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Jorge F. Vélez-ruiz - One of the best experts on this subject based on the ideXlab platform.
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Effect of Solids Concentration on the Physicochemical and Flow Properties of Cactus Pear Juices of Two Varieties (Opuntia ficus-indica and Opuntia streptacantha)
Food and Bioprocess Technology, 2017Co-Authors: Cecilia Díaz-lima, Jorge F. Vélez-ruizAbstract:Juices from two varieties of Cactus pear, a green ( Opuntia ficus-indica ) and a red ( Opuntia streptacantha ), were obtained and concentrated by evaporation. Both fruit varieties and their juices at different concentrations were characterized. Green Cactus Pears had significantly higher amount of pulp than red Cactus Pears; the peel of O. ficus-indica represented only 38 versus 52 % of the fruit for the O. streptacantha . Both varieties had no significant differences on moisture, density, pH, and titratable acidity, in contrary to soluble solids. Juice was concentrated under vacuum conditions to reach a final concentration of 42, 53–55, and 58–60 °Brix, respectively, and stored under refrigeration (10 °C) during 4 weeks. Physicochemical properties of the Pears and juices were determined as fresh items (time zero) and every week for the concentrate juices through storage; similarly, flow parameters were measured at 10 and 25 °C. Concentrate density (1160–1283 kg/m^3) was mainly affected by final soluble solids, while pH and acidity were affected differently depending on the variety. Concentrated juices at 42 °Brix were considered with Newtonian behavior with a viscosity of 2–22 mPa s, while those at higher concentrations were of pseudoplastic nature ( n 69 mPa s^n). Power Law model fitted better the flow behavior than Herschel-Bulkley model of concentrates of both varieties. Temperature, solid concentration, and/or storage time affected the consistency coefficient ( K ) and flow index ( n ) depending on the Cactus pear variety. Overall, those concentrated juices from O. streptacantha were more stable and exhibited lower apparent viscosity.
Arno Hugo - One of the best experts on this subject based on the ideXlab platform.
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Mucilage powder from Cactus Pears as functional ingredient: influence of cultivar and harvest month on the physicochemical and technological properties
Journal of Food Science and Technology, 2019Co-Authors: Alba Toit, Maryna Wit, Hermanus J. Fouché, Marli Taljaard, Sonja L. Venter, Arno HugoAbstract:Cactus pear mucilage is a novel, inexpensive hydrocolloid that is used to add nutrients, body and texture to functional food products. However, varied physicochemical and technological properties of powders when cultivar and harvest month of cladodes differ could lead to differentiation in the application of mucilage powders. To that end, three Opuntia ficus - indica (Algerian, Morado and Gymno-Carpo) cultivars and one Opuntia robusta (Robusta) cultivar were harvested over a 6 month period and evaluated in this study. February mucilage powders were the most porous with highest oil absorption and oil holding capacity, lowest water holding and swelling capacity, and lowest ability to increase viscosity. August mucilage powders had the smallest impermeable particles, highest water holding and hydrophobic properties, as well as the best emulsifying capacity, stability and ability to increase viscosity. Opuntia robusta produced brighter, darker green, more viscous mucilage while Opuntia ficus - indica powders were dull, light yellow-green with a lower viscosity and emulsifying capacity. Overall, the mucilage powders were easy to pour and free-flowing yet were microbiologically safe due to low water activity and pH levels. Robusta mucilage was successfully applied in mayonnaise products to replace up to 50% egg yolk and 30% oil. It was concluded that mucilage powders might contribute to the textural and nutritional quality of food products. The acceptance of mucilage powder as an active functional and nutraceutical food ingredient will also lead to the development of Cactus as a commercially viable crop in arid and semi-arid areas where few other crops can survive.
Cecilia Díaz-lima - One of the best experts on this subject based on the ideXlab platform.
