firm flesh offering 8–12-d shelf life. Nearby pollinizer sources could impart larger seed-bearing fruits. Fruits are ideal for table purposes and for processing. The hallmark features of ‘Dawn Delight’ tissue culture papaya include stable female sex
J.A. Narciso, E.A. Baldwin, A. Plotto, and C.M. Ference
only be accepted by the industry if decay reduction and resulting shelf life extension were very significant, justifying a change in the current harvesting and handling operation. However, postharvest treatments could increase shelf life of processed
Yasutaka Kubo, Kyoko Hiwasa, Willis Omondi Owino, Ryohei Nakano, and Akitsugu Inaba
`La France' pear (Pyrus communis L.) fruit were exposed to chilling temperature (-1 °C) for a week to induce ethylene biosynthesis before they were transferred to 20 °C to allow ripening. On 1, 4, or 7 days after the transfer to room temperature, fruit were treated with 20 μL·L-1 1-MCP for 12 hours. The 1-MCP treatments suppressed ethylene and carbon dioxide production significantly and slowed fruit softening. The shelf life period of fruit with desirable firmness treated with 1-MCP on day 4 was twice that of untreated fruit, with firmness of 1-MCP treated fruit on day 1 being higher than desirable while that of fruit treated on day 7 was lower than desirable. To determine the optimum 1-MCP concentration for treatment, fruit were exposed to 0.01 to 100 μL·L-1 1-MCP 3 days after the transfer to 20 °C. The fruit treated with 1 μL·L-1 1-MCP and less ripened similarly to untreated fruit, having a shelf life of a week. 1-MCP treatments of 10 and 100 μL·L-1 inhibited ethylene and carbon dioxide production, and delayed fruit softening and occurrence of senescent break down. The flesh firmness of these fruit maintained suitable eating quality for more than 3 weeks. Our results indicate that 1-MCP treatment of 10 μL·L-1 at 20 °C 3 to 4 days after initiation of ripening can extend the shelf life of `La France' pear fruit. Chemical name used: 1-methylcyclopropene (1-MCP).
Shannon E. Beach* and Terri W. Starman
Vegetative annuals are increasing in popularity among greenhouse growers and consumers but little is known about their postharvest shelf life. Twenty-two cultivars from ten species of vegetative annuals were grown to marketability with optimum greenhouse culture. Plants were then subjected to one of three shipping durations (0, 1, or 2 days) in simulated shipping i.e., a growth chamber at 26.7 ± 0.3 °C, 0 μmol·m-2·s-1, and 50% relative humidity. The plants were then moved to simulated postharvest environment i.e., growth room at 21.1 ± 1.3 °C and 6 μmol·m-2·s-1 to evaluate shelf life. Flower number and plant quality rating were measured weekly in addition to observations of plant appearances. Some of the postharvest disorders noted on several species and cultivars were stem die back, leaf chlorosis, stem elongation, bud abortion, flower drop, and flower fading. The majority of the cultivars maintained their quality one-week postharvest although flower drop was common. After the first week of shelf life, decline in vegetative and reproductive tissues were noted in most plants. Cultivars from nine species: Argyranthemum frutescens (L.) Sch. Bip, Bracteantha bracteata (Vent.) Anderb. & Haegi, Calibrachoa hybrid Lave Lex, Diascia ×hybrida, Lantana camara L., Nemesia ×hybrida, Petunia ×hybrida, Sutera hybrida, and Sutera cordata showed decreased flower number and/or quality rating due to shipping duration, with increased shipping duration causing accelerated postharvest disorders. The only species unaffected by shipping duration was Angelonia angustifolia Benth.
Mustafa Ozgen, Senay Ozgen, and Jiwan P. Palta
Recent studies from our laboratory have demonstrated that lysophoshatidylethanolamine (LPE) is able to accelerate fruit ripening while at the same time promoting shelf life. LPE is a natural lipid and is commercially extracted from egg yolks and soybeans. We studied the influence of LPE on the pattern of anthocyanin accumulation and storage quality of cranberry fruit (Vaccinium macrocarpon Ait. cultivar Stevens). For this purpose 2 x 2-m plots were established in cranberry beds at two separate locations near Wisconsin Rapids. Experiments were conducted in 1997 and 1998 seasons. Plots were sprayed with LPE (extracted from egg yolk and soybean) 3 to 4 weeks before harvest. Spray solution included 200 ppm LPE, 3% ethanol, and 0.1% detergents (either Tergitol or Sylguard). Fruit samples were taken from a part in the plot periodically to determine the changes in the fruit. The rest of the plots were commercially wet harvested with a machine and stored in cold storage. Marketable fruit were counted at various times of cold storage to determine effect of LPE on shelf life of cranberries. In general, application of LPE from both sources resulted in 20% to 35 % increase in fruit anthocyanin contents. Also LPE treatment resulted in 10% to 20% increase in marketable fruit in cold storage. A postharvest dip of cranberry fruit with 50 ppm LPE solution for 15 min also resulted in about a 20% to 30% increase in marketable berries during cold storage. The results of this study shows that pre- and postharvest applications of LPE can add value to cranberry crop including better and more uniform colored fruit, enhance self life, and earlier harvest.
