Shelf-life Of Melon Research Articles

Targeted modification of CmACO1 by CRISPR/Cas9 extends the shelf-life of Cucumis melo var. reticulatus melon.

The gaseous plant hormone ethylene is a regulator of fruit shelf-life, one of the essential traits in fruits. Extending fruit shelf-life reduces food loss, thereby expected to contribute to food security. The enzyme 1-aminocyclopropane-1-carboxylic acid oxidase (ACO) is the final step of the ethylene production pathway. Its suppression via antisense technology has been demonstrated to extend the shelf-life of melon, apple, and papaya. Genome editing technology is an innovative technique for plant breeding. Because the genome editing technology would not leave the exogenous genes in the final crop products, the crops via genome editing can be considered non-genetically modified yields; compared to conventional breeding, such as mutation breeding, the breeding term would be expected to be relatively short. These points include the advantage of this technique in utilization for commercial applications. We attempted to extend the shelf-life of the Japanese luxury melon (Cucumis melo var. reticulatus, 'Harukei-3') via modification of the ethylene synthesis pathway with the genome editing technology, CRISPR/Cas9 system. The Melonet-DB (https://melonet-db.dna.affrc.go.jp/ap/top) showed that the melon genome had the five CmACOs and the gene CmACO1 predominantly expressed in harvested fruits. From this information, CmACO1 was expected to be a key gene for shelf-life in melons. Based on this information, the CmACO1 was selected as the target of the CRISPR/Cas9 system and introduced the mutation. The final product of this melon did not have any exogenous genes. The mutation was inherited for at least two generations. In the T2 generation, the fruit phenotypes 14days after harvest were as follows: ethylene production was reduced to one-tenth that of the wild type, pericarp colour remained green, and higher fruit firmness. Early fermentation of the fresh fruit was observed in the wild-type fruit but not in the mutant. These results show that CmACO1 knockout via CRISPR/Cas9 extended the melon's shelf-life. Moreover, our results suggest that genome editing technology would reduce food loss and contribute to food security.

Induction of postharvest resistance in melon using pulsed light as abiotic stressor

The aim of this study was use the pulsed light (PL) as tool to booster the postharvest resistance in melons. Cantaloupe melons at mature stage were submitted to the treatments as follows: control, pulsed light (PL; 9 J cm−2), 1-methylcyclopropene (1-MCP; 600 nL L-1) and 1-MCP + PL (600 nL L-1 + 9 J cm−2). Postharvest resistance measurements according survival analysis developed at 4 °C, included: ethylene production, 1-aminocyclopropane-l-carboxylic acid (ACC) oxidase activity, ACC synthase activity, firmness, pH, soluble solids, titratable acidity, SS/AT ratio, soluble sugars, vitamin C, total polyphenols, phenylalanine ammonia lyase (PAL) activity, colour epicarp, free polyamines (putrescine-Put, spermine-Spe and spermidine-Spd) and total polyamines (TPo). Combined effect of the PL+1-MCP promoted an additional of 12 days in the shelf life of melons. PL limited the ethylene biosynthesis leading to an immediate upregulation of polyamines (Put + Spe + Spd), hence, associated with high amounts of TPo (56%). PL treatment promoted an increase of PAL activity (67%) that synthesized high content of phenolic compounds (55%). The results suggest that PL with a fluence of 9 J cm−2 stimulate the postharvest defense mechanisms in melon, due to the ethylene production limitation, which was influenced by the increased polyamines, maintaining the quality attributes.

Pre-Harvest Application of Plant Biostimulant on the Quality and Shelf-Life of Yellow Melon (Cucumis melo L.)

The purpose this work was to evaluate the influence of pre-harvest application of plant biostimulant on the quality and shelf-life of melon. For this an experiment was established in the “Coopyfrutas”, located in Rio Grande do Norte state/Brazil. The treatments consisted of a combination of factors: melon cultivars (‘Goldex’ and ‘Iracema’) and pre-harvest application of plant biostimulant, Crop Set®, (with and without). At commercial maturity, some fruit of each treatment were sampled and analyzed and the others were stored in a cold chamber at 10±2 ºC and 80±2% relative humidity. The experiment was arranged in a completely randomized split-plot design. The plots consisted of cultivars and Crop Set® application and subplots of different storage time (0, 14, 21, 28, and 35 days after harvest) with eight replications. The characteristics evaluated were length, diameter, internal cavity, external and internal appearance, weight loss, fresh firmness, soluble solids, titratable acidity, pH, SS/TA ratio, and total soluble sugars. Applications of plant biostimulant led to an increase in fruit length and diameter. It reduced fresh firmness and increased the pH of ‘Goldex’ fruit. The total soluble sugars reduced at 35 days of storage in the ‘Iracema’ fruit treated with plant biostimulant.

