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Effect of gum arabic as an edible coating on antioxidant capacity of tomato (Solanum lycopersicum L.) fruit during storage.

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Effect of gum arabic as an edible coating on antioxidant capacity of tomato (Solanum lycopersicum L.) fruit during storage.

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Abstract

Coating of tomato fruit with gum arabic has been found to delay the ripening process and maintain the antioxidant capacity. Gum arabic in aqueous solutions of 5, 10, 15 and 20% was applied as an edible coating to green-mature tomatoes which were stored at 20 °C and 80–90% RH for 20 days. Fruit coated with 10% gum arabic delayed the ripening process by slowing down the rate of respiration and ethylene production and also maintained total antioxidant capacity, lycopene content, total phenolics and total carotenoids during storage as compared to the uncoated control and fruit treated with 5% gum arabic concentration. The results suggest that by using 10% gum arabic as an edible coating, the ripening process of tomatoes can be delayed and the antioxidant can be preserved for up to 20 days during storage at 20 °C without any negative effects on postharvest quality.

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... Edible coating is an effective technique to modify internal atmosphere of vegetables to slow metabolic processes. A coating solution con- taining 10% gum arabic helps maintain the phenolic content for a longer period than uncoated tomato fruit ( Ali et al., 2013). Loss of phenolics in uncoated tissues was due to senescence and breakdown of cell structure. ...
... With application of coatings, respiration rate can be slowed, and antioxidant activity can be maintained for a longer storage period. Antioxidant activity in tomatoes is retained longer when coated with 10% gum arabic, as the ripening process is retarded by delaying biochemical and physiological changes ( Ali et al., 2013). Similar results were observed for raddish and carrot shred when coated with chitosan (0.2%) compared to uncoated tissue with the same storage conditions ( Pushkala et al., 2012Pushkala et al., , 2013). ...
... During ripening chlorophyll is degraded and forma- tion of other pigments including lycopene and anthocyanins occurs ( Petriccione et al., 2015). Edible coating slows ripening rate, delaying color change compared to uncoated tissue ( Ali et al., 2013). Chitosan coating delayed the color change in tomatoes better than in controls by slowing respiration rate ( Abebe et al., 2017). ...
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... Many of the exudate gums, such as acacia and karaya and seed/mucilaginous gums such as guar and locust bean, are known for their commercial applications all over the world [76]. Acacia species-derived Arabic gum is the most industrially employed polysaccharide because of its film-forming, encapsulation properties and unique emulsification [17,79]. The Arabic gum is composed of galactose, rhamnose, arabinose, and glucuronic acid [80], it has been used in food, cosmetics and pharmaceutical industries [81]. ...
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Coating bananas with TAL Pro-long modified their internal atmospheres by reducing the permeability of the fruit skin to gases. Permeability of control fruit to carbon dioxide was greater than that to oxygen and ethylene, and this differential permeability was enhanced by coating. This resulted in a depression of the fruit's internal oxygen content which affected ripening without a concomitant increase in the levels of carbon dioxide which could have proved toxic. The skins of coated fruit lost chlorophyll more slowly than controls and there was a small effect on the accumulation of monosaccharides in the fruit pulp. These effects were associated with depressed rates of respiration and ethylene production in the coated fruit, but the accumulation of acetaldehyde and ethanol was no more rapid than in controls.
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Modified atmospheres (MA), i.e., elevated concentrations of carbon dioxide and reduced levels of oxygen and ethylene, can be useful supplements to provide optimum temperature and relative humidity in maintaining the quality of fresh fruits and vegetables after harvest. MA benefits include reduced respiration, ethylene production, and sensitivity to ethylene; retarded softening and compositional changes; alleviation of certain physiological disorders; and reduced decay. Subjecting fresh produce to too low an oxygen concentration and/or to too high a carbon dioxide level can result in MA stress, which is manifested by accelerated deterioration. Packaging fresh produce in polymeric films can result in a commodity-generated MA. Atmosphere modification within such packages depends on film permeability, commodity respiration rate and gas diffusion characteristics, and initial free volume and atmospheric composition within the package. Temperature, relative humidity, and air movement around the package can influence the permeability of the film. Temperature also affects the metabolic activity of the commodity and consequently the rate of attaining the desired MA. All these factors must be considered in developing a mathematical model for selecting the most suitable film for each commodity.