Jin-He Bai, Robert A. Saftner, and Yuen S. Lee
The development of tissue translucency of fresh-cut honeydew cubes adversely affects product quality and primarily occurs in cubes that have been sanitized by dipping in chlorine water (sodium hypochlorite solution) following processing. Chlorine water dips containing calcium propionate as an antimicrobial salt were tested to decrease tissue translucency and extend the marketable shelf life of honeydew (2-cm cubes) sealed in a rigid container with a film overlap and stored at 10 °C for 7 days. Honeydew cubes not dipped following processing had higher respiration rates and microbial populations than cubes that had been dipped, and lost their marketability on day 5 due to off-odor development. Dipping in chlorine water decreased the initial population and growth of microorganisms on the cubes, compared to dipping in water or not dipping. However, translucency developed in cubes dipped in water, with or without chlorine, and became unsalable by day 5. Chlorine water dips containing calcium propionate were devised that maintained excellent antimicrobial characteristics and prevented translucency in honeydew cubes kept 7 days at 10 °C. Quality analyses revealed that calcium propionate treatments decreased respiration and ethylene production rates, maintained tissue firmness, the lightness and brightness of cube surfaces, melon aroma and overall visual quality through 7 days of storage. The calcium propionate dips did not impart or induce any detectable off-flavors or off-odors to the cubes.
Justin Butcher and Teddy Morelock
Postharvest storage of southernpeas is crucial in the production process. Governed by consumer demands, farmers strive for a product that is high in quality and freshness, and has an appropriate texture and appealing color. Improper storage of southernpeas results in their premature deterioration, lack of acceptance, and possible loss of profit. Therefore, an appropriate storage facility and temperature should be devised that will benefit both farmer and consumer. In an effort to prevent potential losses of southernpeas, a study was conducted to determine the best environmental condition at which to store and to potentially extend shelf life. In 2004, two experiments were conducted on the University of Arkansas Agriculture Research and Extension Center, Fayetteville, Ark., to determine the best genotype and storage environmental condition to maintain a quality marketable prod-uct. In the first experiment, a screening of 23 southernpea genotypes was conducted from single plots to determine which genotypes could maintain their appearance the longest in a refrigerated environment. In the second experiment, two separate plantings were made of five southernpea genotypes in a randomized block design in two separate fields. Upon maturity, 12 mature green pods of each genotype were subjected to a sweated and unsweated treatment. After shelling, seeds were subjected to one of three different environmental conditions: cool regime, room temperature, and ambient air, evaluating each on the basis of changes in physical appearance; a hot water dip treatment was also examined. A refrigerated environment at or near 37 to 41 °F was the best environment to store southernpeas for nearly 2 weeks. The sweated treatment also aided in the shelling process and appeared to maintain the appearance of each genotype longer.
Muharrem Ergun, Donald J. Huber, Jiwon Jeong, and Jerry A. Bartz
The purpose of the present study was to investigate the role of ethylene action, via use of the ethylene antagonist 1-methylcyclopropene (1-MCP), on the senescence and quality of fresh-cut ripe papaya (Carica papaya L. `Sunrise Solo') fruit. Ripe papaya fruit were treated with 2.5 μL·L-1 1-MCP and immediately processed into fresh-cut slices or left intact. At 2-day intervals over 10 days at 5 °C, continuously stored slices were monitored for ethylene production, firmness, electrolyte leakage, color, sensory changes, and pathogen incidence. Slices freshly prepared from intact fruit stored under identical conditions were measured similarly. Ethylene production did not differ significantly between the treatments, although production rates were slightly but consistently higher in slices from intact control compared with intact 1-MCP-treated fruit. Mesocarp firmness of continuously stored slices and slices from fruit stored intact was significantly retained by 1-MCP. Firmness of continuously stored slices from 1-MCP-treated fruit declined 50% compared with 75% for control slices. Firmness of fresh-cut slices prepared from intact control and 1-MCP-treated fruit at each sampling interval declined 26% and 15%, respectively. Electrolyte leakage remained low and changed little in slices freshly prepared from fruit stored intact. Leakage from continuously stored papaya slices increased after 4 days, and after 6 days controls increased significantly compared with stored slices derived from papaya fruit initially treated with the ethylene antagonist. The flesh color of continuously stored slices or slices prepared from fruit stored intact was influenced by 1-MCP only during the later periods of storage. Microbial counts in stored slices or slices prepared at each sampling were generally unaffected by 1-MCP. Informal sensory analysis indicated that the edible shelf life was 6 days in stored slices from 1-MCP-treated fruit compared with 2 to 3 days for stored slices from control fruit.
Dilip R. Panthee and Randy G. Gardner
.sp. lycopersici (Sacc.) Snyd. Hans.] (races 1, 2), and Tomato spotted wilt virus (TSWV). It combines the rin and crimson genes, which improve the shelf life and lycopene content of the tomato fruit, respectively. Origin ‘Mountain Lion’, the F 1 hybrid of
Ivan Simko, Ryan J. Hayes, Krishna V. Subbarao, and Rebecca Grube Sideman
SM09A and SM09B are F 8 romaine breeding lines of lettuce ( Lactuca sativa L.) resistant to the dieback disease and with good shelf life. SM09B was selected from a cross between ‘Darkland’ and PI 491224, whereas SM09A was developed from ‘Green