The Effect of Storage Temperatures on Quality of Minimally Processed Cantaloupe Melon (Cucumis melo L.) with Cassava Starch Based Edible Coating Application

Minimally processed Cantaloupe melon has a short life because it contains high water content which is speeding up the process of spoilage. The objectives of the research were to determine the stearic acid addition on edible coating from cassava starch with low temperature storage to maintain the quality and to extend the minimally processed melon shelf life. This research used a factorial randomized complete design. Edible coating solutions were composed of 3 % cassava starch (w/v), 1 % carbo methyl cellulose (w/v) and 5 % glycerol (v/v). The treatments consisted of two factors, the first factor was the stearic acid addition on edible coating of 4 levels (0%, 0.5%, 1%, and 1.5%) and the second factor was low temperature storage with 2 levels (5°C and 10°C) with three replications. Observed parameters were respiration rate, moisture content, total titratable acidity, total soluble solids, color and weight loss. Results of this research showed that the best treatment of processed Cantaloupe was the temperature storage of 5°C and the 1.5% stearic acid addition for 5 days storage with respiration rate 33.59 mgCO2/kg hour; moisture content 8.48% (d.b.) ; total titratable acidity 38%; total soluble solid content 6.17 obrix; Hue angle 88.79o (yellow); and weight loss 5.85%.

Exposure to minimally processed pear and melon during shelf life could modify the pathogenic potential of Listeria monocytogenes

Survival and virulence of foodborne pathogens can be influenced by environmental factors such as the intrinsic properties of food as well as the extrinsic properties that contribute to food shelf life (e.g., temperature and gas atmosphere). The direct contribution of food matrix characteristics on the survival of L. monocytogenes during fresh-cut fruit shelf life is not very well understood. In addition, the gastrointestinal tract is the primary route of listeriosis infection and penetration of the intestinal epithelial cell barrier is the first step in the infection process. Hence, the pathogenic potential of L. monocytogenes, measured as the capability for the organism to survive a simulated gastrointestinal tract and the proportion of cells able to subsequently adhere to and invade differentiated Caco-2 cells, subjected to fresh-cut pear and melon shelf life, was investigated. Samples were inoculated, stored at 10 °C for 7 days and evaluated after inoculation and again after 2 and 7 days of storage. A decrease in L. monocytogenes’ capacity to survive a simulated gastrointestinal tract was observed with increasing storage time, regardless of the fruit matrix evaluated. Furthermore, L. monocytogenes placed on fresh-cut pear and melon was subjected to an attachment and invasion assay after crossing the simulated gastrointestinal tract. After inoculation, pathogen on fresh-cut pear showed 5-fold more capacity to adhere to Caco-2 cells than pathogen on fresh-cut melon. After 2 days of storage, L. monocytogenes grown on fresh-cut melon showed similar adhesive capacity (1.11%) than cells grown on pear (1.83%), but cells grown on melon had the higher invasive capacity (0.0093%). We can conclude that minimally processed melon could represent a more important hazard than pear under the studied shelf life.

Combining of Bacteriophage and G. asaii Application to Reduce L. monocytogenes on Fresh-Cut Melon under Low Temperature and Packing with Functional Film

Gluconobacter asaii (a bacterial antagonist naturally occurring on apple fruit) and bacteriophage were tested as biocontrol agents of Listeria monocytogenes on fresh-cut honeydew melon pieces during low temperature and packing with functional film made by zeolite mixed pegmatite thickness with 20 m. Gluconobacter asaii and bacteriophage were effective against of L. monocytogenes, but combining the two treatment was even more effective. G. asaii alone treatment reduced density approximately 4 to 5 logs and phage alone reduced populations by one log compared to the L. monocytogenes control. In comparison Listeria control treatment combining treatments reduced populations up to 6 logs by day 7 especially packing with functional film. Also shelf-life of melon with functional film extend 5~6 days compared to none film treatment under low temperature. The results of our study suggest that G. asaii and phage when combined could be very effective in reducing L. monocytogenes contamination of fresh-cut honeydew melon under low temperature and packing with functional film.

멜론(Cucumis melo L.) 수확 후 관리기술 최근 연구 동향

Among Cucubitaceae, melon (Cucumis melo) is one of the most diversified fruits, with various forms, sizes, pulps, and peel colors, In addition, it is a commercially important crop because of its high sweetness, deep flavor, and abundant juice. In the species, there are both climacteric and non-climacteric melons depending on the respiration and ethylene production patterns after harvest. Ethylene is also considered a crucial hormone for determining sex expression, Phytohormones other than ethylene interact and regulate ripening, There are some indices that can be used to evaluate the optimum harvest maturity. The harvest time can be estimated after the pollination time, which is the most commonly used method of determining the harvest maturity of the fruit. Besides the physiological aspects, the biochemical alterations, including those of sweetness, firmness, flavor, color, and rind, contribute to the overall fruit quality. These changes can be categorized based on the ethylene-dependent and ethylene-independent phenomena due to the ethylene-suppressed transgenic melon. After harvest, the fruits are precooled to to reduce the field heat, after which they are sized and packed. The fruits can be treated with hot water ( for 60 min) to prevent the softening of the enzyme activity and microorganisms, and with calcium to maintain their firmness. 1-methylenecyclopropene (1-MCP) treatment also maintains their storability by inhibiting respiration and ethylene production. The shelf life of melon is very short even under cold storage, like other cucurbits, and it is prone to obtaining chilling injury under . In South Korea, low-temperature () storage is known to be the best storage condition for the fruit. For long-time transport, CA storage is a good method of maintaining the quality of the fruit by reducing the respiration and ethylene. For fresh-cut processing, washing with a sanitizing agent and packing with plastic-film processing are needed, and low-temperature storage is necessary. The consumer need and demand for fresh-cut melon are growing, but preserving the quality of fresh-cut melon is more challenging than preserving the quality of the whole fruit.