Ripening retardation

Previous publications reported that ethanol treatment retarded ripening of several fruits, including whole tomatoes and tomato slices (Saltveit and Mencarelli 1988). Also, ethanol can slow down tomato ripening by inhibiting synthesis and action of ethylene,... 

The objective of irradiation of food with y-rays is elimination of parasitizing insects, fungi, and bacteria to prevent premature spoiling of the food and the outbreak of diseases. In addition, retardation of aging and ripening of fruits and vegetables can be achieved. In the Federal Republic of Germany, irradiation of food with the exception of spices is not permissible. 

The tolerance limitation of fruit for irradiation establishes the maximum acceptable dose. If this dose controls decay organisms, the use of irradiation for a particular fruit may appear promising. Response to irradiation may be influenced by fruit maturity, variety, pre- and postharvest temperatures, handling, and extent of fungus growth. Climacteric fruits irradiated prior to the normal rapid increase in respiration usually show an immediate increase in respiration and the production of ethylene. These fruits are frequently retarded in ripening. 

On the other hand, IPA consistently inhibits ethylene production at all stages of ripening throughout the climacteric and postclimacteric periods. No greater retardation is achieved by addition of GA and IAA to IPA at this stage. 

Feedback Relationship Between Ethylene and Other Plant Hormones If ethylene production in ripening fruit is an index of aging and senescence, then its suppression should result in retardation, or antagonism to ripening, aging, and senescence. 

Emulsifiers or stabilizers in various goods texturizers in various goods components of protective coatings applied to a re-stiicted number of fruits to retard ripening... 

If Ostwald ripening is retarded by using a costabilizer, predominant droplet nucleation can be achieved. This is the basis of miniemulsion polymerization. One of the first comprehesive studies of miniemulsion polymerization was done on styrene by Choi et al. [53]. 

Wang and Schork [73] used PS, PMMA and PVAc as the costabilizers in miniemulsion polymerizations of VAc with PVOH as the surfactant. They found that, while PMMA and PS were effective kinetic costabihzers (at 2-4%wt on total monomer) for this system, PVAc was not. While the polymeric costabilizers did not give true miniemulsions, Ostwald ripening was retarded long enough for predominant droplet nucleation to take place. 

Mouran et al. [105] polymerized miniemulsions of methyl methacrylate with sodium lauryl sulfate as the surfactant and dodecyl mercaptan (DDM) as the costabilizer. The emulsions were of a droplet size range common to miniemulsions and exhibited long-term stability (of greater than three months). Results indicate that DDM retards Ostwald ripening and allows the production of stable miniemulsions. When these emulsions were initiated, particle formation occurred predominantly via monomer droplet nucleation. The rate of polymerization, monomer droplet size, polymer particle size, molecular weight of the polymer, and the effect of initiator concentration on the number of particles all varied systematically in ways that indicated predominant droplet nucleation. 

The use of ozone in control of surface mold on packages and walls in apple storage and maintenance of a pleasant odor has been reported by a number of investigators 12, 16, 28, 31), Ozone has also been used to retard ripening of fruits. Ethylene gas liberated by fruit stimulates the ripening. The gas is readily oxidized by ozone 2,14). The Sterilamp tube has been used to provide a controlled amoimt of ozone to oxidize this gas and other odors as well as to destroy microorganisms in apple storage rooms. 

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