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Fruit of pepper (Capsicum annuum L.) is hollow by nature, which limits its water reservoir capacity, and as such, small amounts of water loss result in loss of freshness and firmness, which reduce fruit quality, shelf life, and market value. In order to understand the basis for water loss from fruit, 10 pepper accessions with wide variation in water loss rate were used to study physiological and biochemical factors associated with postharvest water loss in ripe pepper fruit during storage. Postharvest water loss rate in ripe pepper fruit stored at 20 °C, and 85% relative humidity, was found to be associated with cell membrane ion leakage, lipoxygenase activity, and total cuticular wax amount. Total cuticular wax amounts were highest in the high-water-loss pepper fruit, and lowest in the low-water-loss fruit. However, total cuticle amount (isolated enzymatically and quantified gravimetrically), total cutin monomer amount, and the amount of individual cutin monomer and wax constituents (determined using gas chromatography mass spectrometry) indicated no direct association with postharvest water loss rates. Fruit fresh weight, pericarp weight, pericarp surface area, pericarp thickness, initial water content, and dry matter were highly associated with each other, but less so with water loss rate. Fruit of accessions displaying high fruit water loss rate matured and ripened earlier than fruit of accessions displaying low-water-loss rate. Cell membrane ion leakage and lipoxygenase activity were higher after storage than immediately after harvest. Pepper fruit total cuticle wax amount, lipoxygenase activity, and cell membrane ion leakage were directly related to postharvest water loss rate in pepper fruit during storage.

The goal of this work was to evaluate the external, internal and sensory traits of ‘Galia’-type melon fruit coated with three polyethylene-based waxes with different solid matter and shellac contents (‘Zivdar’, ‘Tag’ and ‘Tag-A’) or with natural beeswax (‘Beeswax’). After 14 days at 5 °C plus 3 days at 20 °C, the polyethylene-based wax ‘Tag’ was found to maintain both external and internal fruit quality as evaluated by weight loss, firmness, colour development, decay incidence, and soluble solids content. Tag-treated melons also had better sensory quality, as evaluated by organoleptic tests and aroma volatiles. Treatment with the waxes ‘Zivdar’ and ‘Tag-A’, which contain high amounts of shellac in proportion to ‘Tag’ and ‘Beeswax’, significantly increased off-flavour in the melon fruit due to high-internal levels of CO 2 , ethanol, acetaldehyde and ethyl acetate. Untreated fruit, or fruit that were coated with ‘Beeswax’ had the best taste and enhanced ethyl butanoate—(responsible for fruity-pleasant notes), butyl acetate and 2-methyl propyl acetate. Despite the improved organoleptic quality, control and ‘Beeswax’-treated fruit suffered from high-decay incidence and soft texture. Overall good quality and sensory attributes of ‘Galia’-type melon can be achieved by using waxes that contain no, or very low amounts, of shellac. These waxes reduce water loss, improve the general appearance and maintain pleasant, sweet and fruity aroma notes of the fruit even after prolonged storage.

The effectiveness of different postharvest treatments to control different levels of quiescent infections of Alternaria alternata causing Alternaria rot in mango fruits during storage was compared. A combined hot water spray and fruit brushing (hot water brushing - HWB) treatment for 15 - 20 s with 225 μg ml -1 prochloraz was the most effective treatment to control Alternaria rot in fruits with a high relative quiescent infected surface (RQIS) rating of 36 at harvest. Comparable control was obtained with the commercially used treatment of 900 μg ml prochloraz spray. However Alternaria rot in mango fruits with intermediate levels of RQIS rating of 25 was controlled by HWB treatment alone or HWB with chlorine (300 μg ml -1 Troclosene Na). HWB alone was effective enough to control postharvest decay in fruits with a RQIS of 5. Present results have indicated that effectiveness of postharvest HWB and prochloraz applications, are dependent on the quiescent infected area of the fruit by A. alternata at harvest. A RQIS rating, before harvest, has resulted in the use of effective, mild, fungicides as a single postharvest treatment thus avoiding wide use of less friendly synthetic fungicides.

The effectiveness of different postharvest treatments to control different levels of quiescent infections of Alternaria alternata causing Alternaria rot in mango fruits during storage was compared. A combined hot water spray and fruit brushing (hot water brushing-HWB) treatment for 15–20 s with 225 μg ml−1 prochloraz was the most effective treatment to control Alternaria rot in fruit with a high relative quiescent infected surface (RQIS) rating of 36 at harvest. Comparable control was obtained with the commercial treatment of 900 μg ml−1 prochloraz spray. However, Alternaria rot in mango fruit with an intermediate level of RQIS rating of 25 was controlled by HWB treatment alone or HWB with chlorine (300 μg ml−1 Troclosene Na). HWB alone was effective enough to control postharvest decay in fruit with a RQIS of five. Present results have indicated that effectiveness of postharvest HWB and prochloraz applications are dependent on the quiescent infected area of the fruit by A. alternata at harvest. A RQIS rating, before harvest, has resulted in the use of effective, mild, fungicides as a single postharvest treatment thus avoiding wide use of less friendly synthetic fungicides.

A treatment of hot water brushing and prochloraz followed by 2,4-dichlorophenoxyacetic acid (2,4-D) diluted in wax, reduced postharvest diseases by 50–70% and improved fruit quality during prolonged storage. Alternaria alternata, Phomopsis spp. and Lasiodiplodia spp. were the main causal organisms of stem end decay. The best control was obtained by concentrations of 2,4-D ranging from 75 to 175 μg ml−1, which could efficiently control side rots caused by A. alternata and the stem end rot-causing pathogens. The combination of hot water brushing, prochloraz application and 2,4-D treatment reduced the incidence of stem end rot after 4 weeks of storage at 14°C and 7 days of shelf life at 20°C from 86 to 10% in cv. Tommy Atkins and from 63 to 12% in cv. Keith. At 175 μg ml−1 2,4-D did not affect fruit firmness or colour development but ensured high quality and fewer rotten fruits.

