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Introduction: Owing to increase demand for safer and health promoting vegetable oils, a number of potential sources are being explored by researchers. Materials and Methods: In this study, oil was extracted using Soxhlet from Sokoto locally grown Cucumis melo L (honeydew melon). Physical and chemical properties (colour, moisture, pH, specific gravity, refractive index, acid value, iodine value, saponification value and peroxide value) of the oil were determined using standard analytical methods by Association of Official Analytical Chemists (AOAC). Results: The results showed the percentage yield of the oil to be 27.46%. Physically, the oil was yellowish in colour, liquid at room temperature, with pH of 6.2 (0.01), specific gravity of 0.89 (0.32), and refractive index of 3.62 (1.0). The saponification, acid, iodine and peroxide values of the oil were 45.81 (5.19), 9.16 (0.21), 64.80 (4.31) and 10.50 (1.50) respectively. Conclusion: The results suggest that the oil has a potential for use as vegetable oil, in industries and, subject to further evaluation of the contents, health promoting purposes.

Yield and quality in cantaloupe, or honeydew melon (both Cucumis melo L.) are important parameters for cultivar selection, potentially impacting grower profitability. Information on melon cultivar ...

In the current work, a new honeydew melon peels activated carbon (HDP-AC) with sulfuric acid (ACS) and phosphoric acid (ACP) was introduced as adsorbent for removing Cr3+ and Zn2+ from wastewater. ...

An oscillating magnetic field (OMF) was used to extend the supercooled state in honeydew melon samples. The internal temperature of the samples under OMF treatment was kept at -5.5°C during a 21-day storage period without freezing. To inhibit ice crystal nucleation, the OMF treatment was controlled using a repeated sequence of on/off cycles with durations of 120/420 s. Quality factors of the supercooled samples were measured and compared with fresh, refrigerated, and frozen samples. Factors such as microbiological analysis, drip loss, pH, titratable acidity, and soluble solids contents indicated that the overall quality of the supercooled samples after 21 days was not significantly different (p > 0.05) from that of fresh samples. Although a few cells in the supercooled samples had undulated walls compared to fresh samples under microscopic analysis, the cells were closely bonded to each other, and distorted cells were not found. Keywords: Fresh-cut fruits, Honeydew melon, Oscillating magnetic fields, Quality assessment, Subzero preservation.

The sensory and functional quality attributes of muskmelons (Cucumis melo L.), such as flavor, sweetness, color, and texture, determine consumer preferences. Genetic makeup primarily regulates these traits, but environmental factors such as soil type, irrigation, and temperature affects yields and quality. Here, we investigated variation in quality traits of diverse melon cultigens (advanced breeding lines or cultigen) grown in multiple locations (California, Texas, Georgia, Arizona, and North Carolina) across the United States. Mesocarp sugar and carotenoid concentrations varied significantly as a function of production location and cultigen. Multivariate analyses revealed significant cultigen, location, and interactive effects on fruit quality. The highest sugar content was found in a honeydew melon cultigen (HD-150; 83.1 ± 2.36 mg/g) grown in Georgia and the Western Shipper type cantaloupe (F-39; 70.8 ± 2.85 mg/g) grown in North Carolina compared to the other cultigens. The Tuscan type (Da Vinci) grown in Texas and Georgia had the highest β-carotene concentrations (29.1 ± 3.37 and 33.6 ± 1.73 µg/g, respectively) compared to the other cultigens. These observations, showing that cultivar and location significantly influenced melon phytochemical composition, will help melon breeding programs improve the sensory and functional qualities of melons and identify suitable cultivars for specific environments to maximize fruit quality.

A simple, rapid and reproducible residue analytical method for imazalil in fruits and vegetables has been developed. The method involved the use of an ion-exchange cartridge for sample clean up followed by high performance liquid chromatography with ultraviolet detector. Acetic ether was used for extraction. Bond Elut PRS and Bond Elut C18 were used for purification. The chromatography column used Inertsil ODS-3 and the mobile phase was created by acetonitrile-10 mM KH2PO3 solution (pH 2.5), in the ratio of 35:65. The detection limit is 0.01 ppm. Rape, cabbage, honeydew melon, cumquat, mango and corn were each spiked with 0.05-3.0 ppm imazalil to be compared with the recovery study. The yield was 88.7-97.9% for rape, 72.5-87.4% for cabbage, 81.4-90.5% for honeydew melon, 81.9-87.2% for cumquat, 75.0-85.3% for mango, and 86.8-99.0% for corn. When the method was applied in analyzing commercial fruits and vegetables, no imazalil residue was detected in 20 selected samples.

This study investigated the antimicrobial activities of organic acid vapors against a phytopathogen (Acidovorax citrulli) and foodborne pathogens (Salmonella enterica, Escherichia coli O157:H7, and Listeria monocytogenes) on the surface of Cucurbitaceae seeds. Germination percentages of cucumber, honeydew melon and watermelon seeds treated with acetic and propionic acid vapors (100 mg/L) at 50 °C and 43% or 85% relative humidity (RH) for up to 2 h did not significantly (P > 0.05) decrease. Treatment with formic acid significantly (P ≤ 0.05) decreased the germination percentage. The antimicrobial activities of acetic and propionic acid vapors (100 mg/L; 50 °C; 43% or 85% RH) were determined. A. citrulli was inactivated within 1 h on cucumber and watermelon seeds, regardless of type of organic acid or RH. The phytopathogen was reduced to levels below the detection limit (−0.5 log CFU/g) for enrichment on honeydew melon seeds treated with acetic acid vapor. S. enterica and L. monocytogenes were inactivated within 2 h at 85% RH on honeydew melon and watermelon seeds treated with acetic acid and propionic acid vapors. E. coli O157: H7 was inactivated by treatment with acetic acid vapor at 85% RH. This study provides useful information for developing a method to decontaminate Curcurbitaceae seeds using organic acid vapors as lethal agents.

Honeydew melon (Cucumis melo L.) is an oval-shaped delicious fruit of one cultivar group of the muskmelon with immense nutritional importance and is extensively consumed by many tropical countries. The effect of various organic solvents on the recovery of phytochemicals from honeydew melon plant fruits and seeds was assessed. Further, High-Performance Liquid Chromatography (HPLC) was used to examine and assess the contents of phenolic acid (gallic acid) and flavonoid (rutin) compounds. The use of gas chromatography–mass spectrometry (GC-MS) analysis explained the presence of volatile phytocompounds in the extracts. The use of organic solvents had a substantial impact on the total dry weight and extract yield. In general, the solvent-extracted constituents remained in the order of methanol>chloroform>distilled water for both honeydew melon seeds and whole fruit. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) was used to assess the cytotoxicity effect against PC3, HCT116, HeLa, and Jurkat cell lines. The chloroform extract exhibited a good cytotoxic activity against all cell lines as compared to other solvent extracts. HPLC analysis revealed the occurrence of gallic acid content of 0.102±0.23 mg/10 mg of dry whole fruit extract, while 10 mg of dry seed extract contained only 0.022±0.12 mg of gallic acid content. Likewise, rutin content was observed to be 0.224±0.31 mg and 0.1916±0.82 mg/10 mg of dry whole fruit and seed extract, respectively. Further, GC-MS analysis revealed the presence of a total of 37 compounds in chloroform extract of whole fruit, while only 14 compounds were found in seed extract. Nevertheless, more examinations are needed to identify and characterize other metabolites from honeydew melon and evaluate their pharmacological importance.

