bioprocess Technology, 2011Co-Authors: Wijitra Liaotrakoon, Nathalie Clercq, Vera Hoed, Davy Walle, Benny Lewille, Koen DewettinckAbstract:White-flesh (Hylocereus undatus; WF) and red-flesh (Hylocereus polyrhizus; RF) dragon fruit purees were subjected to a heat treatment for 0 to 60 min at temperatures between 50 and 90 °C. The influence of the different heat treatments on the physicochemical properties, colour, betacyanins content, microbial destruction, antioxidative properties and rheological parameters were investigated. The physicochemical values and antioxidative properties of the unheated RF were significantly higher than that of the unheated WF (p 0.7733) and TCC of RF can be used to predict the betacyanins content (R2 = 0.9442). The antioxidative properties of the heated WF and RF increased with heating treatment. The linear correlation among the antioxidative properties was strong (R2 > 0.8587). WF and RF showed shear thinning behaviour. After heating, the apparent viscosity of WF and RF increased and all cases fitted very well with the power law model (R2 > 0.9988). Thus, the heated dragon fruit purees, particularly the RF, offer possibilities to be applied in foodstuffs due to their interesting physicochemical properties and nutritional attributes after thermal treatment.
Reinhold Carle - One of the best experts on this subject based on the ideXlab platform.
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Pigment pattern and expression of colour in fruits from different Hylocereus sp. genotypes
Innovative Food Science & Emerging Technologies, 2007Co-Authors: Patricia Esquivel, Florian C Stintzing, Reinhold CarleAbstract:Abstract Pigment profiles, betalain contents, colour and pH-values were studied in fruits from five Hylocereus sp. genotypes originating from Costa Rica. Significant colour differences between fruit pulps from “Nacional” and “San Ignacio” were found for C⁎-values and “Lisa” exhibited the most reddish tint h°. Whereas highest betalain contents were registered in “San Ignacio” and “Orejona”, lowest values were found in “Nacional”. Additionally, pigment patterns of the genotypes were found to differ: While “Lisa”, “Nacional” and “Orejona” were characterised by a similar betalain pattern, “Rosa” and “San Ignacio” were significantly different offering a valuable tool for genotype comparison. Moreover, “Rosa” showed the highest betanin and isobetanin contents, whereas phyllocactin and hylocerenin were predominant in “San Ignacio”. Apart from the newly reported betalains neobetanin and gomphrenin I, indicaxanthin was the first betaxanthin so far detected in pitaya fruits. Industrial relevance Natural substitutes for synthetic colourants are increasingly gaining importance on the global market. In particular, the so-called colouring foodstuffs representing aqueous or oily plant extracts extend their market share with red-coloured preparations being particularly requested. In this regard, pitaya fruits from the genotype Hylocereus have been proposed as promising colour sources, recently. To secure the authenticity of the plant material, a reliable differentiation of pitayas from different origins is required. In addition, Hylocereus fruits may differ in their colour quality and pigment content, the knowledge of which is crucial for the selection of appropriate plants for an emerging pitaya market.
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colour studies on fruit juice blends from opuntia and Hylocereus cacti and betalain containing model solutions derived therefrom
Food Research International, 2005Co-Authors: Markus R Moshammer, Florian C Stintzing, Reinhold CarleAbstract:Abstract The visual appearance and pigment stability of fruit juice blends from Opuntia and Hylocereus cacti and of betalain-containing model solutions derived therefrom were investigated at pH values ranging from 3 to 7. All samples were found to be stable as indicated by betalain contents as well as hue and chroma values over the complete pH range monitored. Both the juice and the purified betaxanthin solution from Opuntia ficus-indica cv. ‘Gialla’ were characterised by yellowish hues, while the juice and the purified betacyanin solution from Hylocereus polyrhizus displayed purplish tonalities. By blending the betaxanthin and betacyanin stock solutions, tailor-made hues covering the entire spectrum from bright yellow (h° = 84) to purplish-blue (h° = 333) were successfully produced. Since mixtures from purified betalains did not provide colour shades different from those obtained with raw cactus fruit juices, the use of the latter should be preferred both because of consumer-friendly labelling and improved pigment stability.
