Retarded Color Development Research Articles

Impact of salicylic acid, abscisic acid, and methyl jasmonate on postharvest quality and bioactive compounds of cultivated strawberry fruit

BACKGROUND: Strawberry is one of the most highly consumed fruits worldwide. However, it is highly a perishable fruit postharvest. OBJECTIVE: To assess the effect of dipping strawberry fruits after harvest in plant growth regulators to maintain postharvest quality. METHODS: Treatments tested were: 2 and 4 mM salicylic acid (SA), 0.25 and 0.50 mM abscisic acid (ABA) and methyl jasmonate at 0.25 and 0.50 mM (MeJA). Bioactive compounds and fungal growth were assessed over 12 days of storage at 4°C. RESULTS: Both concentrations of SA and MeJA significantly suppressed weight loss, decay and respiration rate and 0.50 mM ABA also reduced decay. Both concentrations of SA retarded color development, and total soluble solids content was enhanced by 0.50 mM ABA and MeJA treatments. The most effective treatments for preserving firmness were 0.25 mM MeJA and 4 mM SA. Reduction in loss of ascorbic acid and bioactive compounds during storage was achieved using the highest concentrations of SA, ABA, and MeJA. Fungal growth was suppressed by all treatments but the best treatment was MeJA at both concentrations. CONCLUSIONS: All three plant growth regulators reduce postharvest changes in strawberry but effects differ amongst the treatments.

NITRIC OXIDE FUMIGATION DELAYS MANGO FRUIT RIPENING

Hard mature green ‘Kensington Pride’ mango fruit were fumigated with 0, 5, 10, 20 and 40 µL.L−1 NO gas for 2 h and allowed to ripen at ambient temperature (21±1°C) to evaluate its effects on fruit ripening. NO-fumigation treatments significantly (P ≤ 0.05) suppressed ethylene production and respiration rates during fruit ripening. NO treatments (20 and 40 µL.L−1) retarded fruit softening (hand firmness) and delayed fruit ripening by 2-days as compared to all other treatments. NO-fumigated (40 µL.L−1) ripe fruit exhibited significantly higher pulp cohesiveness, springiness and chewiness as compared to all other treatments. NO fumigation retarded fruit color development (visual colour, L*, a*, b*, C*) and delayed the reduction of h° during fruit ripening. The concentrations of SSC, total sugars, glucose and fructose in the ripe fruit were significantly reduced in response to NO treatments. In conclusion, the postharvest fumigation of NO (20 µL.L−1) suppressed climacteric ethylene production, respiration rate, retarded colour development, softening consequently delayed mango fruit ripening.

Postharvest nitric oxide fumigation alleviates chilling injury, delays fruit ripening and maintains quality in cold-stored ‘Kensington Pride’ mango

We investigated the effects of postharvest nitric oxide (NO) fumigation (0, 5, 10, 20 and 40 μL L −1) on chilling injury (CI), ripening and quality of mango ( Mangifera indica L. cv. Kensington Pride) during fruit ripening at 21 ± 1 °C. The fruit had been cold-stored at 5 ± 1 °C for either 2 or 4 weeks. NO treatments (10, 20 and 40 μL L −1) significantly alleviated the CI index in cold-stored fruit during ripening. All NO fumigation treatments significantly suppressed ethylene production and respiration rates irrespective of the cold storage period. NO fumigation of higher than 5 μL L −1 significantly delayed fruit softening up to 2 d and retarded colour development, and fumigation after 2 and 4 weeks of cold storage significantly delayed the increase in total sugar and fructose concentrations at the full ripe stage. All NO fumigation treatments significantly increased tartaric and shikimic acids during ripening in 2- and 4-week cold-stored fruit, except for the 5 μL L −1 treatment in 2-week stored fruit. NO fumigation treatments did not significantly influence the concentrations of sucrose, glucose, total acid, citric, malic, fumaric, ascorbic acid, carotenoids in pulp and total antioxidant (in pulp and skin), as compared to non-fumigated fruit in both storage periods. Averaged over NO concentrations, 2 weeks of cold storage resulted in significantly higher mean concentrations of total sugar, sucrose, fructose, tartaric acid, malic acid, total carotenoids and total antioxidants (skin) than in 4-week stored fruit and the trend was the reverse for total acids, citric, shikimic, and fumaric acid. In conclusion, postharvest application of NO (10, 20 and 40 μL L −1) alleviated CI, delayed fruit colour development, softening and ripening as well as maintained quality through reduction of ethylene production and respiration during ripening in 2- and 4-week cold-stored fruit.