The efficacy of plant-based antimicrobials against Salmonella Newport and Listeria monocytogenes on melon rinds was evaluated. Four cantaloupe and 3 honeydew melon varieties grown in Georgia, Arizona, Texas, North Carolina, Indiana and California were tested. Melon rinds (10 g pieces) were inoculated with 5–6 log CFU/10 g rind of S. Newport or L. monocytogenes. Samples were then immersed in 5 % olive extract or 0.5 % oregano oil antimicrobial solution and gently agitated for 2 min. Samples were stored at 4 °C and surviving populations of both bacteria were enumerated at days 0 and 3. Plant-based antimicrobials reduced S. Newport and L. monocytogenes population on all rind samples, regardless of the melon types, varieties or growing locations. Compared to the control, antimicrobial treatments caused up to 3.6 and 4.0 log reductions in populations of Salmonella and L. monocytogenes, respectively. In most cases, plant-based antimicrobial treatments reduced pathogen populations to below the detection limit (1 log CFU/g) at day 3. In general, oregano oil had better antimicrobial activity than olive extract and the antimicrobial treatments were more effective on Salmonella than on L. monocytogenes. The plant-based antimicrobial treatments exhibited better microbial reductions on honeydews than on cantaloupes. These antimicrobials could potentially be used as sanitizers for decontaminating melons.

An experiment was conducted to determine the possibility of using organic materials for the honeydew melon seedling production. Honeydew melon was grown in nine media with different rates of spent ...

To examine possible genetic connectivity between crop viruses found in Southeast Asia and Australia, Papaya ringspot virus biotype W (PRSV-W) isolates from cucurbits growing in East Timor and northern Australia were studied. East Timorese samples from cucumber (Cucumis sativus) or pumpkin (Cucurbita moschata and C. maxima) were sent to Australia on FTA cards. These samples and others of pumpkin, rockmelon, honeydew melon (Cucumis melo), or watermelon (Citrullus lanatus) growing in one location each in northwest, north, or northeast Australia were subjected to high throughput sequencing (HTS). When the 17 complete PRSV genomic sequences obtained by HTS were compared with 32 others from GenBank, the five from East Timor were in a different major phylogroup from the 12 Australian sequences. Moreover, the East Timorese and Australian sequences each formed their own minor phylogroups named VI and I, respectively. A Taiwanese sequence was closest to the East Timorese (89.6% nt dentity), and Mexican and Brazilian sequences were the closest to the Australian (92.3% nt identity). When coat protein gene (CP) sequences from the 17 new genomic sequences were compared with 126 others from GenBank, three Australian isolates sequenced more than 20 years ago grouped with the new Australian sequences, while the closest sequence to the East Timorese was from Thailand (93.1% nt identity). Recombination analysis revealed 13 recombination events among the 49 complete genomes. Two isolates from East Timor (TM50, TM32) and eight from GenBank were recombinants, but all 12 Australian isolates were non-recombinants. No evidence of genome connectivity between Australian and Southeast Asian PRSV populations was obtained. The strand-specific RNA library approach used optimized data collection for virus genome assembly. When an Australian PRSV isolate was inoculated to plants of zucchini (Cucurbita pepo), watermelon, rockmelon, and honeydew melon, they all developed systemic foliage symptoms characteristic of PRSV-W, but symptom severity varied among melon cultivars.

Cantaloupes and honeydew melons inoculated with 10⁷ CFU/ml Salmonella bacteria were treated with 1.5% of hydrogen peroxide (H₂O₂) at 20°C and minimally treated at 70°C for 3 min before storage at 5, 10, and 20°C. Salmonella bacteria recovered from the cantaloupe and honeydew melon rind surfaces averaged 4.5 and 3.9 log CFU/cm², respectively, before antimicrobial treatments. Fresh‐cut pieces prepared at each day of storage were immediately placed inside the refrigerator (5°C) while some pieces were left at room temperature (20°C) for 30 and 60 min before refrigeration. After minimal thermal hydrogen peroxide treatments, injured Salmonella on whole cantaloupes was significantly (p > 0.05) different than honeydew melons. Cold storage of treated melons at 5°C led to significant (p > 0.05) reduction of the injured bacteria and below detection in fresh‐cut pieces even after enrichment process suggesting that minimal thermal antimicrobial processing will reduce transfer of bacteria to fresh‐cut pieces during fresh‐cut preparation. PRACTICAL APPLICATIONS: The results of this study indicate that minimal thermal treatment with 1.5% of hydrogen peroxide at 70°C for 3 min and immediate cold storage of treated whole melons designated for fresh‐cut preparation will reduce transfer of microbial populations from melons rind surfaces to fresh‐cut pieces during fresh‐cut preparation.

Phytophthora capsici was first described by Leon H. Leonian at the New Mexico Agricultural Research station in Las Cruces in 1922 (65). In his report, he described a novel species of Phytophthora that caused considerable damage to chili pepper plants in the fall of 1918. A year later, the disease reappeared at the same site and also affected surrounding farms. During the late 1930s and early 1940s, recurrent problems with P. capsici in the Arkansas River Valley of Colorado were described on several vegetable hosts (51– 55,103). The first reported occurrence of P. capsici on a cucurbit crop occurred in 1937, when a 3.2-ha field of cucumbers became diseased resulting in 100% of the fruit rotting (51). By 1940, P. capsici had also been described on eggplant, honeydew melon fruit, summer squash, and tomato fruit (52,103). The disease on tomatoes was reportedly so severe that the viability of the processing tomato industry in the region was threatened. These early reports mirror the situation with P. capsici today on many modern vegetable production farms, especially those in the eastern United States (4,72,84,94). Our research was initiated in 1997, when crop losses caused by P. capsici threatened to bankrupt a number of vegetable producers in Michigan. Growers wanted to know why crop rotation and the use of fungicides in well-drained fields had not provided adequate protection against full-scale epidemics. At that time, there were fundamental gaps in our understanding of P. capsici’s epidemiology in Michigan, and it was difficult to answer these questions with any degree of certainty. We did not recognize the extent to which sexual recombination and genetic diversity could influence management options and success. In particular, the fungicide mefenoxam was being applied by some growers, and the sensitivity of natural populations of P. capsici in Michigan to mefenoxam was unknown at that time. Here we review recent advances in our understanding of P. capsici’s biology, in particular the role of sexual reproduction, and provide an overview of some of the management challenges presented by this information.

Bright yellow, interveinal chlorosis was observed for the first time on leaves of the older and mid-growth of cucurbit plants in southern Arizona and Sonora (Mexico) during September and October of 2006. Some cultivars exhibited substantial yield losses of 30 to 80%. In Arizona, symptoms were in Cucumis melo (muskmelon and honeydew melon) fields in the Yuma Valley and Hyder. In Sonora, honeydew and muskmelon, Cucurbita pepo (acorn, spaghetti, and summer [yellow and zucchini] squash), and Citrullus lanatus (watermelon) were symptomatic in Hermosillo, whereas, in Caborca, honeydew and cantaloupe developed similar symptoms. Interveinal chlorosis was observed in 60 to 100% of the plants in each field. Crops planted mid-to-late season were 100% infected, whereas, the early-season fields experienced approximately 60 to 80% incidence. All symptomatic fields in the Sonoran Desert and vicinity were infested by the whitefly Bemisia tabaci (Genn.), which was identified as the ‘B biotype’ on the basis of mitochondria COI sequence analysis (data not shown). Whitefly population levels were variable and ranged from 5 to 200 per plant. Total RNA was isolated from leaf samples collected from symptomatic plants using Tri Reagent (Molecular Research Center, Cincinnati, OH). Purified RNA was used in reverse transcriptase-PCR with primers specific to the Cucurbit yellow stunting disorder virus (CYSDV) coat protein (CP) gene (RNA2-deoxyribonucleotide coordinates 4927-4950 and 5657-5679) for the suspected whitefly-transmitted bipartite CYSDV (4). PCR yielded the CYSDV CP fragment, at 753 bp (GenBank Accession Nos. EF21058 and EF21059), which was cloned into pGEM T-Easy and sequenced in both directions using universal primers. The CYSDV CP nucleotide sequences (n = 16) obtained from acorn squash, honeydew melon, muskmelon, yellow squash, and watermelon had 99 to 100% identity. The Arizona (AZ) and Sonora (SON) CYSDV CP sequences shared 99 to 100% identity with previously described CYSDV isolates from the Eastern Hemisphere (GenBank Accession Nos. DQ903105 and DQ903108) and also with two isolates of CYSDV collected during 2004 from Zacapa Valley, Guatemala (GenBank Accession Nos. EF21060 and EF21061) (J. K. Brown, unpublished data). CYSDV is a member of the genus Crinivirus, family Closteroviridae. CYSDV was first identified in cucumber and melon crops in the Middle East approximately 15 years ago and 10 years ago in Spain (1). Most recently, this virus was introduced into Texas (2), Guatemala (J. K. Brown, unpublished data), and Arizona and California (3). CYSDV has therefore emerged as an important and potentially worldwide threat to the production of cultivated cucurbits (3). The threat appears to be significant in light of the introduction or establishment of the exotic B. tabaci biotypes B and Q vectors, which also originated in the Middle Eastern-North African-Mediterranean region. To our knowledge, this is the first report of CYSDV infecting field-grown C. pepo (four types) and watermelon, reported previously only as experimental laboratory hosts, and of CYSDV in two types of melon (C. melo) in Mexico. References: (1) A. Celix et al. Phytopathology 86:1370, 1996. (2) J. Kao et al. Plant Dis. 84:101, 2000. (3) Y.-W. Kuo et al. Plant Dis. 91:330, 2007. (4) L. Rubio et al. J. Gen. Virol. 82:929, 2001.