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Evaluation of colour properties and chemical quality parameters of cactus juices
European Food Research and Technology, 2003Co-Authors: Florian C Stintzing, Andreas Schieber, Reinhold CarleAbstract:The chemical composition and visual appearance of cactus fruits from the genera Opuntia and Hylocereus were investigated. Colour properties were assessed in solutions with pH ranging from 1 to 8 and expressed as chroma, hue and colour shade. Between pH 3 and 7, all samples were stable as indicated by hue and chroma values. The colour shade of the red juice of Opuntia ficus-indica cv. 'Rossa' was in the range of red beet preparations hitherto most commonly used for colouring low-acid food commodities. Hylocereus was characterized by purplish hues, whereas the juice from O. ficus-indica cv. 'Gialla' displayed a yellow tonality. An improved spectrophotometric method for pigment quantification was proposed. Betacyanin contents were 525.3, 73.9 and 1.3 mg/l in juices from Hylocereus polyrhizus, Opuntia ficus-indica cv. 'Rossa' and O. ficus-indica cv. 'Gialla', whereas betaxanthins amounted to 48.3, 36.4 and 5.3 mg/l in O. ficus-indica cv. 'Gialla', O. ficus-indica cv. 'Rossa', and H. polyrhizus, respectively. Although the colourless fruits from O. ficus-indica cv. 'Bianca' and H. undatus could not be considered as a colour source, selected quality parameters were also investigated with respect to their nutritional value. To the best of our knowledge, this is the first report about the chemical quality parameters of H. polyrhizus and H. undatus.
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betacyanins in fruits from red purple pitaya Hylocereus polyrhizus weber britton rose
Food Chemistry, 2002Co-Authors: Florian C Stintzing, Andreas Schieber, Reinhold CarleAbstract:Abstract The betalain pattern of Hylocereus polyrhizus (Weber) Britton & Rose is reported for the first time and a highly practicable technique is described for the simultaneous isolation of pigment and mucilage from the mesocarp by extraction with water. Whereas betaxanthins were totally absent, 10 betacyanins could be separated by HPLC-PDA. For eight betacyanins the respective molecular masses could be obtained by positive ion electrospray mass spectrometry. Five of them were unequivocally assigned to bougainvillein-r-I, betanin, isobetanin, phyllocactin, and iso-phyllocactin. The remaining betacyanins were tentatively identified as (6′-O-3-hydroxy-3-methyl-glutaryl)-betanin, its C15-stereoisomer, and (6′-O-3-hydroxy-3–butyryl)-betanin, respectively. Using the β-glucosidase assay, acylated structures could be distinguished from non-acylated betacyanins. Contrary to white-fleshed Hylocereus undatus (Haworth) Britton & Rose with a slightly pink mesocarp, H. polyrhizus most likely possesses the same set of betalain forming enzymes in both pulp and mesocarp as the betacyanin pattern was found to be similar.
Lee Fong Siow - One of the best experts on this subject based on the ideXlab platform.