A combined hot water spray and fruit brushing (hot water brushing–HWB) treatment for 15–20 s was developed for reducing the incidence of postharvest disease caused by Alternaria alternata and improving mango fruit keeping quality. The efficacy of the hot water treatment was tested over a range of temperatures from 48 to 64°C, in combination with prochloraz treatment and fruit waxing. Hot water brushing of fruits significantly reduced decay (infected area) development by A. alternata. But after storage for 3 weeks at 12°C and another week at 20°C, the reduction of disease incidence by HWB and prochloraz treatment (900 μg ml−1) was more effective than by HWB alone. HWB treatment for 15 s improved colour development and was more effective than the common, commercial 5 min dip treatment at 55°C. The combination of fruit HWB and waxing yielded high quality fruits with less decay development.

Water loss was found to be a nondestructive indicator before visible symptoms of chilling injury (CI) in cold-stored grapefruit (Citrus paradisi Macf.) and lemon (C. limon L. Burm. f.). The water-loss rate increased significantly after removing the fruit from cold storage and holding at 20C. Scanning electron microscopy revealed large cracks around the stomata. Changes in electrical conductivity of the flavedo tissues, total electrolyte leakage, and K+ or Ca2+ leakage were all inadequate predictors of CI, appearing only after CI was evident.

Cultivar ‘Ortanique’ tangor citrus fruit stored for 3 months at temperatures between 5 and 11°C kept their marketable qualities, and even improved in colour, taste and ease of peeling. Storage at 13°C led to fast deterioration and storage at 2°C caused chilling injury. Warming the fruits to 13°C for 7 days every 3 weeks during storage at 2°C prevented chilling injury and eliminated rot development. Waxing the fruits before storage had no effect on quality after storage. Generally, post-harvest changes occurring in ‘Topaz’ were very slight under most conditions examined.

“Abstract. Britex and Zivdar, water-based polyethylene waxes, were applied in commercial and experimental formulations as spray coating, a single dip, or double dips on ‘Murcott’ tangerine (Citrus reticulate Blanco) fruits. Postharvest waxing of ‘Murcott’ tangerine reduced weight loss but affected the sensory characteristics of the fruit. Charges in fruit weight loss and juice composition occurred in the waxed fruits after 4 weeks of storage at 5C plus 1 week of simulated retail handling at 17C. Changes quality. ‘Murcott’ is a hybrid tangerine cultivar that has been grown in Israel for almost 15 years. The fruit is flat (oblate) with a yellowish peel and a firm texture. The flesh is tender, very sweet and juicy, and has a very rich flavor. Harvested fruit, however, especially those that are waxed, develop off-flavors regardless of rootstock origin, maturity at harvest, or storage conditions (Cohen et al., 1985). Newhall and Grierson (1955) emphasized the necessity of wax coating citrus to impart a high gloss to the skin and to prevent water loss and shrinkage, thus prolonging the marketing life of fresh fruit. However, Davis et al. (1967, 1973) showed that waxing various citrus fruit cultivars affects respiration and composition of the internal atmosphere, leading to the development of distinct off-flavors. In studies of physiological changes occurring in citrus fruits during storage, ethanol was found to be the volatile component undergoing the greatest change (Davis and Chace, 1969). Ethanol buildup and off-flavors in juice were found after multiple coatings of either water- or solvent-solub le waxes were applied to oranges. These detrimental effects emphasize the dangers of overtaxing (Davis and Hoffmann, 1973). The aim of this study was to determine whether various wax formulations, either those already in use commercially or those experimentally produced for coating ‘easy-to-peel” fruits, differ in their influence on physiological, chemical, and sensory characteristics of ‘Murcott’ tangerines during storage and simulated retail handling (shelf-life).

The effect of fosetyl-aluminium on the control and spread of brown rot disease Phytophthora citrophthora in post-harvest citrus fruit was studied in laboratory and semi-commercial experiments. Aqueous solutions of fosetyl-aluminium at 5 to 10 g a.i. litre−1 controlled the fungus even when applied 3 days after inoculation at 17°C. No mycelia developed on the peel surface of treated fruit. The fungicide exerted a good prophylactic effect on healthy fruit, protecting them during storage from contact inoculation. Fosetyl-aluminium also showed a fungitoxic effect in vitro and in vivo on other fungi which developed in harvested citrus fruits. Residue levels of phosphoric acid in the treated fruit were higher when the fungicide was incorporated in the wax coating the fruit than when applied in aqueous solution, and levels were lower in the pulp than in the peel. It is concluded that fosetyl-aluminium is a suitable commercial post-harvest treatment for control of brown rot in citrus fruits.

Mature green lemon (Citrus limon Burm.) fruits are degreened commercially with ethylene to enhance yellow color development and improve marketing quality. This treatment often results in the development of a peel disorder called red blotch, a superficial reddish-brown discoloration, which may cover most of the fruit peel. We found that degreening at 30°C, instead of the recommended temperature of 25°, eliminated the disorder. Similarly, a predegreening treatment of dipping the fruit in the antioxidant ethoxyquin (“Stop Scald”) prevented red blotch development. The high temperature and the antioxidant may act on oxidative enzyme systems, which are apparently causative factors of the disorder.