Article
In view of the persisting uncertainty concerning possible mechanisms by which high vegetable and fruit intake decreases cancer risk, foods with divergent values for potentially important micronutrients are a priority for investigation. Tomatoes are low in beta-carotene, but high in lycopene, an active antioxidative agent. In order to assess the effect of tomatoes on risk of cancers of the digestive tract, data were analyzed from an integrated series of case-control studies conducted between 1985 and 1991 in northern Italy, where tomato intake is high but, also, heterogeneous. The overall dataset included the following histologically confirmed cancer cases: oral cavity and pharynx, 314; esophagus, 85; stomach, 723; colon, 955; and rectum, 629; and a total of 2,879 controls admitted to hospital for acute non-neoplastic or non-digestive conditions, unrelated to long-term dietary modifications. Multivariate odds ratios (OR) and 95% confidence interval (CI) for subsequent quartiles of intake of raw tomatoes were derived, after allowance for age, sex, study center, education, smoking and drinking level, and tertile of total caloric intake. There was a consistent pattern of protection for all sites (OR in the upper quartile ranging between 0.4 and 0.7), most notably for gastrointestinal neoplasms. All trends in risk were highly significant. The beneficial effect of raw tomatoes in this population may be partly due to the fact that they constitute perhaps the most specific feature of the Mediterranean diet. However, if it is true that tomatoes protect against digestive-tract cancers, this is of interest from both a scientific and a public health viewpoint.
Article
A simple, automated test measuring the ferric reducing ability of plasma, the FRAP assay, is presented as a novel method for assessing "antioxidant power." Ferric to ferrous ion reduction at low pH causes a colored ferrous-tripyridyltriazine complex to form. FRAP values are obtained by comparing the absorbance change at 593 nm in test reaction mixtures with those containing ferrous ions in known concentration. Absorbance changes are linear over a wide concentration range with antioxidant mixtures, including plasma, and with solutions containing one antioxidant in purified form. There is no apparent interaction between antioxidants. Measured stoichiometric factors of Trolox, alpha-tocopherol, ascorbic acid, and uric acid are all 2.0; that of bilirubin is 4.0. Activity of albumin is very low. Within- and between-run CVs are <1.0 and <3.0%, respectively, at 100-1000 micromol/liter. FRAP values of fresh plasma of healthy Chinese adults: 612-1634 micromol/liter (mean, 1017; SD, 206; n = 141). The FRAP assay is inexpensive, reagents are simple to prepare, results are highly reproducible, and the procedure is straightforward and speedy. The FRAP assay offers a putative index of antioxidant, or reducing, potential of biological fluids within the technological reach of every laboratory and researcher interested in oxidative stress and its effects.
Article
Ethylene triggers the ripening process of tomato affecting the storage durability and shelf life (loss of quality) and inducing fruit decay. In this paper, an active packaging has been developed on the basis of the combination of modified atmosphere packaging (MAP) and the addition of granular-activated carbon (GAC) alone or impregnated with palladium as a catalyst (GAC-Pd). A steady-state atmosphere was 4 and 10 kPa for O2 and CO2 in control packages, while it was 8 and 7 kPa for O2 and CO2 in treated ones. The addition of GAC-Pd led to the lower ethylene accumulation inside packages, while the higher was obtained in controls. The parameters related to ripening showed that treated tomatoes exhibited a reduction in color evolution, softening, and weight loss, especially for GAC-Pd treatment. Moreover, these treatments were also effective in delaying tomato decay. After sensorial panel, tomatoes treated with GAC-Pd received the higher scores in terms of sweetness, firmness, juiciness, color, odor, and flavor. Results from the GC-MS analysis of the MAP headspace showed that 23 volatile compounds were identified in control packages, with these volatiles being significantly reduced in MAP-treated packages, which was correlated to the odor intensity detected by panelists after bag opening.
Effects of edible coatings on the shelf-lifeandqualityofAnnaapple(MalusdomesticaBorkh)duringcoldstorage
  • El
  • A M Anany
  • G F A Hassan
  • F M Ali
El-Anany, A.M., Hassan, G.F.A., Rehab Ali, F.M., 2009. Effects of edible coatings on the shelf-lifeandqualityofAnnaapple(MalusdomesticaBorkh)duringcoldstorage. Journal of Food Technology 7, 5–11
  • A Ali
A. Ali et al. / Postharvest Biology and Technology 76 (2013) 119–124
United States Standard for Grades of Fresh Tomatoes. US Department of Agriculture
USDA, 1991. United States Standard for Grades of Fresh Tomatoes. US Department of Agriculture, Agricultural Marketing Service, Washington, DC.