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Leandro Peña - One of the best experts on this subject based on the ideXlab platform.

  • Engineering d‐limonene synthase down‐regulation in Orange Fruit induces resistance against the fungus Phyllosticta citricarpa through enhanced accumulation of monoterpene alcohols and activation of defence
    Molecular plant pathology, 2018
    Co-Authors: Ana Rodríguez, Vanessa Kava, Lorena Latorre-garcía, G. J. Silva, Rosana G. Pereira, Chirlei Glienke, Lisandra Santos Ferreira-maba, Antonio Vicent, Takehiko Shimada, Leandro Peña
    Abstract:

    Terpene volatiles play an important role in the interactions between specialized pathogens and Fruits. Citrus black spot (CBS), caused by the fungus Phyllosticta citricarpa, is associated with crop losses in different citrus-growing areas worldwide. The pathogen may infect the Fruit for 20-24 weeks after petal fall, but the typical hard spot symptoms appear when the Fruit have almost reached maturity, caused by fungal colonization and the induction of cell lysis around essential oil cavities. d-Limonene represents approximately 95% of the total oil gland content in mature Orange Fruit. Herein, we investigated whether Orange Fruit with reduced d-limonene content in peel oil glands via an antisense (AS) approach may affect Fruit interaction with P. citricarpa relative to empty vector (EV) controls. AS Fruit showed enhanced resistance to the fungus relative to EV Fruit. Because of the reduced d-limonene content, an over-accumulation of linalool and other monoterpene alcohols was found in AS relative to EV Fruit. A global gene expression analysis at 2 h and 8 days after inoculation with P. citricarpa revealed the activation of defence responses in AS Fruit via the up-regulation of different pathogenesis-related (PR) protein genes, probably as a result of enhanced constitutive accumulation of linalool and other alcohols. When assayed in vitro and in vivo, monoterpene alcohols at the concentrations present in AS Fruit showed strong antifungal activity. We show here that terpene engineering in Fruit peels could be a promising method for the development of new strategies to obtain resistance to Fruit diseases.

  • metabolic engineering of β carotene in Orange Fruit increases its in vivo antioxidant properties
    Plant Biotechnology Journal, 2014
    Co-Authors: Elsa Pons, Berta Alquézar, Ana Rodríguez, Patricia Martorell, Salvador Genovés, Daniel Ramón, María Jesús Rodrigo, Lorenzo Zacarías, Leandro Peña
    Abstract:

    Orange is a major crop and an important source of health-promoting bioactive compounds. Increasing the levels of specific antioxidants in Orange Fruit through metabolic engineering could strengthen the Fruit's health benefits. In this work, we have afforded enhancing the β-carotene content of Orange Fruit through blocking by RNA interference the expression of an endogenous β-carotene hydroxylase gene (Csβ-CHX) that is involved in the conversion of β-carotene into xanthophylls. Additionally, we have simultaneously overexpressed a key regulator gene of flowering transition, the FLOWERING LOCUS T from sweet Orange (CsFT), in the transgenic juvenile plants, which allowed us to obtain Fruit in an extremely short period of time. Silencing the Csβ-CHX gene resulted in Oranges with a deep yellow ('golden') phenotype and significant increases (up to 36-fold) in β-carotene content in the pulp. The capacity of β-carotene-enriched Oranges for protection against oxidative stress in vivo was assessed using Caenorhabditis elegans as experimental animal model. Golden Oranges induced a 20% higher antioxidant effect than the isogenic control. This is the first example of the successful metabolic engineering of the β-carotene content (or the content of any other phytonutrient) in Oranges and demonstrates the potential of genetic engineering for the nutritional enhancement of Fruit tree crops.