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effects of heat ph antioxidant agitation and light on betacyanin stability using red fleshed dragon fruit Hylocereus polyrhizus juice and concentrate as models
Journal of Food Science and Technology-mysore, 2015Co-Authors: Yen Ming Wong, Lee Fong SiowAbstract:Red-fleshed dragon fruit (Hylocereus polyrhizus) is rich in antioxidants. The aim of this study was to determine the effects of heat pasteurization, pH adjustment, ascorbic acid addition as well as storage under agitation and light or dark condition on betacyanin content in red-fleshed dragon fruit (Hylocereus polyrhizus) juice and concentrate. The concentrate was produced by concentrating clarified red-fleshed dragon fruit juice in a rotary evaporator at 40 °C. UV-Visible spectrophotometer was used for analyzing betacyanin content. Addition of 0.25 % ascorbic acid, pH 4.0, and pasteurization at 65 °C for 30 min were selected as the best processing conditions to retain betacyanin content in red-fleshed dragon fruit juice. Storage at the agitation speed of 220 rpm showed that the concentrated samples had higher betacyanin stability compared to juice, while both juice and concentrate had almost similar betacyanin stability when tested for storage in the presence of light. In summary, ascorbic acid stabilized betacyanin in both juice and concentrate at agitated or non-agitated conditions. In contrast, light degraded betacyanin in both juice and concentrate models.
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Spray drying of red (Hylocereus polyrhizus) and white (Hylocereus undatus) dragon fruit juices: physicochemical and antioxidant properties of the powder
International Journal of Food Science and Technology, 2013Co-Authors: Kar-hing Lee, Lee Fong SiowAbstract:Summary This study aims to investigate physical stability and antioxidant properties of spray-dried red (Hylocereus polyrhizus) and white (Hylocereus undatus) dragon fruit powder upon storage at various relative humidity (RH). Inlet air temperatures of 120 °C (red dragon fruit) and 110 °C (white dragon fruit) as well as maltodextrin concentration of 30% (w/v) were selected as the spray drying conditions as powder was obtained at these minimum conditions. The powder was ranging from 3 to 7 μm in particle size with spherical morphology. The powder had lower antioxidant content and antioxidant activities compared with the control before spray drying. Storage of powder at 43%, 54% or 75% RH at 25 °C for 25 days resulted in structural changes correlating to the depression of glass transition temperatures (Tg) to below storage temperature. At 33% RH, no visible structural changes were observed. Antioxidant properties of the powder remained unchanged after 25 days' storage at the studied RHs.
Yosef Mizrahi - One of the best experts on this subject based on the ideXlab platform.
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Genetic Relationships among Hylocereus and Selenicereus Vine Cacti (Cactaceae): Evidence from Hybridization and Cytological Studies
Annals of botany, 2004Co-Authors: Noemi Tel-zur, Shahal Abbo, Dudy Bar-zvi, Yosef MizrahiAbstract:� Background and Aims Hylocereus and Selenicereus are native to tropical and sub-tropical America. Based on its taxonomic status and crossability relations it was postulated that H. megalanthus (syn. S. megalanthus )i s an allotetraploid (2n = 4x = 44) derived from natural hybridization between two closely related diploid taxa. The present work aimed at elucidating the genetic relationships between species of the two genera. � Methods Crosses were performed and the putative hybrids were analysed by chromosome counts and morphological traits. The ploidy level of hybrids was confirmed by fluorescent in situ hybridization (FISH) of rDNA sites. Genomic in situ hybridization (GISH) was used in an attempt to identify the putative diploid genome donors of H. megalanthus and an artificial interploid hybrid. � Key Results Reciprocal crosses among four diploid Hylocereus species (H. costaricensis, H. monacanthus (syn. H. polyrhizus), H. undatus and Hylocereus sp.) yielded viable diploid hybrids, with regular chromosome pairing. Reciprocal crosses between these Hylocereus spp. and H. megalanthus yielded viable triploid, pentaploid, hexaploid and aneuploid hybrids. Morphological and phenological traits confirm the hybrid origin. In situ detection of rDNA sites was in accord with the ploidy status of the species and hybrid studied. GISH results indicated that overall sequence composition of H. megalanthus is similar to that of H. ocamponis and S. grandiflorus. High sequence similarity was also found between the parental genomes of H. monacanthus and H. megalanthus in one triploid hybrid. � Conclusions The ease of obtaining partially fertile F1 hybrids and the relative sequence similarity (in GISH study) suggest close genetic relationships among the taxa analysed. a 2004 Annals of Botany Company
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Metaxenia in the Vine Cacti Hylocereus polyrhizus and Selenicereus spp.