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Effect of Solids Concentration on the Physicochemical and Flow Properties of Cactus Pear Juices of Two Varieties (Opuntia ficus-indica and Opuntia streptacantha)
Food and Bioprocess Technology, 2017Co-Authors: Cecilia Díaz-lima, Jorge F. Vélez-ruizAbstract:Juices from two varieties of Cactus pear, a green ( Opuntia ficus-indica ) and a red ( Opuntia streptacantha ), were obtained and concentrated by evaporation. Both fruit varieties and their juices at different concentrations were characterized. Green Cactus Pears had significantly higher amount of pulp than red Cactus Pears; the peel of O. ficus-indica represented only 38 versus 52 % of the fruit for the O. streptacantha . Both varieties had no significant differences on moisture, density, pH, and titratable acidity, in contrary to soluble solids. Juice was concentrated under vacuum conditions to reach a final concentration of 42, 53–55, and 58–60 °Brix, respectively, and stored under refrigeration (10 °C) during 4 weeks. Physicochemical properties of the Pears and juices were determined as fresh items (time zero) and every week for the concentrate juices through storage; similarly, flow parameters were measured at 10 and 25 °C. Concentrate density (1160–1283 kg/m^3) was mainly affected by final soluble solids, while pH and acidity were affected differently depending on the variety. Concentrated juices at 42 °Brix were considered with Newtonian behavior with a viscosity of 2–22 mPa s, while those at higher concentrations were of pseudoplastic nature ( n 69 mPa s^n). Power Law model fitted better the flow behavior than Herschel-Bulkley model of concentrates of both varieties. Temperature, solid concentration, and/or storage time affected the consistency coefficient ( K ) and flow index ( n ) depending on the Cactus pear variety. Overall, those concentrated juices from O. streptacantha were more stable and exhibited lower apparent viscosity.
P Inglese - One of the best experts on this subject based on the ideXlab platform.
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reducing postharvest decay in Cactus Pears by dip treatment with imazalil or azoxystrobin
Acta Horticulturae, 2019Co-Authors: Salvatore Daquino, P Inglese, Giorgia Liguori, Maria Judith Ochoa, A PalmaAbstract:Postharvest decay in Cactus pear is a minor problem in fruit marketed directly after harvest, while it may represent a major cause of losses when fruit are cold stored or subjected to cold quarantine treatments. Unfortunately, to date, no postharvest fungicide has been registered to control postharvest decay of Cactus Pears. Thus, the objective of this study was to evaluate the efficacy of two globally known fungicides, imazalil (IMZ) and azoxystrobin (AZO), registered for postharvest treatment of various fresh produce species, to control decay on Cactus Pears. Second-crop Cactus Pears ‘Gialla’ fruits were dipped in 500 mg L(‑1) IMZ or AZO and stored at 1 or 8°C and 90-95% RH for 2 or 3 weeks, respectively, plus 1 additional week at 20°C and 55‑60% RH to simulate retail conditions. At the end of storage, decay incidence ranged between 16 and 23% in control fruit, while the percentage of losses in treated fruit ranged between 3% (IMZ) and 5% (AZO). Although no significant difference was detected between the two fungicides in terms of percentage of rotten fruit, IMZ seemed to be more active than AZO in controlling Penicillium decay. Both chemicals ameliorated fruit responses to chilling injury, but a slightly higher decline in freshness, associated with faster transpiration activity, occurred in AZO-treated fruit. Based on these results, considering the complexity of the registration process of new chemicals and the easier procedure required for manufacturers to apply for extension of use of already registered pesticides, both chemicals could be good candidates as potential fungicides to control postharvest disease of Cactus Pears.
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the influence of harvest period and fruit ripeness at harvest on minimally processed Cactus Pears opuntia ficus indica l mill stored under passive atmosphere
Postharvest Biology and Technology, 2015Co-Authors: Alessio Allegra, Giuseppe Sortino, G Miciletta, M Riotto, Teresa Fasciana, P IngleseAbstract:Abstract The aim of this study was to investigate the effect of (a) harvest season (summer and late crop), (b) fruit ripening stage at harvest and (c) time of storage, on the quality of minimal processed Cactus pear ( Opuntia ficus-indica ). Fresh cut peeled Cactus Pears harvested at commercial harvest stage or when ripe on tree in August (summer crop) and October (late crop), were stored for 3, 5, 7 and 12 d at 5 °C and 95% RH in polyethylene terephthalate ( PET) packages under passive atmosphere conditions. Visual quality and crunchiness score, flesh color, microbiological analysis, total soluble solids (TSS), total acidity (TA), total phenolics, ascorbic acid and β-carotene contents were measured. TSS content in fruit flesh did not change during storage, but late crop fruit harvested fully ripe had the highest content. The CO 2 concentration inside the package was higher for summer than late fruit and for fully ripe fruit than commercial harvest stage. Fresh cut summer Cactus Pears lost their marketability and crunchiness after 3 d, while those from the late crop retained good marketability after 5 or 7 d at 5 °C, depending on their ripeness stage at harvest. Fresh cut fruit of the summer crop had twice the ascorbic acid content than late cop fruit until 5 d after storage. Fully ripe fresh cut fruit of the summer crop had the lowest β-carotene content. The mesophilic aerobic microorganisms did not change significantly with treatments, until 12 d after storage, when fully ripe fresh cut fruit had the highest count. Mold content was higher in fully ripe than in fruit harvested at commercial ripeness. Ultimately, late fruit, manually peeled and stored at 5 °C under passive atmosphere, retained their original quality longer than fully ripe fruit of the same season or summer fruit harvested at either ripeness stage.