Hagen, C., Rojas, M. R., Sudarshana, M. R., Xoconostle-Cazares, B., Natwick, E. T., Turini, T. A., and Gilbertson, R. L. 2008. Biology and molecular characterization of Cucurbit leaf crumple virus, an emergent cucurbit-infecting begomovirus in the Imperial Valley of California. Plant Dis. 92:781-793. Cucurbit leaf crumple virus (CuLCrV) is an emergent and potentially economically important bipartite begomovirus first identified in volunteer watermelon plants in the Imperial Valley of southern California in 1998. Field surveys indicated that CuLCrV has become established in the Imperial Valley; and field plot studies revealed that CuLCrV primarily infects cucurbits, including cantaloupe, squash, and watermelon. Full-length DNA-A and DNA-B clones of an Imperial Valley isolate of CuLCrV were obtained by polymerase chain reaction (PCR) with overlapping primers. These clones were infectious in various cucurbits and common bean (cv. Topcrop); symptoms included stunted growth and leaf crumple, curl, and chlorosis. CuLCrV was not saptransmissible, and immunolocalization and DNA in situ hybridization studies revealed that it is phloem-limited. A CuLCrV agroinoculation system was generated, and host range studies revealed differential susceptibility in cucurbits, with squash, watermelon, cantaloupe, and honeydew melon being most to least susceptible, respectively. Germplasm screening studies identified a number of resistant cantaloupe and honeydew melon cultivars. The genome organization of this CuLCrV isolate (CuLCrV-CA) is similar to other bipartite begomoviruses, and phylogenetic analysis placed CuLCrV in the Squash leaf curl virus (SLCV) cluster of New World bipartite begomoviruses. A CuLCrV-specific PCR test was developed which allows for differentiation from other begomoviruses, including SLCV.

Cantaloupes, honeydew melons and watermelons inoculated with Salmonella cocktail at 4.5 log10 CFU/cm2, 3.810 log CFU/cm2 and 3.2 log10 CFU/cm2, respectively were sanitized with 200 ppm chlorine before rinds removal, cutting and juice preparation. Efficacy of 200 ppm chlorine in reducing transfer of Salmonella, aerobic mesophilic bacteria, yeast and mold, and Pseudomonas from the melon surfaces to freshly prepared fruit juice was investigated including the effect of waiting period before refrigeration of the juices. The melon juice filtrates were refrigerated immediately or stored at room temperature (~22oC) for 3 and 5 h before refrigeration. Average Salmonella bacteria recovered in fresh melon juice prepared from unwashed whole cantaloupes, watermelon and honeydew melons was 1.4 log10 CFU/ml, 0.5 log10 CFU/ml and 0.4 log10 CFU/ml, respectively. Juices from unwashed inoculated melons had the highest bacterial populations and storage at an abusive temperature of 10oC led to proliferation. Holding these juices at room temperature for 5 h before refrigeration allowed Salmonella bacteria to increase by 0.5-0.8 log in cantaloupe juice and 0.3-0.5 log in watermelon and honeydew juices. No Salmonella bacteria was determined in fresh juices prepared from melons washed with chlorinated water. The results of this study showed that washing melons with 200 ppm chlorine before juice preparation and immediately refrigerating the juice will minimize the chances of Salmonella proliferation.

The objective of this study was to evaluate effects of spent mushroom substrate (SMS) and chicken manure compost (ChMC) on growth, yield, and fruit quality of honeydew melon and to determine the most suitable rate of SMS for honeydew melon production. Honeydew melon seedlings grown in four different rates of SMS were planted in the net house with two different organic material rates (M1, M2). The experiment was arranged in a split-plot design. The results showed that increasing of organic materials in the net house increased growth, yield, and quality of honeydew melon, due to enhancing of pH, organic matter (OM,) and the nutrient concentrations in the soil. However, growing media with 40 % SMS + 60 % ChMC in the nursery period and the rate of 10 tons SMS + 10 tons ChMC ha−1 in the net house period gave the best yield and fruit quality of honeydew melon.

Effects of chitosan, calcium chloride, and their combination on preventing quality and safety deterioration of postharvest fresh-cut honeydew melon at 7 °C were investigated. Treatments of all these three delayed weight loss, improved firmness, delayed colour changes and moderately inhibited microbial growth. Interestingly, combined treatment of chitosan and calcium chloride was the most effective, leading to 40% less weight loss, 45% (3.70 N) increase in firmness, less overall colour difference, and more than 0.5 log CFU/g inhibition on mesophilic and psychrotropic growths on day 13 of storage as compared to control group. In addition, these treatments also inhibited degradation of pectin chains. Nanostructural analysis of fruit pectin via atomic force microscopy (AFM) indicated that firmness was closely related to the nanostructure of sodium carbonate-soluble pectin (SSP). Short and narrow SSP chains were observed more in samples with less firmness. We conclude that edible coating of chitosan combined with calcium chloride treatment synergistically extends the shelf-life of fresh-cut honeydew melon by maintaining the integrity of SSP via interactions between SSP and calcium ions or protonated chitosan groups.

This experiment was conducted to investigate the possibility of mixing spent mushroom substrate (SMS) with manure composts for honeydew melon (Cucumis melo L. inodorus) seedling production in organic agriculture. The treatments evaluated were 100 % SMS, mixtures of SMS, and chicken manure compost, mixtures of SMS and cattle manure compost in different ratios: 80, 60, 40, and 20 %. The experiment was arranged in a randomized complete block design with three replications under greenhouse conditions. Some physical and chemical characteristics of growing media were determined. Germination rate, morphological growth, survival rate, and nutrient uptake of seedlings were also measured. The results indicated that the addition of manure composts to SMS-based growing media produced a decrease in pH values, air capacity, an increase in electrical conductivity, total water holding capacity, and a difference in nutrient concentrations. Eighty percent SMS can be used in mixtures with manure composts for honeydew melon seedling production. However, SMS at the rate of 40 % gave the most suitable condition for honeydew melon seedling performance.