  • Metabolic engineering of β‐carotene in Orange Fruit increases its in vivo antioxidant properties
    Plant biotechnology journal, 2013
    Co-Authors: Elsa Pons, Berta Alquézar, Ana Rodríguez, Patricia Martorell, Salvador Genovés, Daniel Ramón, María Jesús Rodrigo, Lorenzo Zacarías, Leandro Peña
    Abstract:

    Summary Orange is a major crop and an important source of health-promoting bioactive compounds. Increasing the levels of specific antioxidants in Orange Fruit through metabolic engineering could strengthen the Fruit’s health benefits. In this work, we have afforded enhancing the b-carotene content of Orange Fruit through blocking by RNA interference the expression of an endogenous b-carotene hydroxylase gene (Csb-CHX) that is involved in the conversion of b-carotene into xanthophylls. Additionally, we have simultaneously overexpressed a key regulator gene of flowering transition, the FLOWERING LOCUS T from sweet Orange (CsFT), in the transgenic juvenile plants, which allowed us to obtain Fruit in an extremely short period of time. Silencing the Csb-CHX gene resulted in Oranges with a deep yellow (‘golden’) phenotype and significant increases (up to 36-fold) in b-carotene content in the pulp. The capacity of b-carotene-enriched Oranges for protection against oxidative stress in vivo was assessed using Caenorhabditis elegans as experimental animal model. Golden Oranges induced a 20% higher antioxidant effect than the isogenic control. This is the first example of the successful metabolic engineering of the b-carotene content (or the content of any other phytonutrient) in Oranges and demonstrates the potential of genetic engineering for the nutritional enhancement of Fruit tree crops.

María Jesús Rodrigo - One of the best experts on this subject based on the ideXlab platform.

  • metabolic engineering of β carotene in Orange Fruit increases its in vivo antioxidant properties
    Plant Biotechnology Journal, 2014
    Co-Authors: Elsa Pons, Berta Alquézar, Ana Rodríguez, Patricia Martorell, Salvador Genovés, Daniel Ramón, María Jesús Rodrigo, Lorenzo Zacarías, Leandro Peña
    Abstract:

    Orange is a major crop and an important source of health-promoting bioactive compounds. Increasing the levels of specific antioxidants in Orange Fruit through metabolic engineering could strengthen the Fruit's health benefits. In this work, we have afforded enhancing the β-carotene content of Orange Fruit through blocking by RNA interference the expression of an endogenous β-carotene hydroxylase gene (Csβ-CHX) that is involved in the conversion of β-carotene into xanthophylls. Additionally, we have simultaneously overexpressed a key regulator gene of flowering transition, the FLOWERING LOCUS T from sweet Orange (CsFT), in the transgenic juvenile plants, which allowed us to obtain Fruit in an extremely short period of time. Silencing the Csβ-CHX gene resulted in Oranges with a deep yellow ('golden') phenotype and significant increases (up to 36-fold) in β-carotene content in the pulp. The capacity of β-carotene-enriched Oranges for protection against oxidative stress in vivo was assessed using Caenorhabditis elegans as experimental animal model. Golden Oranges induced a 20% higher antioxidant effect than the isogenic control. This is the first example of the successful metabolic engineering of the β-carotene content (or the content of any other phytonutrient) in Oranges and demonstrates the potential of genetic engineering for the nutritional enhancement of Fruit tree crops.

  • Metabolic engineering of β‐carotene in Orange Fruit increases its in vivo antioxidant properties
    Plant biotechnology journal, 2013
    Co-Authors: Elsa Pons, Berta Alquézar, Ana Rodríguez, Patricia Martorell, Salvador Genovés, Daniel Ramón, María Jesús Rodrigo, Lorenzo Zacarías, Leandro Peña
    Abstract:

    Summary Orange is a major crop and an important source of health-promoting bioactive compounds. Increasing the levels of specific antioxidants in Orange Fruit through metabolic engineering could strengthen the Fruit’s health benefits. In this work, we have afforded enhancing the b-carotene content of Orange Fruit through blocking by RNA interference the expression of an endogenous b-carotene hydroxylase gene (Csb-CHX) that is involved in the conversion of b-carotene into xanthophylls. Additionally, we have simultaneously overexpressed a key regulator gene of flowering transition, the FLOWERING LOCUS T from sweet Orange (CsFT), in the transgenic juvenile plants, which allowed us to obtain Fruit in an extremely short period of time. Silencing the Csb-CHX gene resulted in Oranges with a deep yellow (‘golden’) phenotype and significant increases (up to 36-fold) in b-carotene content in the pulp. The capacity of b-carotene-enriched Oranges for protection against oxidative stress in vivo was assessed using Caenorhabditis elegans as experimental animal model. Golden Oranges induced a 20% higher antioxidant effect than the isogenic control. This is the first example of the successful metabolic engineering of the b-carotene content (or the content of any other phytonutrient) in Oranges and demonstrates the potential of genetic engineering for the nutritional enhancement of Fruit tree crops.

  • stimulation of coloration and carotenoid biosynthesis during postharvest storage of navelina Orange Fruit at 12 c
    Postharvest Biology and Technology, 2012
    Co-Authors: Lourdes Carmona, Lorenzo Zacarías, María Jesús Rodrigo
    Abstract:

    Abstract The effect of storage temperature on color, carotenoid content and composition, and the expression of key carotenoid biosynthetic genes in Fruit of ‘Navelina’ Orange were evaluated. Fruit were harvested at two maturation stages, before color break (breaker stage) and with a light-Orange coloration (colored), and stored at 2 and 12 °C and 90–95% RH for up to 7 weeks. At the two maturation stages, storage at 12 °C considerably increased total carotenoid content and enhanced coloration in both flavedo and pulp. In Fruit stored at 2 °C, coloration and carotenoid content remained almost unchanged. The increase in peel color during storage at 12 °C was mainly related to an increment in the concentration of the reddish C30-apocarotenoid, β-citraurin, and to a minor extent to antheraxanthin. The content of β-cryptoxanthin, a β,β-xanthophyll with pro-vitamin A activity, increased two and three times in the pulp of breaker and colored Fruit, respectively, after 7 weeks of storage at 12 °C. The expression of the genes PSY (phytoene synthase), PDS (phytoene desaturase), ZDS (ζ-carotene desaturase), βLCY1 and βLCY2 (β-lycopene cyclase 1 and 2) and βCHX (β-carotene hydroxylase) increased during storage at 12 °C in the peel of Fruit at both maturation stages. At 2 °C, by contrast, expression of these genes was maintained or slightly declined. The pattern of changes in gene expression in the pulp of Orange Fruit stored at 12 °C was dependent of the ripening stage and not always related to the increment in carotenoid content and composition. Collectively, these results indicate that the stimulation of carotenoid biosynthesis during storage of ‘Navelina’ Orange Fruit at 12 °C improve not only peel and pulp coloration, but also pro-vitamin A activity of the flesh, and may then be a postharvest strategy to increase the nutritional and health-related benefits of citrus Fruit.

  • Stimulation of coloration and carotenoid biosynthesis during postharvest storage of 'Navelina' Orange Fruit at 12 ◦ C
    Postharvest Biology and Technology, 2012
    Co-Authors: Lourdes Carmona, Lorenzo Zacarías, María Jesús Rodrigo
    Abstract:

    Abstract The effect of storage temperature on color, carotenoid content and composition, and the expression of key carotenoid biosynthetic genes in Fruit of ‘Navelina’ Orange were evaluated. Fruit were harvested at two maturation stages, before color break (breaker stage) and with a light-Orange coloration (colored), and stored at 2 and 12 °C and 90–95% RH for up to 7 weeks. At the two maturation stages, storage at 12 °C considerably increased total carotenoid content and enhanced coloration in both flavedo and pulp. In Fruit stored at 2 °C, coloration and carotenoid content remained almost unchanged. The increase in peel color during storage at 12 °C was mainly related to an increment in the concentration of the reddish C30-apocarotenoid, β-citraurin, and to a minor extent to antheraxanthin. The content of β-cryptoxanthin, a β,β-xanthophyll with pro-vitamin A activity, increased two and three times in the pulp of breaker and colored Fruit, respectively, after 7 weeks of storage at 12 °C. The expression of the genes PSY (phytoene synthase), PDS (phytoene desaturase), ZDS (ζ-carotene desaturase), βLCY1 and βLCY2 (β-lycopene cyclase 1 and 2) and βCHX (β-carotene hydroxylase) increased during storage at 12 °C in the peel of Fruit at both maturation stages. At 2 °C, by contrast, expression of these genes was maintained or slightly declined. The pattern of changes in gene expression in the pulp of Orange Fruit stored at 12 °C was dependent of the ripening stage and not always related to the increment in carotenoid content and composition. Collectively, these results indicate that the stimulation of carotenoid biosynthesis during storage of ‘Navelina’ Orange Fruit at 12 °C improve not only peel and pulp coloration, but also pro-vitamin A activity of the flesh, and may then be a postharvest strategy to increase the nutritional and health-related benefits of citrus Fruit.