H A Snyman - One of the best experts on this subject based on the ideXlab platform.
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growth rate and water use efficiency of Cactus Pears opuntia ficus indica and o robusta
Arid Land Research and Management, 2013Co-Authors: H A SnymanAbstract:There is a lack of knowledge on water-use efficiency (WUE) of Cactus pear under field conditions for a full growing season. Therefore, the growth rate and WUE (relationship between evapotranspiration and growth) was quantified for one to four-year-old Opuntia ficus-indica (L.) Miller (cultivar Morado, green cladode) and O. robusta Wendl. (cultivar Monterey, blue cladode) plants in a semi-arid climate. Although not significant (p > 0.05), evapotranspiration of O. ficus-indica was higher than that of O. robusta over the four growing seasons. The water content in the cladodes ranged between 88.02 and 88.21% for O. ficus-indica and for O. robusta between 87.23 and 87.52% (p < 0.05). The mean cladode fresh mass for the four growing seasons were 1,299 g cladode−1 for O. ficus-indica and 1,091 g cladode−1 for O. robusta (p < 0.05). The four-year-old plants produced in total as much as 9,665 and 8,378 kg dry mass (DM) ha−1 for O. ficus-indica and O. robusta, respectively. The relative growth rate and WUE of O. fi...
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root studies on Cactus Pears opuntia ficus indica and o robusta along a soil water gradient
Haseltonia, 2007Co-Authors: H A SnymanAbstract:Abstract Due to the regular occurrence of drought in southern Africa, there is need for more research on drought tolerant fodder plants such as Opuntia species. The influence of different water applications was evaluated in terms of root and cladode mass, root length, and water-use efficiency for one-year-old Cactus pear plants of the species Opuntia ficus-indica (L.) Miller (Morado cultivar) and O. robusta Wendl. (Monterey cultivar). One-year-old cladodes were planted in pots (210 mm diameter × 550 mm deep soil) and grown in the greenhouse at day/night temperatures of 25–30/15–18°C. The water treatments applied were 0–25%, 25–50%, 50–75% and 75–100% depletion of total plant available water. Water-use efficiency (WUE) was defined as the cladode or root dry-mass production per unit of water used. Root mass decreased and root length increased significantly (p < 0.01) for both species with water stress. Due to the finer root system of O. robusta, the root mass was smaller than that of O. ficus-indica. In con...
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root distribution with changes in distance and depth of two year old Cactus Pears opuntia ficus indica and o robusta plants
South African Journal of Botany, 2006Co-Authors: H A SnymanAbstract:Abstract Opuntia is a drought tolerant crop and even the smallest amount of water is absorbed efficiently through the shallow and horizontally spread root system. However, there is a lack of knowledge on the root dynamics of Cactus pear for sustainable production of fodder and fruit in the drier areas. This study, conducted during the 2003/2004 growing season on two-year-old Opuntia ficus-indica (L.) Miller (cultivar Morado–green cladode) and O. robusta Wendel. (cultivar Monterey–blue cladode) plants in the field was therefore aimed at quantifying root distribution with distance and depth from the stem. Root growth was expressed in terms of both mass and length, and water-use efficiency (WUE) was defined as the cladode dry mass production per unit of evapotranspiration. In both species most roots were concentrated in the first 150 mm soil layer. After only two growing seasons the roots spread as far as 2.5 m from the stem for both species. The total root dry weight production calculated per plant up to a depth of 1200 mm, was 239 and 316 g per plant or kg ha − 1 for O. ficus-indica and O. robusta respectively. The thickest roots developed directly from the planted cladode and were 9.1 mm thick for O. ficus-indica and 6.3 mm for O. robusta . Opuntia robusta showed a finer root system than that of O. ficus-indica . After two growing seasons 3407 and 2702 kg ha − 1 aboveground dry mass was produced by O. ficus-indica and O. robusta respectively. The WUE of O. ficus-indica (6.52 kg ha − 1 mm − 1 ) was significantly higher than that of O. robusta (5.39 kg ha − 1 mm − 1 ). The roots comprised only 11% of the total biomass for O. robusta and 7% for O. ficus-indica . Such root adaptations of this species are in addition to the classical physiological and structural modifications of CAM plants to tolerate prolonged drought.