BACKGROUND Soilborne disease management remains a great challenge in melon production with the phaseout of soil fumigant methyl bromide. Grafting has been shown to be an effective approach to control soilborne diseases. However, previous research has yielded mixed results regarding the impacts of rootstock on fruit quality. Very few studies have assessed melon quality attributes using both sensory evaluation and instrumental methods. RESULTS Galia melon ‘Arava’ (Cucumis melo L. var. reticulatus Ser.) and honeydew melon ‘Honey Yellow’ (C. melo L. var. inodorus Naud.) were grafted onto commercial hybrid squash (Cucurbita maxima Duchesne × Cucurbita moschata Duchesne) rootstocks and root-knot nematode-resistant Cucumis metulifer E. Mey. ex Naud. rootstock. The grafting combinations were evaluated under different production conditions. Grafting with hybrid squash rootstocks resulted in reduced soluble solids content (SSC) and decreased sensory ratings of ‘Arava’ fruit. By contrast with grafted ‘Arava’, grafted ‘Honey Yellow’ did not exhibit significant differences in sensory properties and instrumental measurements regardless of production conditions and rootstock selection. CONCLUSION The effects of grafting on fruit quality attributes differed between the two distinctive types of melon scion used. Potential negative impacts of rootstocks on melon fruit quality need to be considered in the selection and use of disease-resistant rootstocks. © 2014 Society of Chemical Industry

Interest in specialty melons (Cucumis melo) with distinctive fruit characteristics has grown in the United States in recent years. However, disease management remains a major challenge in specialty melon production. In this study, grafting experiments were conducted to determine the effectiveness of using Cucumis metulifer, a species known for its genetic resistance to root-knot nematodes (RKNs; Meloidogyne spp.), as a potential rootstock for managing RKNs in susceptible specialty melon cultivars. In the greenhouse experiment, honeydew melon ‘Honey Yellow’ was grafted onto C. metulifer and inoculated with M. incognita race 1. The grafted plants exhibited significantly lower gall and egg mass indices and fewer eggs compared with non- and self-grafted ‘Honey Yellow’. Cucumis metulifer was further tested as a rootstock in conventional and organic field trials using honeydew melon ‘Honey Yellow’ and galia melon ‘Arava’ as scions. ‘Honey Yellow’ and ‘Arava’ grafted onto C. metulifer exhibited significantly lower galling and reduced RKN population densities in the organic field; however, total and marketable fruit yields were not significantly different from non- and self-grafted plants. Although the improvement of RKN resistance did not translate into yield enhancements, incorporating grafted specialty melons with C. metulifer rootstock into double-cropping systems with RKN-susceptible vegetables may benefit the overall crop production by reducing RKN population densities in the soil. At the conventional field site, which was not infested with RKNs, ‘Honey Yellow’ grafted onto C. metulifer rootstock had a significantly lower total fruit yield than non-grafted ‘Honey Yellow’ plants; however, fruit yields were similar for ‘Arava’ grafted onto C. metulifer rootstock and non-grafted ‘Arava’ plants. Although no significant impacts on the fruit quality attributes of ‘Honey Yellow’ were observed, grafting onto C. metulifer decreased the flesh firmness of ‘Arava’ in both field trials and resulted in a reduction in total soluble solids content under conventional production. In summary, grafting RKN-susceptible melons onto C. metulifer rootstock offers promise for growing these specialty melons; however, more studies are needed to elucidate the scion–rootstock interaction effect on fruit yield and quality.

Interest in producing specialty melons (Cucumis melo) is increasing in Florida, but information on yield performance, fruit quality, and disease resistance of specialty melon cultivars grown in Florida conditions is limited. In this study conducted at Citra, FL, during the 2011 Spring season, 10 specialty melon cultivars were evaluated, in both certified organic and conventionally managed fields, including: Creme de la Creme and San Juan ananas melon (C. melo var. reticulatus), Brilliant and Camposol canary melon (C. melo var. inodorus), Ginkaku and Sun Jewel asian melon (C. melo var. makuwa), Arava and Diplomat galia melon (C. melo var. reticulatus), and Honey Pearl and Honey Yellow honeydew melon (C. melo var. inodorus). ‘Athena’ cantaloupe (C. melo var. reticulatus) was included as a control. ‘Sun Jewel’, ‘Diplomat’, ‘Honey Yellow’, and ‘Honey Pearl’ were early maturing cultivars that were harvested 10 days earlier than ‘Athena’. ‘Athena’ had the highest marketable yield in the conventional field (10.7 kg/plant), but the yield of ‘Camposol’, ‘Ginkaku’, ‘Honey Yellow’, and ‘Honey Pearl’ did not differ significantly from ‘Athena’. Under organic production, ‘Camposol’ showed a significantly higher marketable yield (8.3 kg/plant) than ‘Athena’ (6.8 kg/plant). ‘Ginkaku’ produced the largest fruit number per plant in both organic (10 fruit/plant) and conventional fields (12 fruit/plant) with smaller fruit size compared with other melon cultivars. Overall, the specialty melon cultivars, except for asian melon, did not differ significantly from ‘Athena’ in terms of marketable fruit number per plant. ‘Sun Jewel’, ‘Diplomat’, and ‘San Juan’ showed relatively high percentages of cull fruit. ‘Honey Yellow’, ‘Honey Pearl’, and ‘Sun Jewel’ exhibited higher soluble solids concentration (SSC) than ‘Athena’ in both organic and conventional fields, while ‘Brilliant’, ‘San Juan’, and ‘Ginkaku’ also had higher SSC than ‘Athena’ under organic production. ‘Honey Yellow’, ‘Sun Jewel’, ‘Brilliant’, and ‘Camposol’ were less affected by powdery mildew (caused by Podosphaera xanthii) and downy mildew (caused by Pseudoperonospora cubensis) in the conventional field. ‘Honey Yellow’ and ‘Camposol’ also had significantly lower aboveground disease severity ratings in the organic field compared with ‘Athena’, although the root-knot nematode (RKN) (Meloidogyne sp.) gall rating was higher in ‘Honey Yellow’ than ‘Athena’.

Summary A simple mathematical model to predict dehydration and impregnation process during osmotic dehydration of orange-fleshed honeydew in sucrose and corn syrup solutions was proposed. Results showed low dispersion and a good fitting capability for WL and SG kinetics. Diffusivity values for WL ranged from 0.96 × 10−10 to 2.22 × 10−10 and 1.04 × 10−10 to 3.10 × 10−10 m2 s−1 in corn syrup and sucrose solutions, respectively. For SG, the obtained range was 0.72 × 10−10 to 2.35 × 10−10 and 0.71 × 10−10 to 2.46 × 10−10 m2 s−1 in corn syrup and sucrose solutions, respectively. The half-life of dehydration rates (t1/2) was from 30.9 to 71.2 min and from 19.4 to 57.5 min in corn syrup and sucrose solutions, respectively. Diffusivities values obtained according to the proposed model were close to the ones observed from diffusive model; t1/2 was a promising criterion for the process time definition.

The Cucumis melo L. inodorus honeydew melon variant is one of the most consumed melons in the USA, and has important commercial and nutritional value. There is a need for improvement of several genetic traits in the US honeydew melon, such as nutrition, drought tolerance, and disease resistance. We investigated the existing regeneration media and optimized the medium composition for an elite honeydew diploid breeding line, “150”, using cotyledonary explants. Four combinations of three different plant growth regulators, 6-benzyladenine, abscisic acid, and indole-3-acetic acid (IAA), were tested in the shoot regeneration media. The presence of IAA in the medium caused the cotyledon explants to curl away from the medium, which made antibiotic selection problematic in our previous study. Omission of IAA from the culture media eliminated this problem and did not impact the shoot regeneration capacity of the cotyledonary explants. We also estimated the ploidy of regenerated plants using flow cytometry, and 50–60% were found to be polyploid (tetraploid or mixoploid). However, contrary to other studies, these polyploid plants did not show major morphological differences compared to the diploid plants.

Using a previously reported optimized Agrobacterium tumefaciens-mediated transformation protocol, a watermelon phytoene synthase-C (PSY-C) gene was introduced into the elite honeydew breeding line ‘150’. Putative transformants were selected on kanamycin-containing medium (from 150 to 50 mg·l−1) and presence of the transgene was confirmed using polymerase chain reaction (PCR). Moreover, Southern blot analysis confirmed integration of the transgene and revealed presence of one to two copies of the PSY-C transgene in the different transgenic lines. In addition, reverse transcription (RT)-PCR analysis revealed transcript levels of the transgene in different tissues of these transgenic lines. Using flow cytometric analysis, it was found that all T0 transgenic plants were tetraploid. Moreover, altered phenotypes (color change) were observed for rind tissues of transgenic lines. Based on high performance liquid chromatography (HPLC), β-carotene content and phytoene accumulation in fruit of transgenic lines were 32-fold and 11 μg·g−1 FW higher than the levels found in the control plants.