Mauro Moresi - One of the best experts on this subject based on the ideXlab platform.

  • Assessment of quality-assured Tarocco Orange Fruit sorting rules by combined physicochemical and sensory testing
    Journal of the Science of Food and Agriculture, 2013
    Co-Authors: Federico Pallottino, Maria Carmela Lanza, Maria Concetta Strano, Francesca Antonucci, Paolo Menesatti, Mauro Moresi
    Abstract:

    BACKGROUND: The aim of this study was to extract a sorting rule for Tarocco Orange Fruit from several physicochemical and sensory tests performed on a marketable lot of 399 Tarocco Orange Fruits. RESULTS: The elastic tension at 5% strain (T5) was found to be linearly correlated (r = 0.65) with the MagnessTaylor (MT) index. Thus T5 was regarded as a non-destructive parameter quantifying Fruit firmness and used to categorise the aforementioned lot in three different firmness classes, high (HF), medium (MF) and low (LF). Only the MT index, Fruit rind thickness near the Fruit peduncle, lightness coefficient and yellow/blue hue component of the Orange flesh, as well as total soluble solid content, confirmed the validity of this discrimination at the significance level of 5%. Sensory professionals recognised the greater compactness (7 +/- 2) but lower ease of peeling (4 +/- 2) and segment separation (4 +/- 2) of the HF Oranges with respect to the corresponding sensory attributes of Orange Fruits grouped in the MF and LF classes. CONCLUSION: To limit the costly rejection of Tarocco Orange Fruit considered too soft, especially after long-term shipping, it would be reasonable to select only Fruits characterised by a compressive force or tension at 5% strain in the range 2341 N or 300540 N m1 respectively. (c) 2012 Society of Chemical Industry

  • Viscoelastic Properties of Tarocco Orange Fruit
    Food and Bioprocess Technology, 2011
    Co-Authors: Mauro Moresi, Federico Pallottino, Corrado Costa, Paolo Menesatti
    Abstract:

    In this work, the rheometrical behaviour of Tarocco Orange Fruit was assessed via stress–relaxation testing under constant engineering strain (ez) in the range of 5–20% of the initial Fruit height, each test being prolonged for 15 min and replicated 20 times. The time course of the experimental dimensionless relaxation modulus (G*) was typical of a viscoelastic solid and was reconstructed by considering two Maxwell elements in parallel to an elastic spring element. In a more restricted ez range (i.e. 5–10%), the dimensionless viscoelastic constants (Ai) were found to be approximately constant, the elastic component responsible for the equilibrium residual stress representing about 42% of the initial relaxation modulus. After any Orange Fruit had been submitted to stress–relaxation testing and decompressed for 5 min, it exhibited a practically negligible mass loss (0.04 ± 0.03%) and a permanent volume contraction rising from 1.7 ± 1.0% to 3.0 ± 0.9% as ez was increased from 5% to 10%. Thus, by tasting the Orange Fruit firmness at ez ≤5%, Fruit response, being of the viscoelastic type, is expected to give rise to nearly irrelevant deformations.