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a greenhouse study on root dynamics of Cactus Pears opuntia ficus indica and o robusta
Journal of Arid Environments, 2006Co-Authors: H A SnymanAbstract:Abstract Over the last 10 years a great interest in spineless Cactus pear was shown in the drier areas in terms of both fresh fruit and fodder production. However, there is a lack of knowledge on quantitative data on root dynamics of these plants needed to fully understand its potential under water limiting conditions. This study aimed at quantifying the effects of water stress on the growth of tap roots, side roots and rain roots of the species Opuntia ficus-indica (L.) Miller (cultivar Morado—green cladode) and O. robusta Wendl. (cultivar Monterey—blue cladode). One-year-old cladodes were planted in root boxes and pots (2002/2003 season) that were kept in the greenhouse at day/night temperatures of 25–30 °C/15–18 °C. Placing the cladodes flat on the soil, more areoles came in contact with the soil and therefore more roots developed in both species with an average of only 3.4% areole complexes not rooting. Each areole complex formed on average 3 roots. The highest daily tap root growth was 42 and 36 mm for O. ficus-indica and O. robusta , respectively. Tap root growth increased in the morning with water stress for both species but decreased in the afternoon. Side root growth increased with water stress, with that of O. robusta more per tap root than O. ficus-indi ca. O. robusta showed a finer root system than O. ficus-indica . The side roots grew as much as 8 and 5 mm per day for O. ficus-indica and O. robusta , respectively. Whitish rain roots developed on the established roots within the first hour after rewetting the soil and grew for only 3 days. Rain roots grew up to 7 and 5 mm within a day for O. ficus-indica and O. robusta, respectively. Considering all studied aspects of their roots systems, O. robusta apPears to be better adapted to drought (less sensitive to water stress) than O. ficus-indica .
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a case study on in situ rooting profiles and water use efficiency of Cactus Pears opuntia ficus indica and o robusta
Journal of The Professional Association for Cactus Development, 2005Co-Authors: H A SnymanAbstract:Root distribution of Cactus pear with distance from the mother plant and depth was determined in the field for one-year-old Opuntia ficus-indica (L.) Miller (cultivar Morado – green cladode) and O. robusta Wendl. (cultivar Monterey – blue cladode) in a semiarid climate. The roots were expressed in terms of root mass, root length and root thickness. In addition, the evapotranspiration water-use efficiency (cladode dry-mass production per unit of evapotranspiration) was quantified for these two spineless Cactus pear species during the 2002/2003 growing season. In both species most roots were concentrated over the first 100 mm soil layer. After only one growing season of establishment the roots spread as far as 1.7 m and 1.8 m from the stem for O. robusta and O. ficus-indica, respectively. The root mass, root length, and root thickness decreased (P < 0.05), as expected, with depth and distance. The total root mass per plant, calculated for all depths were 107.5 and 131.6 g m -2 for O. ficus-indica and O. robusta, respectively. The root length and root mass relationship showed that a root mass of 1 g m -2 was equal to a root length of 3.17 and 3.79 m m -2 for O. ficus-indica and O. robusta, respectively. O. robusta showed a finer root system than that of O. ficus-indica. The evapotranspiration water-use efficiency for the two species ranged between 1.19 to 1.57 kg DM ha -1 mm -1 for O. robusta and O. ficus-indica respectively. The roots composed only 21% and 13% of the total plant biomass for O. robusta and O. ficus-indica, respectively. In the one-year-old plants no deep root system occurred in both species and was only characterized by a shallow horizontally spreading root system. These above-mentioned root characteristics of the Cactus pear make it more appropriate for arid and semiarid crop production. The marginal drier areas with shallow soils can, therefore, be utilised to their full potential by the Cactus-pear plant.