Cantaloupe and honeydew melon cultivars were processed and stored under a high oxygen passive modified atmosphere packaging (MAP) or reduced oxygen controlled atmosphere (CA; 5 kPa O2 + 10 kPa CO2 and balance N2) for 14 days at 5 °C. Atmosphere did not affect softening rate or soluble solids content and had a negligible effect on colour. Volatile compounds known as flavour-important in melons were extracted using stir bar sorptive extraction (SBSE) and quantified via GC-MS. Acetate esters increased more in MAP than in CA. Non-acetate esters increased markedly in both cultivars and storage types. Alcohols were more abundant in honeydew than in cantaloupe. Aldehydes decreased during storage in both cultivars and storage types. Lower O2 availability under CA conditions likely suppressed some of the esters relevant to the aroma of fresh-cut melon. Results suggest that package O2 levels are more important in determining aroma than other quality attributes of fresh-cut melon, and high O2 levels may be required to reveal desirable aroma compounds.

Field and laboratory bioassay studies were conducted to determine the impact of Brassicaceae cover crops on cucurbit germination percentages and stand counts. A 2-year field study in southwestern Michigan examined the effect of oilseed radish (Raphanus sativus var. oleiferus), oriental mustard (Brassica juncea), and yellow mustard (Sinapis alba) green manures on muskmelon (Cucumis melo Group reticulatus) stand. All three cover crops reduced direct-seeded muskmelon stand count as well as transplant survival. Stand count for direct- seeded muskmelon was greater than 85% for control and methyl bromide treatments and less than 41% for cover crop treatments. Oilseed radish had the greatest effect with 0% muskmelon stand in both years. The use of transplants improved muskmelon stand establishment. However, stand count (less than 45% to 50%) was still unacceptable. In bioassays, muskmelon, cucumber (Cucumis sativus), and honeydew melon (Cucumis melo Group inodorus) seeds were exposed to either non-lyophilized or lyophilized root and shoot aqueous extracts of oilseed radish. Germination percentages and radicle elongation measurements showed both extracts impacted all three crops to varying degrees. Muskmelon germination was least sensitive to the extracts, followed by cucumber, then honeydew. Cucumber and muskmelon root growth was equally inhibited by non-lyophilized shoot extract, while honeydew growth was mildly stimulated at 5% and 12.5% concentrations. Overall, non-lyophilized root extract showed stronger inhibition on seed germination than non-lyophilized shoot extract, while the reverse was true of lyophilized extracts. In general, non-lyophilized extracts had far greater impact on germination percentages and radicle elongation than lyophilized extracts. These results suggest species and tissue dependent toxicity of the cover crops as well as differential susceptibility of the cucurbit crops tested. Therefore, a plant-back period longer than the 8 days used in this study should be observed after cover crop incorporation before cucurbit seeding or transplanting.

Although melon aromas have been extensively analysed, to our knowledge no GC–O investigations have been published on honeydew melon. An aroma extract of honeydew melon (Cucumis melo var. inodorus) was obtained by hydrodistillation under vacuum followed by solid-phase extraction, and analysed by GC–MS/O and GC–MS. Forty-two volatiles were positively identified, seven of which are reported for the first time in melon. The major volatiles were mostly saturated and unsaturated C9 alcohols and aldehydes. The levels of the corresponding acetates were too low to be detected by classical GC–MS analysis. However, using a sensitive and selective GC–MS/MS method, (E,Z)-2,6-nonadienyl acetate was identified for the first time in melon. Aroma extract dilution analysis (AEDA) of the extract revealed that (E,Z)-2,6-nonadienal was the most impactful compound of honeydew melon. AEDA results also showed that (Z,Z)-3,6-nonadien-1-ol and phenylethyl alcohol imparted fresh and sweet-floral characters, respectively, to honeydew aroma. Copyright © 2009 John Wiley & Sons, Ltd.

We aimed to assess spontaneous food preferences in captive white-handed gibbons and to analyze whether they correlate with nutrient composition. Via a 2-alternative choice test, we repeatedly presented 3 male Hylobates lar with all possible binary combinations of 10 types of food that are part of their diet in captivity and found the following rank order of preference: grape > banana = fig > apple > pear > honeydew melon > carrot > tomato > cucumber > avocado. Correlational analyses revealed a highly significant positive correlation between the food preference ranking and the total carbohydrate, fructose, and glucose contents of the foods (p 0.05). Our results suggest that captive white-handed gibbons are not opportunistic, but selective feeders with regard to maximizing net gain of energy because only the content of carbohydrates, but not the contents of total energy, proteins, or lipids significantly correlate with the displayed food preferences. Further, the results suggest that captive Hylobates lar, in contrast to their free-ranging conspecifics, do not display marked changes in their food selection across the day.

Cucumis melo var. inodorus seeds were found to contain 4.5% moisture, 25.0% crude fat, 25.0% crude protein, 23.3% crude fiber, 2.4% ash and 19.8% carbohydrate. The iodine and saponification values, and unsaponifiable matter and free fatty acid contents of freshly extracted honeydew melon seed oil were 153.4 g I2/100 g oil, 210.2 mg KOH/g oil, 0.9 and 2.5%, respectively. The oil had a color index of 1.6Y + 0.4R, and had 10 fatty acids, of which 86.1% were unsaturated. Linoleic acid predominated with 69.0% followed by oleic acid (16.8%) and palmitic acid (8.4%). LLL (24.9%), OLL (21.5%), PLL (15.9%) and POL (12.4%) (where L, O, P and S denote linoleic, oleic, palmitic and stearic acids, respectively) were the major triacylglycerols present. The melting and crystallization temperatures were −5.12 and −59.01C, respectively. Electronic nose analysis showed the presence of more volatile compounds compared to refined sunflower oil, an oil rich also in linoleic acid.

An immuno-capture polymerase chain reaction (IC-PCR) method for detection of Acidovorax avenae subsp. citrulli (AAC), the causal organism of bacterial fruit blotch (BFB) of watermelon, was developed by combining the immunosorbent enrichment (ISE) method with classical PCR and comparing with the direct PCR and growth check methods. The results showed that all A. avenae subsp. citrulli strains tested have produced 360 bp specific fragments using IC-PCR and direct PCR methods, while other strains from 10 different genera showed negative PCR results. The minimum detection concentration was about 50–100 cfu/ml and 104 cfu/ml, respectively. The IC-PCR sensitivity was 100 times higher than that of direct PCR. The examination of seven batches of different melon seeds from the markets by IC-PCR showed that one cantaloupe, two honeydew melon and two watermelon seed varieties carried the pathogen, indicating that the IC-PCR is an accurate, sensitive, rapid and low-cost technique.

SummaryRecent declines in honey bee populations have created deficiencies in agricultural pollination, and motivated the search for alternatives to traditional honey bee colonies. Mini-nucleus colonies (mininucs), small honey bee hives containing a few hundred workers, are easier and cheaper to set up, maintain and transport than regular sized colonies. We tested whether mininucs can provide effective agricultural pollination in enclosures. We compared the efficiency of mininucs vs. regular Langstroth colonies in pollinating honeydew melons in tunnel net-houses. Flower visit frequencies were higher in net-houses with regular hives than in those with mininucs, but fruit weight and density were not affected by colony type. We suggest that mininucs can effectively pollinate melons in enclosed spaces, and that their ease of handling and non-aggressive behaviour further increases their appeal for agricultural pollination.