  • Assessment of the mechanical properties of Tarocco Orange Fruit under parallel plate compression
    Journal of Food Engineering, 2011
    Co-Authors: Federico Pallottino, Paolo Menesatti, Corrado Costa, Mauro Moresi
    Abstract:

    Abstract In this work the mechanical compressive properties of Orange Fruits of the Tarocco variety were assessed using a Universal Testing Machine, equipped with upper and lower plates made of transparent graduated Plexiglas® and three cameras positioned along the axis lines x, y and z. By submitting each Fruit to different engineering strains (ez) along the z-axis in the range of 3–21% of the initial Fruit height, the momentary contact area of each Fruit under testing was precisely determined by approximating its outline to a polygon and reconstructing it via the Elliptic Fourier Analysis, or an ellipse inscribed in a bounding box. Both estimates yielded no statistically significant difference and varied linearly with ez. Their prediction using the ASABE Standard Method (2008) , or assuming no variation in the volume of the Fruit undergoing compression, resulted be under- or over-estimated by 45% or 19%, respectively. Use of image analysis allowed the apparent Poisson’s ratio and modulus of deformability (EO) of the whole Orange Fruit to be estimated as equal to 0.16 ± 0.09 and 353 ± 3 kPa, respectively. By assimilating the Orange Fruit to a deformable membrane (flavedo) filled with an internal incompressible juice, it was possible to estimate the compressive stress acting on the equatorial horizontal cross-section of the epicarp only and thus estimate the apparent modulus of elasticity of the Orange peel (=375 ± 33 kPa), and a burst pressure of 533 ± 103 kPa at a rupture strain ezR of 0.30 ± 0.03 for rind thicknesses ranging from 0.8 to 4.0 mm.

  • Orange Fruit rheometrical characterization using stress-relaxation tests
    2010
    Co-Authors: Federico Pallottino, Mauro Moresi, Stefano Giorgi, Paolo Menesatti
    Abstract:

    In this work the rheometrical behaviour of Tarocco-variety Orange Fruit was assessed under stress-relaxation testing. By analyzing the stress-relaxation data collected, at times 10 times greater than the loading period, the time course of the experimental dimensionless relaxation modulus (G*) was typical of a viscoelastic solid and was reconstructed by considering two Maxwell elements in parallel to an elastic spring element. As the engineering deformation (eE) or cross-head speed (Vt) was increased from 5 to 12% or from 5 to 15 mm s -1 , respectively, the dimensionless viscoelastic constants (Ai) were found to be approximately constant. Moreover, the elastic component responsible for the equilibrium residual stress represented about 60% of the initial relaxation modulus, this confirming that any Orange Fruit under study behaved as a linear viscoelastic solid, characterised by a unique relaxation time spectrum, for the time-scale and deformation range examined.

Lorenzo Zacarías - One of the best experts on this subject based on the ideXlab platform.

  • metabolic engineering of β carotene in Orange Fruit increases its in vivo antioxidant properties
    Plant Biotechnology Journal, 2014
    Co-Authors: Elsa Pons, Berta Alquézar, Ana Rodríguez, Patricia Martorell, Salvador Genovés, Daniel Ramón, María Jesús Rodrigo, Lorenzo Zacarías, Leandro Peña
    Abstract:

    Orange is a major crop and an important source of health-promoting bioactive compounds. Increasing the levels of specific antioxidants in Orange Fruit through metabolic engineering could strengthen the Fruit's health benefits. In this work, we have afforded enhancing the β-carotene content of Orange Fruit through blocking by RNA interference the expression of an endogenous β-carotene hydroxylase gene (Csβ-CHX) that is involved in the conversion of β-carotene into xanthophylls. Additionally, we have simultaneously overexpressed a key regulator gene of flowering transition, the FLOWERING LOCUS T from sweet Orange (CsFT), in the transgenic juvenile plants, which allowed us to obtain Fruit in an extremely short period of time. Silencing the Csβ-CHX gene resulted in Oranges with a deep yellow ('golden') phenotype and significant increases (up to 36-fold) in β-carotene content in the pulp. The capacity of β-carotene-enriched Oranges for protection against oxidative stress in vivo was assessed using Caenorhabditis elegans as experimental animal model. Golden Oranges induced a 20% higher antioxidant effect than the isogenic control. This is the first example of the successful metabolic engineering of the β-carotene content (or the content of any other phytonutrient) in Oranges and demonstrates the potential of genetic engineering for the nutritional enhancement of Fruit tree crops.