Annals of botany, 2004Co-Authors: Yosef Mizrahi, Avinoam Nerd, Joseph Mouyal, Yaron SitritAbstract:• Background and Aims Flowers of the vine cacti of the genera Hylocereus and Selenicereus grown in Israel must be hand pollinated due to self‐incompatibility and lack of efficient pollinators. In controlled pollination experiments, it was found that the time elapsed between pollination and ripening depends on the source of the pollen. Therefore a study was made of some effects of the pollen source on fruit development. • Methods Flowers of Hylocereus polyrhizus were pollinated on the same day with different pollen sources and the stigmas were covered. Fruits were collected 4 d after reaching full colour. • Key Results Pollinating flowers of Hylocereus polyrhizus with Selenicereus grandiflorus and S. megalanthus pollen delayed ripening by 1 and 3 weeks, respectively, as compared with ripening of fruits pollinated with Hylocereus undatus pollen. Other fruit characteristics affected by the pollen source were fruit size, pulp dry weight and number of seeds per fruit, all being significantly reduced, while peel dry weight was significantly increased by S. megalanthus pollen. Total soluble sugar content was reduced in H. polyrhizus fruits pollinated with S. grandiflorus pollen. No other major traits were affected. • Conclusions The results are evidence for the existence of metaxenia, i.e. an effect of pollen on maternal tissues, in cacti fruits. This pollen effect on the fruit‐ripening time may be used for extending the marketing period of H. polyrhizus fruits.
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Clone identification and genetic relationship among vine cacti from the genera Hylocereus and Selenicereus based on RAPD analysis
Scientia Horticulturae, 2003Co-Authors: Noemi Tel-zur, Shahal Abbo, Dudy Bar-zvi, Yosef MizrahiAbstract:Clones of Hylocereus and of Selenicereus species were distinguished from each other by the banding pattern generated by one to nine 10-mer oligonucleotide primers in the random amplified polymorphic DNA (RAPD) reaction. RAPD analysis was also applied to estimate the genetic relationship among five Hylocereus and nine Selenicereus species. A dendrogram was constructed based on a data matrix of 173 polymorphic bands originated by nine primers. Two groups were identified, one consisting of Hylocereus species and the other consisting of Selenicereus species. These results are consistent with the accepted taxonomic classification of the genera studied. The principal coordinate analysis (PCO), i.e. the plot drawn on the basis of the RAPD data, clearly distinguished between three groups, namely, Hylocereus species, S. megalanthus and the rest of the Selenicereus species studied. PCO thus strongly support the notion that the tetraploid S. megalanthus is an exception among the Selenicereus group. The RAPD results support our hypothesis regarding the allopolyploid (rather than autopolyploid) origin of this species.
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Cytology and mating systems in the climbing cacti Hylocereus and Selenicereus
American journal of botany, 2000Co-Authors: Judith Lichtenzveig, Shahal Abbo, Avinoam Nerd, Noemi Tel-zur, Yosef MizrahiAbstract:Chromosome numbers and meiotic behavior are reported for the climbing cacti species Hylocereus undatus, Hylocereus polyrhizus, and Selenicereus megalanthus.The Hylocereus spp. are diploid (2n 5 22), while S. megalanthus is a tetraploid (2n 5 44). Irregular chromosome disjunction at anaphase I in pollen mother cells of S. megalanthus is probably the major cause of its reduced pollen viability and may contribute to low seed set, low number of viable seeds and, consequently, low fruit mass. A pollination study confirmed self-incompatibility in H. polyrhizus and a weakened incompatibility reaction in H. undatus and S. megalanthus. Major crossability barriers do not exist between the Hylocereus spp. investigated. Reciprocal intergeneric crosses were successful between Hylocereus spp. and S. megalanthus, suggesting that an Hylocereus sp. might be one of the diploid progenitors of the tetraploid S. megalanthus. The implications of the results on cacti nomenclature and systematics are briefly discussed.