Consumers are being advised to increase their consumption of fruits and vegetables to reduce their risk of chronic disease. However, to achieve that goal, consumers must be able to implement protocols in their kitchens to reduce their risk of consuming contaminated produce. To address this issue, a study was conducted to monitor the fate of Escherichia coli O157:H7 and Salmonella on produce (cantaloupe, honeydew melon, carrots, and celery) that were subjected to brushing or peeling using common kitchen utensils. Removal of similar levels of Salmonella from carrots was accomplished by peeling and by brushing, but significantly greater removal of E. coli O157:H7 from carrots was accomplished by peeling than by brushing under running water (P0.05). Brushing removed significantly fewer pathogens from contaminated cantaloupes than from other produce items (P0.05), suggesting that the netted rind provided sites where the pathogen cells could evade the brush bristles. A Sparta polyester brush was less effective than a scouring pad for removing Salmonella from carrots (P0.05). In all cases, brushing and peeling failed to eliminate the pathogens from the produce items, which may be the result of contamination of the utensil during use. High incidences of contamination (77 to 92%) were found among peelers used on carrots or celery, the Sparta brush used on carrots, and the scouring pad used on carrots and cantaloupe. Of the utensils investigated, the nylon brush had the lowest incidence of pathogen transference from contaminated produce (0 to 12%). Transfer of pathogens from a potentially contaminated Sparta brush or peeler to uncontaminated carrots did not occur or occurred only on the first of seven carrots processed with the utensil. Therefore, risk of cross-contamination from contaminated utensils to uncontaminated produce may be limited.

The dielectric properties of foods are important in understanding and modeling their behavior in radio-frequency (RF) and microwave processing, heating, and cooking of food materials. They are important because they influence the absorption of energy from the high-frequency electric fields and the conversion to heat. Thus, they are also important in the design of RF and microwave processing equipment and in the design of foods and meals intended for microwave preparation. Some food materials were selected to illustrate the behavior of their dielectric properties with respect to frequency, temperature, and moisture content. Included are ground wheat; fresh fruits such as banana, apple, cantaloupe, honeydew melon, and watermelon; some food ingredients; and fresh chicken meat. The importance of dielectric relaxation and ionic conduction is discussed in explaining the behavior of food dielectric properties with respect to frequency and temperature.

Extending the production season of melons (Cucumis melo L.) by using very early and late planting dates outside the range that is commercially recommended will increase the likelihood of developing a stronger melon industry in South Carolina. The objective of this study was to determine if early (February) transplanted melons or later (June through July) planting dates are effective in extending the production season of acceptable yields with good internal quality of the melon cultivars: Athena, Eclipse, and Sugar Bowl and Tesoro Dulce (a honeydew melon). Melons were transplanted in Charleston, S.C., in 1998, 1999, and 2000 on 12 and 26 Feb., 12 and 26 Mar., 9 and 23 Apr., 7 and 21 May, 4 and 18 June, and 2 July and required 130, 113, 105, 88, 79, 70, 64, 60, 60, 59, and 56 days from field transplanting to reach mean melon harvest date, respectively. Stands were reduced 67%, 41%, and 22% in the 12 and 26 Feb. and 12 Mar. planting dates, respectively, in contrast to the 26 Mar. planting date but ≤15% in all other planting dates. Planting in February had no earliness advantage because the 12 and 26 Feb. and 12 and 26 Mar. planting dates, all reached mean melon harvest from 19 to 23 June. Comparing the marketable number of melons produced per plot (averaged over cultivar) of the standard planting dates of 12 and 26 Mar. indicated decreases of 21%, 32%, 36%, 36%, 57%, 57%, and 54%, respectively with the planting dates of 9 and 23 Apr., 7 and 21 May, 4 and 18 June, and 2 July. The most productive cultivar of all was `Eclipse', which yielded significantly more melons per plot in all 11 planting dates followed by `Athena' (in 8 of 11 planting dates), `Tesoro Dulce' (7 of 11 planting dates), and `Sugar Bowl' (2 of 11 planting dates). In our study, any planting date with melon quality less than the USDA standard of “good internal quality” or better (Brix ≥9.0) was considered unacceptable because of potential market rejection. Therefore, the earliest recommended planting date with acceptable yield and “good internal quality” was 12 Mar. for all cultivars; the latest planting dates for `Athena', `Eclipse', `Tesoro Dulce', and `Sugar Bowl' were 4 June, 18 June, 7 May, and 9 Apr., respectively. With these recommendations, the harvest season of melons lasted 40 days from 24 June to 3 Aug. for these four cultivars, which extended the production season an additional 2 weeks longer than the harvest date of last recommended 21 May planting date.

Increases in phospholipase D [PLD (EC 3.1.4.4)] and lipoxygenase [LOX (EC 1.13.11.12)] activities are thought to play a critical role in senescence of mesocarp tissues in netted and nonnetted muskmelon (Cucumis melo L.) fruits. We have cloned and characterized two full-length cDNAs, CmPLDα1 and CmLOX1, encoding PLDα and LOX proteins in honeydew melon (C. melo Inodorus Group cv. Honey Brew). Relative levels of expression of the corresponding genes were determined by semi-quantitative RT-PCR in developing and mature fruit mesocarp tissues [20-60 d after pollination (DAP)], as well as in roots, leaves, and stems from 4-week-old and flowers from 6- to 7-week-old plants. The coding regions of CmPLDα1 and CmLOX1 cDNAs are, respectively, 2427 and 2634 nucleotides long, encoding proteins 808 and 877 amino acids in length. CmPLDα1 is very similar to PLDα genes from castor bean (Ricinis communis L.), cowpea (Vigna unguiculata L.), strawberry (Fragaria ×ananassa Duch.) and tomato (Lycopersicon esculentum Mill.) (77% nucleotide identity), and is the first PLD gene cloned from a cucurbit species. CmLOX1 has 94% nucleotide identity to a cucumber (Cucumis sativus L.) LOX gene expressed in roots and 80% identity to cucumber cotyledon lipid body LOX. In general, transcript of CmPLDα1 was much more abundant than that of CmLOX1, but relative levels of transcript in the various organs and tissues were similar for the two genes. Expression was highest in roots, flowers, and fruit mesocarp tissues. CmPLDα1 expression in fruit was essentially constitutive throughout development, although maximum levels occurred at 50 and 55 DAP, respectively, in middle and hypodermal mesocarp. CmLOX1 expression was generally higher in middle than in hypodermal mesocarp with maximum transcript levels occurring at 55 and 50 DAP, respectively. Overall, the patterns of expression of CmPLDα1 and CmLOX1 are consistent with a model in which their encoded enzymes act in tandem to promote or accelerate senescence in fruit mesocarp tissues.

Dielectric properties of three honeydew melon cultivars, grown and harvested to provide a range of maturities, were measured with an open-ended coaxial-line probe and impedance analyzer over the frequency range from 10 MHz to 1.8 GHz. Probe measurements were made on the external surface of the melons and also on tissue samples from the edible internal tissue. Moisture content and soluble solids content (SSC) were measured for internal tissue samples, and SSC (sweetness) was used as the quality factor for correlation with the dielectric properties. Individual dielectric constant and loss factor correlations with SSC were low, but a high correlation was obtained between the SSC and permittivity from a complex-plane plot of dielectric constant and loss factor, each divided by SSC, for both the external surface and internal tissue measurements. However, SSC prediction from the dielectric properties by these relationships was not as high as expected. Permittivity data (dielectric constant and loss factor) for the melons are presented graphically to show their relationships with frequency for external surface and internal tissue measurements. A dielectric relaxation for the external surface measurements, which is attributable to bound water and Maxwell-Wagner relaxations, is also illustrated. Coefficients of determination for complex-plane plots, moisture content and SSC relationship, and penetration depth are also shown graphically. Further studies are needed for determining the practicality of sensing melon quality from the dielectric properties.