  • Metabolic engineering of β‐carotene in Orange Fruit increases its in vivo antioxidant properties
    Plant biotechnology journal, 2013
    Co-Authors: Elsa Pons, Berta Alquézar, Ana Rodríguez, Patricia Martorell, Salvador Genovés, Daniel Ramón, María Jesús Rodrigo, Lorenzo Zacarías, Leandro Peña
    Abstract:

    Summary Orange is a major crop and an important source of health-promoting bioactive compounds. Increasing the levels of specific antioxidants in Orange Fruit through metabolic engineering could strengthen the Fruit’s health benefits. In this work, we have afforded enhancing the b-carotene content of Orange Fruit through blocking by RNA interference the expression of an endogenous b-carotene hydroxylase gene (Csb-CHX) that is involved in the conversion of b-carotene into xanthophylls. Additionally, we have simultaneously overexpressed a key regulator gene of flowering transition, the FLOWERING LOCUS T from sweet Orange (CsFT), in the transgenic juvenile plants, which allowed us to obtain Fruit in an extremely short period of time. Silencing the Csb-CHX gene resulted in Oranges with a deep yellow (‘golden’) phenotype and significant increases (up to 36-fold) in b-carotene content in the pulp. The capacity of b-carotene-enriched Oranges for protection against oxidative stress in vivo was assessed using Caenorhabditis elegans as experimental animal model. Golden Oranges induced a 20% higher antioxidant effect than the isogenic control. This is the first example of the successful metabolic engineering of the b-carotene content (or the content of any other phytonutrient) in Oranges and demonstrates the potential of genetic engineering for the nutritional enhancement of Fruit tree crops.

  • stimulation of coloration and carotenoid biosynthesis during postharvest storage of navelina Orange Fruit at 12 c
    Postharvest Biology and Technology, 2012
    Co-Authors: Lourdes Carmona, Lorenzo Zacarías, María Jesús Rodrigo
    Abstract:

    Abstract The effect of storage temperature on color, carotenoid content and composition, and the expression of key carotenoid biosynthetic genes in Fruit of ‘Navelina’ Orange were evaluated. Fruit were harvested at two maturation stages, before color break (breaker stage) and with a light-Orange coloration (colored), and stored at 2 and 12 °C and 90–95% RH for up to 7 weeks. At the two maturation stages, storage at 12 °C considerably increased total carotenoid content and enhanced coloration in both flavedo and pulp. In Fruit stored at 2 °C, coloration and carotenoid content remained almost unchanged. The increase in peel color during storage at 12 °C was mainly related to an increment in the concentration of the reddish C30-apocarotenoid, β-citraurin, and to a minor extent to antheraxanthin. The content of β-cryptoxanthin, a β,β-xanthophyll with pro-vitamin A activity, increased two and three times in the pulp of breaker and colored Fruit, respectively, after 7 weeks of storage at 12 °C. The expression of the genes PSY (phytoene synthase), PDS (phytoene desaturase), ZDS (ζ-carotene desaturase), βLCY1 and βLCY2 (β-lycopene cyclase 1 and 2) and βCHX (β-carotene hydroxylase) increased during storage at 12 °C in the peel of Fruit at both maturation stages. At 2 °C, by contrast, expression of these genes was maintained or slightly declined. The pattern of changes in gene expression in the pulp of Orange Fruit stored at 12 °C was dependent of the ripening stage and not always related to the increment in carotenoid content and composition. Collectively, these results indicate that the stimulation of carotenoid biosynthesis during storage of ‘Navelina’ Orange Fruit at 12 °C improve not only peel and pulp coloration, but also pro-vitamin A activity of the flesh, and may then be a postharvest strategy to increase the nutritional and health-related benefits of citrus Fruit.

