Maria Luiza Lye Jomori

Intermittent warming in ‘Tahiti’ lime treated with an ethylene inhibitor

The storage of ‘Tahiti’ lime under low temperatures allows the marketing period to be extended, however, the loss of the green skin color and the occurrence of chilling injuries (CI) prevent such improvement to be achieved. The purpose of this work was to verify the efficiency of intermittent warming (IW) associated with the use of 1-methylcyclopropene (1-MCP) during the cold storage of ‘Tahiti’ lime. Fruit were treated for 12 h with 1-MCP at concentrations of 0 or 1.0 μl l−1 and then were stored at 5 °C. The fruit were submitted to IW (20 °C for 48 h every 7 days, 20 °C for 48 h every 14 days or 38 °C for 24 h every 14 days). Evaluations were carried out after 30, 60 and 90 days of storage (+3 days of simulated marketing at 20 °C). The occurrence of CI in the fruit was not observed after 30 days of storage, however, after 60 days of storage 40–58% of fruit kept continuously at 5 °C and 12.5–20% of fruit intermittent warmed showed CI. All fruit exhibited CI after 90 days. Warming fruit at 38 °C for 24 h every 14 days caused rot development, loss of green skin color, high respiratory rates, as well as accumulation of high levels of ethanol and acetaldehyde in fruit. Application of 1-MCP improved the maintenance of green color of skin.

Conservação refrigerada de lima ácida 'Tahiti': uso de 1-metilciclopropeno, ácido giberélico e cera

The storage of Tahiti lime under low temperatures allows the marketing period to be extended, however the loss of the green skin colour prevent such improvement to be achieved. The purpose of this research was to verify the efficiency of 1-methylcyclopropene (1-MCP) associated with the use of gibberellic acid (GA) and wax during the cold storage of Tahiti lime. The treatments used were: T1: fruit without treatment (control); T2: 1-MCP (1,0 i L. L-1) during 12 h at 20oC; T3: wax (0,1 mL per fruit); T4: GA (10 mg. L-1); T5: 1-MCP + wax; T6: 1-MCP + GA; T7: wax + GA; T8: 1-MCP + wax + GA; T9: T2 + new application of 1-MCP after 30 days of storage. Fruit were stored during 30 and 60 days at 10oC and 90% RH. The wax application was sufficient for the maintenance of green skin colour after 30 days of cold storage. 1-MCP maintain the green skin colour up to 30 days of cold storage, while new application of 1-MCP after this period does not present effect for the maintenance of colour. After 60 days of storage the fruit did not become marketable.

Efeitos de tratamentos térmicos aplicados sobre frutas cítricas armazenadas sob refrigeração

In the present study thermal treatments on,‘Valencia’ orange, ‘Murcott’ tangor and ‘Tahiti’ (temperature conditioning and intermittent warming) were applied lime. The following treatments were applied: T1: Fruits stored at 1°C (Controls); T2: Fast heating of the fruits in hot water at 53°C for 3 minutes and stored at 1°C; T3: Slow heating of the fruits in camera regulated at 37°C for 2 days, with subsequent storage at 1°C; and T4: Intermittent heating in cycles of 6 days at 1°C + 1 day at 25°C. Fruits were stored under low temperature (1°C) and 90-95% relative humidity (RH) during 90 days. Chilling injury incidence and changes in physical-chemical characteristics were evaluated every 15 days. Activity of catalase, glutathione reductase and ascorbate peroxidase was also determined. Intermittent warming was more efficient than temperature conditioning to reduce chilling injury. ‘Tahiti’ lime and ‘Murcott’ tangor supported up to 90 days of intermittent warming stored at 1°C, while control fruits showed chilling injury after 30 days (‘Tahiti’ lime) and 45 days (‘Murcott’ tangor). ‘Valencia’ orange was affected by chilling injury after 45 days of cold storage, and temperature conditioning has caused lower incidence of this disorder. The effect of thermal treatments can be related to the activity of

Inibição da ação do etileno retarda o desenvolvimento de injúrias de frio em tangor 'Murcott'

The blockage of ethylene-dependent signaling may affect the quality of tropical fruit in a positive or negative way after cold storage. Hence, the role of ethylene on chilling injury in tangor Murcott and the responses related to injuries resistance were the aims of this study. Fruit were treated for 12h with 500nL L-1 of 1 methylcyclopropene (1-MCP) or immersed into solutions containing 2000nL L-1 ethephon or salicylic acid for 5min before storage at 1°C for 90 days. As a control fruit were stored at 1°C. Chilling injury symptoms were anticipated and intensified when fruit were treated with ethephon or salicylic acid. On the other hand, the ethylene inhibition by 1-MCP delayed symptoms and resulted in the lowest injury index and percentage of fruit decay at the end of storage. At 45 days the superoxide dismutase (SOD) activity was intensified, however, in lower intensity in salicylic acid treated fruit. Afterwards, SOD activity decrease in all the treatments, though at 90 days the intensity was slightly superior to that at the initial 30 days of storage. During storage period it were not observed significantly alterations in putrescine (Put) and spermine (Spm) levels in flavedo tissues. In contrast, spermidine (Spm) levels were more affected by chilling stress.