Honeydew melons were grown and harvested with a range of maturities for measurement of tissue permittivities (dielectric constant and loss factor) to study possible correlations between the dielectric properties and soluble solids (sweetness) for nondestructive sensing of maturity. Permittivities of tissue samples from 38 melons were measured at 25°C over the frequency range from 10 MHz to 1.8 GHz along with refractometer determinations of soluble solids content (SSC), tissue density, and moisture content. A high correlation (r = 0.96) was found between SSC and the permittivity as expressed in a complex-plane plot of the two components of the relative complex permittivity, each divided by SSC. Through this mathematical relationship, SSC can be calculated from measured permittivity values independent of tissue density and moisture content. Moderate correlations were noted between dielectric constant and SSC at 10 MHz and between the loss factor and SSC at 1.8 GHz. Correlations between the dielectric properties and both moisture content and tissue density were very low. The correlation between tissue density and SSC was also very low. A high correlation was noted between SSC and moisture content, with SSC decreasing as moisture content increased. Problems in using the high correlation between permittivity and SSC for practical, nondestructive sensing of honeydew melon maturity as determined by SSC are also considered.

A phage cocktail was applied to honeydew melon pieces 1, 0.5, and 0 h before contamination with Listeria monocytogenes strain LCDC 81-861 and 0.5, 1, 2, and 4 h after contamination. The phage application was most effective when applied 1, 0.5, or 0 h before contamination with L. monocytogenes, reducing pathogen populations by up to 6.8 log units after 7 days of storage. This indicates that under commercial conditions, if contamination occurs at the time of cutting, phage would have to be applied as soon as possible after cutting the produce. However, all phage applications from 1 h before to 4 h after contamination and all phage concentrations ranging from 10(4) to 10(8) PFU/ml reduced bacterial populations on honeydew melon pieces. Higher phage concentrations were more effective in reducing pathogen populations. A phage concentration of approximately 10(8) PFU/ml was necessary to reduce the pathogen populations to nondetectable levels immediately after treatment, and pathogen growth was suppressed by phage concentrations of 10(6) through 10(8) throughout the storage period of 7 days at 10 degrees C. In an attempt to enhance the effectiveness of the phage cocktail on low pH fruit, such as apples, the phage was applied in combination with MnCl2. This combination, however, did not enhance the effectiveness of the phage on apple tissue. The results from this study indicate that the effectiveness of the phage application on honeydew melon pieces can be optimized by using a phage concentration of at least 10(8) PFU/ml applied up to 1 h after processing of the honeydew melons.

Freshly cut honeydew chunks were dipped for 30 s in a solution containing 1.9 mM hypochlorous acid (ClO) without or with a 40 mM concentration of calcium (Ca) propionate, Ca amino acid chelate formulation (Ca chelate), calcium chloride (CaCl2), or not treated. Respiration and ethylene production rates, firmness, translucency, microbiological and sensory characteristics, surface color, volatile abundance, and tissue calcium content were evaluated during 7 d at 10 8C. Nontreated samples developed the highest respiration and ethylene production rates during storage, followed by samples dipped in ClO, ClO /CaCl2 or ClO /Ca chelate, and ClO /Ca propionate. Calcium salt and chelate treatments more than doubled tissue Ca content and inhibited changes in melon firmness, surface color, and the development of tissue translucency during storage. Treatment with ClO alone increased tissue translucency development, but inhibited surface microbial development. Microbial development was higher on nontreated melon samples than on ClO /Ca propionate-treated samples. Total quality-associated volatile abundance increased throughout storage and was higher in ClO /Ca propionate-treated samples than in other treated and nontreated samples. No sensorial preference was observed by consumer panels among ClO-, ClO /Ca propionate-, or ClO /Ca chelate-treated samples. The results indicate that a sanitary dip with Ca is a better alternative to a sanitary dip alone for quality maintenance and shelf-life stability of fresh-cut honeydew melon tissue. Published by Elsevier B.V.

The fresh-cut produce industry has been the fastest-growing portion of the food retail market during the past 10 years, providing consumers with convenient and nutritious food. However, fresh-cut fruits and vegetables raise food safety concerns, because exposed tissue may be colonized more easily by pathogenic bacteria than intact produce. This is due to the higher availability of nutrients on cut surfaces and the greater potential for contamination because of the increased amount of handling. We found that applied Listeria monocytogenes populations survived and increased only slightly on fresh-cut Red Delicious apples stored at 10°C but increased significantly on fresh-cut honeydew melons stored at 10°C over 7 days. In addition, we examined the effect of lytic, L. monocytogenes -specific phages via two phage application methods, spraying and pipetting, on L. monocytogenes populations in artificially contaminated fresh-cut melons and apples. The phage mixture reduced L. monocytogenes populations by 2.0 to 4.6 log units over the control on honeydew melons. On apples, the reduction was below 0.4 log units. In combination with nisin (a bacteriocin), the phage mixture reduced L. monocytogenes populations by up to 5.7 log units on honeydew melon slices and by up to 2.3 log units on apple slices compared to the control. Nisin alone reduced L. monocytogenes populations by up to 3.2 log units on honeydew melon slices and by up to 2.0 log units on apple slices compared to the control. The phage titer was stable on melon slices, but declined rapidly on apple slices. The spray application of the phage and phage plus nisin reduced the bacterial numbers at least as much as the pipette application. The effectiveness of the phage treatment also depended on the initial concentration of L. monocytogenes .

AIM: To establish whether or not carvacrol and cinnamic acid delay microbial spoilage of fresh-cut fruit. METHODS AND RESULTS: Dipping of fresh-cut kiwifruit in carvacrol solutions at 5-15 mM reduced total viable counts from 6.6 to < 2 log cfu g-1 for 21 d at 4 degrees C; however, undesirable colour and odour changes were also observed. Treatment with 1 mM of carvacrol or cinnamic acid reduced viable counts on kiwifruit by 4 and 1.5 log cfu g-1 for 5 d at 4 degrees C and 8 degrees C, respectively. Treatment of fresh-cut honeydew melon with 1 mM of carvacrol or cinnamic acid extended the lag phase of the microbial flora from less than 1 d in the untreated controls to 3 d at 8 degrees C and 5 d at 4 degrees C. Viable counts on the treated melon were 6 log cfu g-1 lower on Day 3 at 8 degrees C and 4 log cfu g-1 lower on Day 5 at 4 degrees C, compared with the untreated controls. IMPACT OF THE STUDY: Treatment with 1 mM of carvacrol or cinnamic acid delays spoilage of fresh-cut kiwifruit and honeydew melon at chill temperatures without adverse sensory consequences.

The research evaluates the influence of some selected rootstocks on the C. melo L. subsp. melo var. inodorus H. Jacq. (honeydew melon) cv. Incas fruit quality. Four Cucurbita maxima×. Cucurbita moschata hybrids (namely Polifemo, AS10, RS841 and P360) and two genotypes of melon (Energia and Sting), selected for their disease resistance, were tested as rootstocks under greenhouse conditions. Physical properties, chemical data, volatile constituents and sensory descriptors were used for quality determination. All the used rootstocks exhibited a good affinity with the scion, with Polifemo and RS841 showing a productivity higher (about 15%) and a significant increase in fruit weight (about 10%) than the control. As regards the titratable acidity (TA) and the total soluble solids (TSS), similar values resulted among the samples, except for the higher levels of TA in Incas/AS10 and Incas/Sting and the higher of TSS in Incas/AS10. As regards the volatile compounds, the content of key aroma, aldehydes containing a straight nine-carbon chain, such (Z)-3-nonen-1-ol and (Z)-6-nonenal resulted lower in most of the grafted samples (20-60% and 8-45% less than the control, respectively). In relation to the key aroma compounds, the melons grafted on Energia, RS841, P360 and Polifemo rootstocks resulted more similar to the control. 14 sensory descriptors were defined for the appearance, aroma, taste, texture traits, flavor and overall. Energia grafting combination presented the sensory descriptor intensities more close to the ungrafted Incas samples. In conclusion, the quality of the grafted inodorus melon fruits was modified in a different way according to the grafting combinations; RS841 and Polifemo can be successfully used as rootstocks for the inodorus melon since they increased disease resistance and productivity without determining relevant changes on fruity quality. © 2014 Elsevier B.V.