  • Stimulation of coloration and carotenoid biosynthesis during postharvest storage of 'Navelina' Orange Fruit at 12 ◦ C
    Postharvest Biology and Technology, 2012
    Co-Authors: Lourdes Carmona, Lorenzo Zacarías, María Jesús Rodrigo
    Abstract:

    Abstract The effect of storage temperature on color, carotenoid content and composition, and the expression of key carotenoid biosynthetic genes in Fruit of ‘Navelina’ Orange were evaluated. Fruit were harvested at two maturation stages, before color break (breaker stage) and with a light-Orange coloration (colored), and stored at 2 and 12 °C and 90–95% RH for up to 7 weeks. At the two maturation stages, storage at 12 °C considerably increased total carotenoid content and enhanced coloration in both flavedo and pulp. In Fruit stored at 2 °C, coloration and carotenoid content remained almost unchanged. The increase in peel color during storage at 12 °C was mainly related to an increment in the concentration of the reddish C30-apocarotenoid, β-citraurin, and to a minor extent to antheraxanthin. The content of β-cryptoxanthin, a β,β-xanthophyll with pro-vitamin A activity, increased two and three times in the pulp of breaker and colored Fruit, respectively, after 7 weeks of storage at 12 °C. The expression of the genes PSY (phytoene synthase), PDS (phytoene desaturase), ZDS (ζ-carotene desaturase), βLCY1 and βLCY2 (β-lycopene cyclase 1 and 2) and βCHX (β-carotene hydroxylase) increased during storage at 12 °C in the peel of Fruit at both maturation stages. At 2 °C, by contrast, expression of these genes was maintained or slightly declined. The pattern of changes in gene expression in the pulp of Orange Fruit stored at 12 °C was dependent of the ripening stage and not always related to the increment in carotenoid content and composition. Collectively, these results indicate that the stimulation of carotenoid biosynthesis during storage of ‘Navelina’ Orange Fruit at 12 °C improve not only peel and pulp coloration, but also pro-vitamin A activity of the flesh, and may then be a postharvest strategy to increase the nutritional and health-related benefits of citrus Fruit.

Paolo Menesatti - One of the best experts on this subject based on the ideXlab platform.

  • Assessment of quality-assured Tarocco Orange Fruit sorting rules by combined physicochemical and sensory testing
    Journal of the Science of Food and Agriculture, 2013
    Co-Authors: Federico Pallottino, Maria Carmela Lanza, Maria Concetta Strano, Francesca Antonucci, Paolo Menesatti, Mauro Moresi
    Abstract:

    BACKGROUND: The aim of this study was to extract a sorting rule for Tarocco Orange Fruit from several physicochemical and sensory tests performed on a marketable lot of 399 Tarocco Orange Fruits. RESULTS: The elastic tension at 5% strain (T5) was found to be linearly correlated (r = 0.65) with the MagnessTaylor (MT) index. Thus T5 was regarded as a non-destructive parameter quantifying Fruit firmness and used to categorise the aforementioned lot in three different firmness classes, high (HF), medium (MF) and low (LF). Only the MT index, Fruit rind thickness near the Fruit peduncle, lightness coefficient and yellow/blue hue component of the Orange flesh, as well as total soluble solid content, confirmed the validity of this discrimination at the significance level of 5%. Sensory professionals recognised the greater compactness (7 +/- 2) but lower ease of peeling (4 +/- 2) and segment separation (4 +/- 2) of the HF Oranges with respect to the corresponding sensory attributes of Orange Fruits grouped in the MF and LF classes. CONCLUSION: To limit the costly rejection of Tarocco Orange Fruit considered too soft, especially after long-term shipping, it would be reasonable to select only Fruits characterised by a compressive force or tension at 5% strain in the range 2341 N or 300540 N m1 respectively. (c) 2012 Society of Chemical Industry

