Ethylene fruit with

Alumot E, Chalutz E. 1972. Fumigation of citrus fruit with ethylene dibromide. Desorption of residues and ethylene evolution. Pestic Sci 3 539-544. 

Degreening of peel has been related to chlorophyllase activity. Barmore (14) demonstrated that chlorophyllase activity in peel increased following treatment of fruit with ethylene. 

Cohen (21) has suggested the use of an "intermittent" exposure to ethylene and heat for degreening. The method consists of treating fruit with 10 ppm of ethylene at 25°C for 12 hr intervals. During the 12 hr interruption, the ethylene dropped to 0 to 1 ppm and the temperature dropped 1 to 2°C. 

Several postharvest treatments to citrus fruits have been tested in an effort to improve the quality of the extracted juice. Bruemmer and Roe subjected citrus fruits to anaerobic conditions for periods of 20 to 32 hours at 32.2 to 43°C (228, 229). This treatment reduced the titratable acidity and increased the Brix-acid ratio by about 10%. The decrease in acidity was accompanied, however, by a 20-fold increase in ethanol (229). Since the soluble solids-acid ratio is a major criterion of citrus juice quality, this procedure, if perfected, could allow earlier harvesting of fruit and a more consistent supply of fruit during the processing season. Bitterness of products from navel oranges, lemons, and grapefruit is related to limonin content. A 3-hour treatment of fruit with 20 ul ethylene/1 of air lowered the limonin content, reduced bitterness, and the juice was judged more palatable than juice from untreated fruit (230). 

Pre-treatment of apples with high CO2 can induce respiration and ethylene production at 20 °C storage, in addition to induction of other volatiles. These CO2" treated apples were rated by panelists as better flavoured than control fruit, with the 24-h-treated fruit being the most acceptable after 2 weeks at 20 °C (Pesis et al. 1994). 

Halinska A, Frenkel C (1991) Acetaldehyde stimulation of net gluconeogenic carbon movement from applied malic acid in tomato fruit pericarp tissue. Plant Physiol 95 954-960 Hirai J, Hirata N, Horiuchi S (1968) Effect of oleification on hastening the maturity of the fig fruit. VI. Respiration and changes in concentrations of metabolic substances in the treated fruits with products in oxidative process of fatty acid such as acetaldehyde or ethylene. J Jpn Soc Hortic Sci 37 20-29... 

Ethylene is a gas with a sweet odor. It is obtained from the refining of petroleum and is an important raw material in the chemical industry. For example, when ethylene molecules are linked they make polyethylene (see Section 25.1), which is commonly used to make soda bottles and milk jugs. Plants also produce small amounts of ethylene. Fruit suppliers have found that exposure of fruit to ethylene speeds ripening. 

Hussain, M., Bensaid, S., Geobaldo, R, Saracco, G., and Russo, N. Photocatalytic Degradation of Ethylene Emitted by Fruits with Ti02 Nanoparticles. Ind. Eng. Chem. Res., 50, 2536-2543... 

Substantial quantities of UPVC are also used for blow moulded containers for such diverse materials as consumable liquids such as fruit squashes, liquids for household use such as detergents and disinfectants, cosmetics and toiletries, and pharmaceuticals. For most of these applications UPVC is in competition with at least one other polymer, particularly poly(ethylene) terephthalate (Chapter 25), polyethylene (Chapter 10), polypropylene (Chapter 11) and, to a small extent, the nitrile resins (Chapter 15). The net result is that in recent years there has been some replacement of PPVC in these areas, in part because of problems of waste disposal. 

Ethylene is a colorless, flammable gas with a boiling point of-104 °C. More than 22 billion kilograms of ethylene are produced annually in the United States, making it one of the top five industrial chemicals. The manufacture of plastics (polyethylene is the most common example) consumes 75% of this output, and much of the rest is used to make antifreeze. Because ethylene stimulates the breakdown of cell walls. It Is used commercially to hasten the ripening of fruit, particularly bananas. 

Fig. 1. Promotion of ethylene synthesis by MG pericarp discs following treatment with water or varying concentrations (uronic acid equivalents) of B fruit water soluble fraction. Bars indicate SEs for the means of measurements of sets of 8 discs/teatment fr wt, Fresh weight.

The synthesis of endo-PG occurs in the ripening stage after an increase of ethylene production [21] and its appearance has been correlated with an increase in soluble pectin and softening [22]. Exo-PG is suggested to participate in the initiation of climacteric ethylene production [23]. Strawberry fruit has been accepted to be a non-climacteric fruit and ethylene... 

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