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Viability of Pollen of Two Fruit Crop Cacti of the Genus Hylocereus Is Affected by Temperature and Duration of Storage
Hortscience, 2000Co-Authors: Christiane Metz, Avinoam Nerd, Yosef MizrahiAbstract:Additional index words. Hylocereus undatus, Hylocereus polyrhizus , dehydration, pollen quality Abstract. Hylocereus undatus (Haw.) and H. polyrhizus (Weber) are new fruit crops of the Cactaceae. In Israel, flowers of the two species, which are self-incompatible, are hand cross-pollinated. In order to ensure a current supply of compatible pollen and guarantee good yields, we have developed a procedure for long-term storage of pollen. Pollen for storage was collected in the evening or in the morning. Its moisture content ranged between 45% to 50% in the evening and between 18% to 22% in the morning. Pollen was first dehydrated in a vacuum desiccator until the moisture content was reduced to 5% to 10% and then stored at various temperatures (+4, -18, -70, -196 °C) for 3 or 9 months, after which it was used for cross-pollination. Percent fruit set and fruit fresh weight (FW) were affected by the temperature but not the duration of pollen storage; storage at +4 °C reduced fruit set, fruit FW, and seed number more than did storage at subfreezing temperatures. The FW of fruits produced by frozen pollen was similar to that produced by fresh pollen in commercial orchards. The rate of seed germination was high ( ≈90%) regardless of the temperature during pollen storage.
Wijitra Liaotrakoon - One of the best experts on this subject based on the ideXlab platform.
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Impact of Thermal Treatment on Physicochemical, Antioxidative and Rheological Properties of White-Flesh and Red-Flesh Dragon Fruit (Hylocereus spp.) Purees
Food and Bioprocess Technology, 2013Co-Authors: Wijitra Liaotrakoon, Nathalie Clercq, Vera Hoed, Davy Walle, Benny Lewille, Koen DewettinckAbstract:White-flesh ( Hylocereus undatus ; WF) and red-flesh ( Hylocereus polyrhizus ; RF) dragon fruit purees were subjected to heat treatment for 0 to 60 min at temperatures between 50 and 90 °C. The influence of the different heat treatments on the physicochemical properties, colour, betacyanins content, microbial destruction, antioxidative properties and rheological parameters were investigated. The physicochemical values and antioxidative properties of the unheated RF were significantly higher than that of the unheated WF ( p
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Impact of Thermal Treatment on Physicochemical, Antioxidative and Rheological Properties of White-Flesh and Red-Flesh Dragon Fruit (Hylocereus spp.) Purees
Food and Bioprocess Technology, 2011Co-Authors: Wijitra Liaotrakoon, Nathalie Clercq, Vera Hoed, Davy Walle, Benny Lewille, Koen DewettinckAbstract:White-flesh (Hylocereus undatus; WF) and red-flesh (Hylocereus polyrhizus; RF) dragon fruit purees were subjected to a heat treatment for 0 to 60 min at temperatures between 50 and 90 °C. The influence of the different heat treatments on the physicochemical properties, colour, betacyanins content, microbial destruction, antioxidative properties and rheological parameters were investigated. The physicochemical values and antioxidative properties of the unheated RF were significantly higher than that of the unheated WF (p 0.7733) and TCC of RF can be used to predict the betacyanins content (R2 = 0.9442). The antioxidative properties of the heated WF and RF increased with heating treatment. The linear correlation among the antioxidative properties was strong (R2 > 0.8587). WF and RF showed shear thinning behaviour. After heating, the apparent viscosity of WF and RF increased and all cases fitted very well with the power law model (R2 > 0.9988). Thus, the heated dragon fruit purees, particularly the RF, offer possibilities to be applied in foodstuffs due to their interesting physicochemical properties and nutritional attributes after thermal treatment.