  • Viscoelastic Properties of Tarocco Orange Fruit
    Food and Bioprocess Technology, 2011
    Co-Authors: Mauro Moresi, Federico Pallottino, Corrado Costa, Paolo Menesatti
    Abstract:

    In this work, the rheometrical behaviour of Tarocco Orange Fruit was assessed via stress–relaxation testing under constant engineering strain (ez) in the range of 5–20% of the initial Fruit height, each test being prolonged for 15 min and replicated 20 times. The time course of the experimental dimensionless relaxation modulus (G*) was typical of a viscoelastic solid and was reconstructed by considering two Maxwell elements in parallel to an elastic spring element. In a more restricted ez range (i.e. 5–10%), the dimensionless viscoelastic constants (Ai) were found to be approximately constant, the elastic component responsible for the equilibrium residual stress representing about 42% of the initial relaxation modulus. After any Orange Fruit had been submitted to stress–relaxation testing and decompressed for 5 min, it exhibited a practically negligible mass loss (0.04 ± 0.03%) and a permanent volume contraction rising from 1.7 ± 1.0% to 3.0 ± 0.9% as ez was increased from 5% to 10%. Thus, by tasting the Orange Fruit firmness at ez ≤5%, Fruit response, being of the viscoelastic type, is expected to give rise to nearly irrelevant deformations.

  • Assessment of the mechanical properties of Tarocco Orange Fruit under parallel plate compression
    Journal of Food Engineering, 2011
    Co-Authors: Federico Pallottino, Paolo Menesatti, Corrado Costa, Mauro Moresi
    Abstract:

    Abstract In this work the mechanical compressive properties of Orange Fruits of the Tarocco variety were assessed using a Universal Testing Machine, equipped with upper and lower plates made of transparent graduated Plexiglas® and three cameras positioned along the axis lines x, y and z. By submitting each Fruit to different engineering strains (ez) along the z-axis in the range of 3–21% of the initial Fruit height, the momentary contact area of each Fruit under testing was precisely determined by approximating its outline to a polygon and reconstructing it via the Elliptic Fourier Analysis, or an ellipse inscribed in a bounding box. Both estimates yielded no statistically significant difference and varied linearly with ez. Their prediction using the ASABE Standard Method (2008) , or assuming no variation in the volume of the Fruit undergoing compression, resulted be under- or over-estimated by 45% or 19%, respectively. Use of image analysis allowed the apparent Poisson’s ratio and modulus of deformability (EO) of the whole Orange Fruit to be estimated as equal to 0.16 ± 0.09 and 353 ± 3 kPa, respectively. By assimilating the Orange Fruit to a deformable membrane (flavedo) filled with an internal incompressible juice, it was possible to estimate the compressive stress acting on the equatorial horizontal cross-section of the epicarp only and thus estimate the apparent modulus of elasticity of the Orange peel (=375 ± 33 kPa), and a burst pressure of 533 ± 103 kPa at a rupture strain ezR of 0.30 ± 0.03 for rind thicknesses ranging from 0.8 to 4.0 mm.

  • Orange Fruit rheometrical characterization using stress-relaxation tests
    2010
    Co-Authors: Federico Pallottino, Mauro Moresi, Stefano Giorgi, Paolo Menesatti
    Abstract:

    In this work the rheometrical behaviour of Tarocco-variety Orange Fruit was assessed under stress-relaxation testing. By analyzing the stress-relaxation data collected, at times 10 times greater than the loading period, the time course of the experimental dimensionless relaxation modulus (G*) was typical of a viscoelastic solid and was reconstructed by considering two Maxwell elements in parallel to an elastic spring element. As the engineering deformation (eE) or cross-head speed (Vt) was increased from 5 to 12% or from 5 to 15 mm s -1 , respectively, the dimensionless viscoelastic constants (Ai) were found to be approximately constant. Moreover, the elastic component responsible for the equilibrium residual stress represented about 60% of the initial relaxation modulus, this confirming that any Orange Fruit under study behaved as a linear viscoelastic solid, characterised by a unique relaxation time spectrum, for the time-scale and deformation range examined.