Ethanol reduces ripening of 'Royal Gala' apples stored in controlled atmosphere

Abstract

This work aims at evaluate ethanol effect of acetaldehyde application in post-storage quality of 'Royal Gala' apples maintenance, and to compare them with consolidated storage techniques. Thus two experiments were performed during the years of 2008 and 2009. In the fi rst experiment (2008), the application of ethanol, acetaldehyde or 1-MCP and ethylene scrubbing were tested. Fruits were stored in controlled atmosphere (CA) with 1.0kPa O 2 and 2.0kPa CO 2 at 0.5°C. In the second experiment (2009), the treatments tested were ethanol application combined or not with low relative humidity (LRH) and LRH alone. In this experiment, apples were stored in CA with 1.2kPa O 2 + 2.5kPa CO 2 at 0.5°C. After eight months of storage, 0.5 mL ethanol kg -1 apples month -1 or 0.25 mL acetaldehyde kg -1 apples month -1 increased mealiness, fl esh browning, and decays incidence and reduced fl esh fi rmness. In contrast, 0.3 mL ethanol kg -1 apples month -1, tested on second experiment, prevented fruit softening and decreased ACC oxidase activity and ethylene production. Although lower relative humidity was not effi cient in maintaining poststorage quality, it enhanced the positive effect of ethanol application at 0.3 mL kg -1 apples month -1 .

Ethanol vapor treatment of ‘Laetitia’ plums stored under modified atmosphere

“…The fruits respiration rate was not affected by the ethanol doses (data not shown); however, some studies show that non-toxic concentrations of exposure to ethanol may reduce it (WEBER et al, 2016).…”

“…According to Bai et al (2004), ethanol action mechanism is related to the endogenous concentration of acetaldehyde, which is a biologically active factor that affects the production of ethylene. Weber et al (2016) found that the production of acetaldehyde in apples after eight months of storage reduced ethylene synthesis in the fruits. The acetaldehyde present in tissue, resulted from the conversion of ethanol or from the application of acetaldehyde itself, seems to be a determining factor in the inhibition of ripening, characterized by an increase in the synthesis of ethylene (BRACKMANN et al, 2009), as it acts by directly inhibiting the action of enzymes ACC synthase and ACC oxidase, which act in the conversion of ACC into ethylene (BOTH et al, 2014).…”

Extremely low oxygen partial pressures for the storage of ‘Royal Gala’ apple

“…Moreover, this enzyme is responsible for ethylene synthesis and is activated or inhibited depending on the concentration of the anaerobic metabolism products (Yang and Hoffman, 1984;Beaulieu and Saltveit 1997). A high concentration of acetaldehyde and ethanol can inhibit the activity of the ACC oxidase and reduce the ethylene production by fruit (Beaulieu and Saltveit 1997;Pesis 2005;Asoda et al 2009;Thewes et al 2015;Weber et al 2016;Both et al 2017), which helps to explain the low ACC oxidase activity in the fruits stored at 0.4 and 0.25 kPaO 2 . There was no significant difference for titratable acidity and soluble solids ( Fig.…”

“…This technique consists of storing the fruit at oxygen partial pressures above the anaerobic compensation point but lower than in CA, which reduces the metabolism and consequently the consumption of sugars and acids by cell respiration (Weber et al 2013). The storage of apple under extremely low oxygen (ELO) partial pressures, when carried dynamically out, for example in dynamic controlled atmosphere monitored by chlorophyll fluorescence (DCA-CF), maintains higher quality of fruit when they are stored in a 0.4 kPa oxygen partial pressure in comparison to the conventional CA (1.0 kPa O 2 + 1.2 kPa CO 2 ) (Zanella et al 2008;Weber et al 2016). However, it is likely that extremely low partial pressures of oxygen (below 0.5 kPa O 2 ) used in a static atmosphere may have a good effect on apple quality maintenance.…”

A Combination of Melatonin and Ethanol Treatment Improves Postharvest Quality in Bitter Melon Fruit

“…Ethanol is a kind of natural volatile compound with the characteristics of low toxicity and environmental friendliness that has been generally recognized as a safe (GRAS) substance by the Food and Drug Administration (FDA) [ 10 ]. Previous studies have shown that ethanol has the potential for delaying the ripening of “Royal Gala” apples [ 11 ] and retaining high marketability of edible petunia flowers and cherry tomatoes [ 12 , 13 ]. As a well-known preservative, ethanol has played an essential role in horticultural products during the postharvest phase.…”