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Aroma volatiles are important components of the sensory quality of fruit. In recent decades, the long shelf-life character has been introduced into commercial varieties of fruit such as tomatoes or melons through the use, in breeding programmes, of mutants impaired for ethylene perception. Extension of shelf life has resulted in a strong reduction of aroma volatiles production indicating a negative correlation between aroma production and ethylene perception or synthesis.

Physiologists have historically divided ripening into two general classi- fications, climacteric and nonclimacteric, based on the presence or absence of dramatic ripening-related increases in respiration, respectively (Biale and Young, 1981). This concept is fundamental to any discussion of ethylene in postharvest systems. Two reviews of this topic (Biale and Young, 1981; Goldschmidt, 1997) concluded that both categories represent an oversimplification.

Minimally processed vegetables (MPV) are prepared and handled to maintain their fresh nature while providing convenience to the consumer, as ready-to-eat products. Cut operations during the MPV preparation induce activation of several biochemical processes leading, for example, to an increase of ethylene production and tissue browning. Enzymatic browning is the result of the oxidation of phenols that are produced starting by phenylalanine ammonia lyase (PAL). In plants, selenium (Se) is well known for its high potential of protecting biomembranes, eradicating free particles, and delaying senescence (Pezzarossa ., 1999).

A new palladium-promoted material was discovered with significant ethylene adsorption capacity. The material effectively scavenged exogenously administered and/or endogenously produced ethylene by climacteric fruit. Corresponding inhibition of ethylene-induced ripening was observed.

The postharvest shelf-life of arazá fruit is approximately 72 h at 20°C due to exacerbated dehydration, softening, and eventual anthracnose infection (Hernández and Trujillo, 2004). Softening and skin color changes can be closely associated with the pattern of ethylene production (Flores ., 2001; Rogez ., 2004). Here we determine ethylene production in arazá fruits when stored at three different temperatures, and in relation to the onset of respiration rate and several quality traits.

Maturity at harvest influences all aspects of postharvest life and quality of fruit. In climacteric fruits, such as nectarines, ripening is characterized by increasing ethylene production (EP) and loss of firmness (F), but great variability was observed between fruit (Tonutti ., 1996). Recently, it has been shown that the absorption coefficient at 670 nm (a), measured by time-resolved reflectance spectroscopy (TRS) on ‘Spring Bright’ nectarines, is a valuable tool to assess the maturity, i.e. the biological age, of individual fruit without disrupting its structure (Eccher Zerbini ., 2006). The aim of this research was to study EP in relation to both fruit maturity at harvest, as measured by TRS, and to softening at two postharvest ripening temperatures.

‘Raínha Claudia verde’ plums fruits are usually stored at 0–2°C. This cultivar has a small commercial period because of its short postharvest life. In cold chambers fruits became soft very quickly and were not adequate for sale.

The fruit of melting-flesh peach ( (L). Batsch) produces increasing levels of ethylene, and the flesh firmness softens rapidly during the ripening stage. On the other hand, stony hard peaches barely soften on the tree or after harvest, although the fruit changes colour normally, contains highly soluble solids and has good flavour (Haji , 2001). It has been assumed that a low level of ethylene production by stony hard peach is responsible for the inhibition of fruit softening, because exogenous ethylene softens them effectively (Hayama , 2003; Haji , 2003).

Fruit ripening is a complex, genetically programmed process. It has been shown that many ripening processes of climacteric fruit are regulated by ethylene (Alexander and Grierson, 2002). Despite the understanding of ethylene biosynthesis and perception, the mechanism regulating fruit ripening, including factors for the ethylene climacteric, remain obscure. To obtain information on the genetic mechanism which underlies the pleiotropic effects of ethylene, we screened 10,911 tomato cDNA clones for responsiveness to hormone treatment and difference in genetic background using cDNA macroarray technology.

Peach ( (L.) Batsch) fruit are climacteric and an increase in ethylene production is observed during fruit ripening. However, the relationship between ethylene and fruit softening is unclear, because peach fruit softening begins significantly earlier than the observed increase in ethylene production (Tonutti ., 1996). The stony hard peach is an ideal mutant for studying the relationship between fruit softening and ethylene. In this mutant, the ripe fruit produces little ethylene and firm flesh is maintained during ripening, but exogenous ethylene induces a rapid loss of firmness (Haji ., 2003), which accompanied by increases in both endo- PG and exo-PG activities (Hayama ., 2006).