Mechanical fruit removal

Anatomy of the abscission zone at the base of mature fruits has been investigated in apples (10), cherries (11), citrus (12), and olives (13) and has been discussed as related to mechanical fruit removal (2, 14), The histochemistry of the separation layer of mature fruit is very similar to that of leaves of citrus (15) and bean (16,17), The actual separation occurs through one or more processes in the separation zone (a) a weakening of the cementing ability of the middle lamella between cells, and (b) a softening of the entire cells (17), In some plants, the abscission zone is structurally differentiated as a layer of compact cells or as a zone of localized cell division in other species, abscission may occur across a transect of cells which show little or no visible diflFerentiation (18). Thus, major components of the separation process involve the dissolution of middle lamella and lysis of cell walls or entire cells in the separation zone, but this is not necessarily associated with distinctive morphological characteristics (19). 

Matsuo T, Ito S (1977) On mechanisms of removing aastringency in persimmon fruits by carbon dioxide treatment I. Some properties of the two processes in the deastringency. Plant Cell Physiol 18 17-25... 

In consequence, if a sink exists in a leaf (or fruit), 2,4-D molecules will move out of the inner volume element much more rapidly than the outer skin can be penetrated. Under these conditions, 2,4-D will not accumu-late in cuticles as long as sink activity continues and permeability of the outer volume elements is lower than the rates of removal into sinks. In this context, the sink may involve sorption into membrane and storage lipids, metabolization, conjugation, or other mechanisms of removal. 

To remove the essential oil from the peel of citrus fruits, the oil glands, which are located in the flavedo (the outer coloured portion of the peel), are ruptured by mechanical systems. The oil is washed away with a spray of water to produce an oil-in-water emulsion with small peel particles. To prevent absorption of the essential oil by the spongy albedo (the iimer white portion of the peel), this emulsion is passed through a screening device (finisher) of 0.5 to 0.7 mm in diameter, which removes the coarsest particles of the fruit peels [12]. 

Plant gums may be defined as those substances of plant origin which are obtained as exudations from the fruit, trunks or branches of trees spontaneously or after mechanical injury of the plant by incision of the bark or by removal of a branch, or after invasion by bacteria or fungi. 

An active abscission research program for citrus has been underway for a number of years in Florida by the Florida State Citrus Commission in collaboration with a number of chemical companies. This program was initiated originally because of a shortage of labor for handpicking citrus. Chemicals to speed up the removal of fruit by mechanical harvesters and to increase... 

Expression A mechanical method using compression and pressure for removing essential oils from the skins of citrus fruits, e.g. lemon, orange, bergamot. 

Coconut Oil (Unhydrogenated) occurs as a viscous, white to light yellow-tan liquid. It is obtained from the kernel of the fruit of the coconut palm Cocos nucifera (Fam. Palmae). The crude oil obtained by mechanically pressing dried coconut meat (copra) is refined, bleached, and deodorized to substantially remove free fatty acids, phospholipids, color, odor and flavor components, and other non-oil materials. Compared with many natural fats, Coconut Oil (Unhydrogenated) has an abrupt melting range, changing from a rather firm, plastic solid at about 21° or below to a liquid at about 21°. 

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