The preparation and distribution of fresh-cut produce is a rapidly developing industry that provides the consumer with convenient and nutritious food. However, fresh-cut fruits and vegetables may represent an increased food safety concern because of the absence or damage of peel and rind, which normally help reduce colonization of uncut produce with pathogenic bacteria. In this study, we found that Salmonella Enteritidis populations can (i) survive on fresh-cut melons and apples stored at 5 degrees C, (ii) increase up to 2 log units on fresh-cut fruits stored at 10 degrees C, and (iii) increase up to 5 log units at 20 degrees C during a storage period of 168 h. In addition, we examined the effect of lytic, Salmonella-specific phages on reducing Salmonella numbers in experimentally contaminated fresh-cut melons and apples stored at various temperatures. We found that the phage mixture reduced Salmonella populations by approximately 3.5 logs on honeydew melon slices stored at 5 and 10 degrees C and by approximately 2.5 logs on slices stored at 20 degrees C, which is greater than the maximal amount achieved using chemical sanitizers. However, the phages did not significantly reduce Salmonella populations on the apple slices at any of the three temperatures. The titer of the phage preparation remained relatively stable on melon slices, whereas on apple slices the titer decreased to nondetectable levels in 48 h at all temperatures tested. Inactivation of phages, possibly by the acidic pH of apple slices (pH 4.2 versus pH 5.8 for melon slices), may have contributed to their inability to reduce Salmonella contamination in the apple slices. Higher phage concentrations and/or the use of low-pH-tolerant phage mutants may be required to increase the efficacy of the phage treatment in reducing Salmonella contamination of fresh-cut produce with a low pH.

Fourier transform infrared photoacoustic spectroscopy (FT-IR/PAS) was used to study edible coatings and microorganisms on fruit surfaces (apple and honeydew melon). In the experiment, pregelatinized starch and whey protein concentrate were used to prepare edible coatings, while Saccharomyces cerevisiae, Lactobacillus casei, Escherchia coli, and Staphylococcus aureus were used for microbial study. The spectra obtained from the edible coatings on the apple surface indicate that the FT-IR/PAS technique can effectively distinguish the coating surface and the food substrate by examination of magnitude, phase angle, and generalized two-dimensional (G2D) correlation spectra. Results reported show the first application of FT-IR/PAS to directly differentiate a fruit surface (apple and honeydew melon) with/without microorganisms without elaborate sample preparation. The results demonstrate the potential of FT-IR/PAS to characterize the presence of microorganisms on fruit surfaces.

Melon samples were equilibrated with solutions of increasing mannitol concentration in the range 0.00 to 0.80 M for the purpose of evaluating turgor pressure through volume change measurement. Melon compression and relaxation behaviors were evaluated with an Instron Testing machine, and structural characteristics were observed through microscopy. Immersion in mannitol solutions affected tissue firmness, reducing its value in all studied cases. After plasmolysis and plasmotypsis, samples became less elastic and more viscous, and firmness reduced more than 50%. Textural parameters obtained and microscopy results indicated that, in general, fracture might be associated with cell-wall integrity, and residual relaxation force might be associated with tissue turgor pressure.

Spatial variation in soluble solids content (SSC) of fruits of apple (Malus ×domestica Borkh. cv. Red Delicious), cantaloupe (Cucumis melo L. Cantaloupensis group), grapefruit (Citrus paradisi Macf. cv. Indian River Ruby Red), honeydew melon (Cucumis melo L. Inodorus group), mango (Mangifera indica L. cv. Hayden), orange (Citrus sinensis L. Osbeck. cv. Valencia), peach (Prunus persica L. Batsch. cv. Windblow), pineapple (Ananas comosus L. Merr. cv. Kew) and tomato (Lycopersicon esculentum Mill.), and of bulbs of onion (Allium cepa L. Cepa group) and in dry-matter content (DMC) of potato (Solanum tuberosum L. cv. Russet Burbank) tubers was measured along three directional orientations (i.e., proximal to distal, circumferentially midway along the proximal to distal axis, and radially from the center of the interior to the outer surface). The pattern and magnitude of constituent variation depended on the type of product and the direction of measurement. Radial and proximal to distal variation was greater than circumferential variation in all the products tested. Honeydew had the highest radial variation with a SSC difference of 6.0 % and a cv of 22.8%, while tomato displayed lower radial variation with a cv of 1.0%. Pineapple had a proximal to distal SSC difference of 4.6% with a cv of 13.8%, while the difference in tomato was 0.6% with a cv of 5.1%. Circumferential variation of SSC in all products tested was cv ranging from 1.1% to 3.8%. The results confirm that considerable constituent variability exists within individual fruit and vegetable organs. This variability may affect the accuracy of calibration equations and their prediction capability. Therefore, within-unit constituent variability should be meticulously assessed when an NIR spectrometric method is being developed for the nondestructive quality evaluation and sorting of a product.

Pieces (1835 mm cylinders) were prepared from sanitized fruits of four honeydew melon varieties (Green Flesh, Morning Ice, Rico, RML 2704) harvested at typical commercial maturity. Pieces were stored in air or controlled atmosphere (CAair15% CO2) at 5°C and evaluated for sensory quality, firmness, color and soluble solids concentration (SSC) after 0, 6 and 12 days. Significant variation was found among varieties in SSC (9.9‐12.2%), firmness (14.0‐19.9 N), and chroma (10.4‐19.0), hue angle (115‐113) and L* (63.7‐66.8) color values of pieces on day 0. Pieces from the four varieties averaged 10 N firmness loss from day 0 to 12 and CA reduced loss significantly in only one variety. During air storage color saturation decreased only in pieces from varieties with high initial chroma (C) values. Average DC between days 0 and 12 was 3.7 for air-stored vs 1.0 for CA-stored pieces. Average DL* was 5.8 and 1.4 for the same conditions, respectively. SSC were maintained during storage in air or CA. Pieces stored in 15% CO2 had higher visual quality scores than those stored in air. In addition, CA storage greatly reduced development of macroscopic decay, translucency and off-odors. © 1998 Elsevier Science B.V. All rights reserved.

Proximate and micronutrient composition of cantaloupe and honeydew melons purchased from six marketing locations at marketing times near maximum and minimum product availability were determined. Cantaloupe varieties purchased at periods near maximum availability showed significantly higher (α= 0.01) levels of niacin, riboflavin, thiamin, ascorbic acid, folacin and Cr compared to those purchased near minimum availability. Honeydew melon varieties purchased at periods near maximum availability showed significantly lower (α= 0.01) levels of ascorbic acid, folacin, pantothenic acid, K, Zn, and Cr compared to those purchased near minimum availability. Although some differences were observed between values obtained and those reported in Handbook 8–9, proximate composition and mean values for micronutrients approximated those previously reported.

The substrate specificity of honeydew melon (Cucumis melo var. inodorus Naud) protease D was studied by the use of synthetic substrates and oligopeptides derived from a protein hydrolyzate. The hydrolysis rates of succinyl-(L-Ala)1-3-p-nitroanilide (Suc-(Ala)1-3-pNA) the hydrolysis rate progressively rose in proportion to the increased chain length. Benzyloxycarbonyl-L-tyrosine p-nitrophenyl ester (Z-Tyr-ONp) and benzoyl-L-tyrosine ethyl ester (Bz-Tyr-OEt) were cleaved by honeydew melon protease D, but benzoyl-L-arginine p-nitroanilide (Bz-Arg-pNA), benzyloxycarbonyl-L-lysine p-nitrophenyl ester (Z-Lys-ONp) and tosyl-L-arginine methyl ester (Tos-Arg-OMe) were not hydrolyzed. Contrary to the results obtained by using synthetic substrates, the carboxyl sides of charged amino acid residues were preferentially cleaved by the enzyme in the oligopeptide substrates. The substrates that had charged or polar amino acids at P2 positions were not cleaved. On the other hand, the non-polar amino acid or proline at P2 were favored for hydrolysis. The information concerning the subsite of protease D was obtained and is useful for synthesis of a good substrate. As it is distinct from molecular mass, the substrate specificity of honeydew melon protease D is most analogous to cucumisin [EC 3.4.21.25] among serine proteases from cucurbitaceous plants.