Fruit quality in ‘Cripp's Pink’ apple, especially colour, as affected by preharvest sprays of aminoethoxyvinylglycine and ethephon

‘Cripp's Pink’ apple grown in Western Australia often develops poor colour at commercial harvest resulting in economic losses. To determine if fruit colour could be improved without advancing ripening, ‘Cripp's Pink’ apple fruit on trees were sprayed with aminoethoxyvinylglycine (AVG) alone, ethephon alone, or AVG followed by ethephon. The experiments were conducted at two different locations in Western Australia in 2002 and 2003. Fruit sprayed with AVG alone had retarded colour development at harvest. However, ethephon applied after AVG enhanced percent red blush, anthocyanin concentration and reduced chlorophyll concentration in the fruit skin in both locations. These fruit had similar colour to those treated with ethephon alone. Internal ethylene concentration and fruit firmness were unaffected by the different treatments in 2002. However, in 2003 AVG with or without ethephon reduced internal ethylene concentration and maintained firmness compared to ethephon alone. In conclusion, AVG treatment alone delayed colour development and ripening of ‘Cripp's Pink’, while AVG application 5 weeks before harvest followed by an ethephon application 2 weeks later enhanced red colour at commercial harvest. This is, therefore, an effective tool for improving colour of ‘Cripp's Pink’ apples at commercial harvest without adversely affecting other fruit quality attributes.

Effect of the combined application of chitosan and carbonate salts on the incidence of anthracnose and on the quality of papaya during storage

SummaryThe potential of chitosan (1%) alone, or in combination with ammonium carbonate (3%) or sodium bicarbonate (2%), to reduce the incidence of anthracnose (Colletotrichum gloeosporioides) on papaya (Carica papaya L.) and maintain quality was investigated during storage at 13.5°C and 95% RH for 14 d, and for 2 d under simulated market conditions (25°C, 75% RH). Chitosan alone or in combination with sodium bicarbonate or ammonium carbonate significantly (P < 0.005) reduced the severity of anthracnose in both inoculated and naturally-infected fruit. The effect of chitosan with ammonium carbonate on the incidence and severity of anthracnose was greater than chitosan alone, or chitosan with sodium bicarbonate. Chitosan with ammonium carbonate significantly (P < 0.005) reduced the incidence of anthracnose in, and the recovery of C. gloeosporioides from naturally-infected fruit compared to control fruit. Eating quality was not affected by these post-harvest dip treatments. Chitosan with ammonium carbonate retained high fruit quality, significantly (P < 0.005) retarded colour development of skin and flesh, increased fruit firmness and reduced weight loss. Internal carbon dioxide concentrations increased in chitosan-coated fruit to reach 7% in chitosan and ammonium carbonate-treated fruit. Thus, chitosan combined with ammonium carbonate represents a commercially acceptable, economically viable and effective alternative for post-harvest control of anthracnose during storage of papaya.

Inhibition of ethylene action by 1-methylcyclopropene extends postharvest life of “Bartlett” pears

Abstract Preclimacteric European pears ( Pyrus communis L. cv. “Bartlett”) were untreated or treated with 0.4 μl l −1 1-methylcyclopropene (1-MCP) for 10 h at 20 °C and then kept at 20 °C, or stored at 1 °C for 30 or 60 days before transfer to 20 °C. Other lots were treated with 0.4, 0.8, 1.2, or 1.6 μl l −1 1-MCP after 30 or 60 days of storage at 1 °C. 1-MCP-treated pears kept at 20 °C had lower ethylene production and slower softening than untreated fruit. Treated fruit were more than 75 N firmer than control fruit after a 6 day storage period. Fruit color changes were also delayed by 1-MCP treatment. However, additional color sorting may be necessary to reduce variability in response of fruit to 1-MCP in commercial situations. 1-MCP-treated fruit had lower total glycosidase (α- and β- d -galactosidase, α- l -arabinofuranosidase, β- d -xylosidase, and β- d -glucosidase) activities. When 1-MCP was applied to fruit prior to cold storage (CS) at 1 °C, the synergistic interaction of cold and 1-MCP resulted in an extended postharvest life after transfer to room temperature, with concomitant delayed ethylene and respiratory level increases, retarded color development and retention of firmness. In contrast, application of 0.4–1.6 μl l −1 1-MCP after 30 or 60 days of cold storage did not affect most ripening indices. These findings point to the experimental and commercial utility of 1-MCP in “Bartlett” pear postharvest management.

Polysaccharide-based composite coating formulations for shelf-life extension of fresh banana and mango

The effects of four different composite coating formulations based on polysaccharides on maintaining quality and an extended shelf-life of banana and mango at 27±2 °C were investigated and compared with commercial Waxol-coated and uncoated fruits. The formulations consisted of modified starch, cellulose and chitosan, blended with a suitable lipid component and a wetting agent. Quality parameters measured included firmness, total soluble solids and titratable acidity. Physiological parameters measured were CO2 evolved and weight loss due to respiration and transpiration. The polysaccharide-based coatings displayed retarded colour development, lower acidity and greater firmness values compared to Waxol and control. CO2 evolution and loss in weight were also reduced significantly. The data were also subjected to PCA, to differentiate the characteristics of the five types of films. Chitosan-based coatings were much superior in prolonging the shelf-life and quality of banana and mango.