Danos de frio e qualidade de frutas cítricas tratadas termicamente e armazenadas sob refrigeração

ABSTRACT- In this study, thermal treatments (temperature conditioning and intermittent warming) were applied in ´Valencia´ orange,´Murcott´ tangor and ´Tahiti´ lime stored in low temperature. Fruits were stored at 1 o C during 90 days and evaluate after every 15 daysaccording with the incidence of chilling injury and changes in physical-chemical characteristics. ‘Tahiti’ lime and ´Murcott’ tangorintermittently warmed could be stored up to 90 days at 1 o C, without the occurrence of chilling injury while control fruits showed chillinginjury after 30 days (´Tahiti’ lime) and after 45 days (´Murcott’ tangor). ´Valencia’ orange was affected by chilling injury af ter 45 days ofcold storage. In this cultivar, temperature conditioning has caused lower incidence of chilling injury. The intermittent warming is atreatment that can be used in these citrus cultivars without affecting the physical and chemical characteristics of fruits.Index terms: chilling injury, Citrus sp, temperature conditioning, intermittent warming.

Intermittent warming of 'Tahiti' lime to prevent chilling injury during cold storage

Storage of Tahiti limes (Citrus latifolia) at low temperature allows the marketing period to be extended. However, the loss of the green skin color and the occurrence of chilling injury (CI) prevent this extension. The purpose of this work was to verify the efficiency of intermittent warming (IW) in Tahiti lime quality maintenance during cold storage. Fruit were submitted to IW (20oC for 48 hours every 7 or 14 days or 38oC for 24 hours every 14 days) during cold storage at 5oC. Fruit were also stored at 5 and 10oC continuously. The evaluations were carried out after 30 and 60 days of storage (+ 3 days of simulated marketing at 20oC). CI occurrence on fruit was not verified after 30 days of storage. However, after 60 days of storage 60% of the fruit kept continuously at 5oC presented CI, while fruit intermittently warmed had 10 to 12.5% CI. Fruit stored at 10oC did not present CI, but they showed high degreening after 30 days of storage. Fruit warmed at 38oC for 24 hours every 14 days developed rot, loss of green skin color and vitamin C, high respiratory rates, as well as high levels of ethanol and acetaldehyde in the juice. Fruit can be stored at 5oC during 30 days, without risk of CI, while IW can be used to reduce CI after 60 days of storage.

Cold storage of 'Tahiti' lime treated with 1-methylcyclopropene

ABSTRACT: The storage of ‘Tahiti’ limes under low temperatures enables the extension of thecommercialization period. However the loss of the skin green color and the occurrence of chilling injuriesprevent such advantage. The purpose of this work was to verify the efficiency of 1-methylcyclopropene (1-MCP), an inhibition of ethylene action, during the cold storage of ‘Tahiti’ lime. Fruits were treated for 12hours with 1-methylcyclopropene at concentrations of 0 or 1.0 µL L -1 and then were stored at 5 or 10 o C for30, 60 and 90 days of storage (+ 3 days of simulated marketing at 20 o C). Application of 1-MCP conserved thecolor of stored fruits at 10 o C during 30 days. Fruits treated with 1-MCP and stored at 5 o C presented lessrespiration than non-treated fruits. High levels of ethanol and acetaldehyde were observed after 60 days innon-treated fruits. The occurrence of chilling injuries on fruits was not verified after a 30-day storage period,however after 60 days of storage, 40 to 58% of fruits kept at 5

Avaliação de biorreguladores no metabolismo secundário de beterrabas inteiras e minimamente processadas

The objective of this work was to evaluate the effects of bioregulators on some aspects of secondary metabolism of minimally processed and whole (without processing) beet roots. For the minimal processing, beet roots were peeled, sanitized, shredded (2 mm thick), rinsed and centrifuged. For whole beet roots, both leaves and stems were removed, and after the product was sanitized. The following treatments were applied: ethylene (1000 mL L-1), 1-MCP (300 nL L-1) and, salicylic acid (500 mg L-1). After treatments, beet roots were packed and stored at 5 oC during 10 days. Injuries that occurred during the minimal processing induced an increase of phenylalanine ammonia-lyase (PAL) activity in ethylene, 1-MCP and control treatments. However, salicylic acid decreased the activity of this enzyme. The treatments applied on whole and minimally processed beet roots did not have influence in total phenol and betalains concentration; however the betalains content was more than 50% lower in beet root minimally processed if compared to whole root.