EFEITO DA ATMOSFERA CONTROLADA NA CONSERVAÇÃO DE TOMATES COLHIDOS EM ESTÁDIO INTERMEDIÁRIO DE MATURIDADE

Tomates (cv. "Agriset"), colhidos no estádio 2 de maturidade (menos de 10% da superfície vermelha), foram armazenados a 12 ± 0,5ºC em um sistema de fluxo contínuo sob diferentes concentrações de O2 (2%, 3% e 4%), CO2 (2%, 4% e 7%) e ar (controle). Após o armazenamento em atmosfera controlada (AC), a 12 ± 0,5ºC por 7 dias, os frutos foram transferidos para a temperatura de 20 ± 0,5ºC de modo a permitir o término do processo de amadurecimento em atmosfera normal. Quando os tomates começaram a perder a firmeza foram realizadas análises físicas e químicas. De um modo geral, o armazenamento de tomates no estádio 2 de maturidade em AC por 7 dias não alterou a qualidade final do produto - quando completamente maduro - estes frutos apresentaram mesma cor, acidez e conteúdo de açúcares e vitamina C do que aqueles armazenados em ar durante todo o período. Somente os tratamentos 2% e 3% O2 mostraram um maior atraso no desenvolvimento da cor após os 7 dias a 12 ± 0,5ºC. No entanto, o tempo de armazenamento, 7 dias, não foi suficiente para retardar a taxa de amolecimento dos frutos armazenados sob AC.

Regulation of the ripening of tomato pericarp discs by GA3 and divalent cations

We have used a tomato (Lycopersicon esculentum Mill.) pericarp disc system to study the inhibition of ripening caused by diazocyclopentadiene (DACP), gibberellic acid (GA3) and calcium (CaCl2), and to compare their modes of action. Treatment of discs with 1‐aminocyclopropane carboxylic acid (ACC) accelerated their ripening while DACP treatment eliminated ripening in the absence or presence of a treatment with the ethylene precursor. Both GA3 and calcium retarded color development and tissue softening. Calcium delayed the onset of the climacteric rise in respiration and ethylene evolution, but GA3 had no consistent effect in this respect. The different modes of action of the two inhibitors were emphasized by the synergistic effect on inhibition of ripening obtained when both were simultaneously applied. Inhibition of color development and softening was also achieved by applying other divalent cations such as strontium and barium. However, no such effect was observed with manganese or with the monovalent cations potassium and sodium. We concluded that calcium inhibition of ripening is not specific and is not necessarily mediated by the calcium calmodulin complex.

Postharvest Use of Sucrose Polyesters for Extending the Shelf‐life of Stored ‘Golden Delicious’ Apples

ABSTRACTThe post‐storage uses of a sucrose‐fatty acid polyester (SPE) formulation, commercial fruit wax and a combination of both were investigated on ‘Golden Delicious’ apples after fruit were removed from both controlled atmosphere (CA) and refrigerated storage. Quality parameters measured included color (skin and internal), firmness, soluble solids and titratable acidity. Physiological parameters measured were carbon dioxide and ethylene concentrations both evolved and internal. Refrigerated stored apples, treated with SPE, displayed retarded color development, higher acid and greater firmness values compared to controls. CA stored, treated apples possessed similar attributes but no firmness retention. Ethylene evolution was reduced in SPE‐coated apples. In comparison to control apples, an internal accumulation of carbon dioxide and a reduction in ethylene was observed.

Influence of Carbon Dioxide on Postharvest Ripening and Deterioration of Tomatoes1

Abstract Turning tomatoes (Lycopersicon esculentum Mill.) were held at 20°C and exposed to ambient, 5, 10, 20, 40 and 60% CO2 with 21 ± 1% O2. C2H4 evolution was rapidly reduced when fruits were exposed to CO2. In 5, 10 and 20% CO2, C2H4 evolution continued to decline with increasing duration of exposure but after 4 days in 40 and 60% CO2, C2H4 evolution increased probably because of injury. Maximum retardation of color development occurred while exposed to between 10 and 20% CO2. After removal of CO2, color development advanced rapidly and after 4 days in air, color of fruits that had been exposed to 5 and 10% CO2 was indistinguishable from that of fruit held continually in air. Color of fruits exposed to 20, 40, and 60% CO2 never reached color of fruits held only in air, in addition, exposure to these concentrations reduced subsequent salability due to enhanced mold growth, uneven ripening, and watersoaking. Intermittent exposures to 20% CO2 and air caused rapid fluctuation of C2H4 evolution and retarded color development. CO2 was not effective in inhibiting wound induced C2H4 evolution.