, optimum CA conditions must be investigated for cultivars used in organic apple production ( Delate et al., 2003 ). The purpose of this work was to investigate the feasibility of improving yield, quality, and storage life of some organically grown apple
Ibrahim I. Tahir and Hilde Nybom
P. Perkins-Veazie, J.K. Collins, and J.R. Clark
The storage life of blackberry fruit is generally `2 to 3 days when stored at 1C. This study was done to determine the maximum storage life among erect blackberry cultivars, and to determine storage temperature effects on storage life. Shiny black fruit from `Navaho', `Arapaho', and `Shawnee' cultivars were stored at 2C, 5C, or 10C for 20, 14, and 7 days, respectively. At any temperature. only 10-20% of `Navaho' fruit had decay, while 30-50% of `Arapaho' and 40-70% of `Shawnee' fruit had decay. Weight loss was 3-5% depending on temperature and was not different among cultivars. Soluble solids concentration did not change during storage but titratable acidity decreased in all cultivars for fruit held at all temperatures. Anthocyanin content increased during storage in `Shawnee' and `Navaho' but not in `Arapaho' fruit. Results indicate that `Navaho' fruit have a longer shelflife than other blackberry cultivars.
Albert F. Eboudwarej and Robert C. Herner
The grape variety `Himrod' under conventional storage practices has a short storage life while it has an excellent quality character.
To modify berry size and cluster compactness, different treatments are being used. Application of these cultural practices has pronounced effect on storage life of grapes. The cultural practices consist of different combinations of gibberellin application (two different concentrations), girdling and cluster thjnning.
Biophysical and biochemical evaluation of the grapes under two different modified storage conditions showed that treated grapes react differently during storage. Our results suggest that grapes that were only treated with gibberellin (20 ppm at shatter and 50 ppm postshatter) were better than control slid any other combined treatments and the worst was the case of only girdling application. Combination of these two treatments were intermediate in terms of biophysical evaluation.
Ruth Ben-Arie and Yohanan Zutkhi
The commercial storage life of the nonastringent Japanese `Fuyu' persimmon (Diospyros kaki L.), grown in Israel, was extended from 6 to 18 weeks at 0C by modified-atmosphere packaging (MAP) in a low-density polyethylene (LDPE) film. MAP retarded fruit softening and inhibited development of peel and flesh disorders, which limited the storage life of the naked fruit. The fruit maintained its external and internal quality within the MAP during a subsequent week at 20C in the 0.08-mm LDPE film. Fruit quality deteriorated more rapidly in a 0.06-mm package. The difference between fruit quality in the two packs is attributed to specific physiological effects of the different atmospheric equilibria established due to film thickness.
Ahmed El Ghaouth, Rathy Ponnampalam, and Joseph Arul
The effect of chitosan coating on the respiration rate, ethylene production and quality attributes of tomatoes stored at 20°C under high humidity-regular atmosphere was investigated. Chitosan coating reduced significantly the respiration rate and ethylene production of tomatoes, with a greater effect at higher concentration. In addition coating modified the internal microatmoaphere of fruits. Furthermore, coated fruits were firmer, higher in titratable acidity, less decayed and their change in color proceeded at a slower rate than the control.
In conclusion chitosan coating delayed senescence and prolonged storage life of tomatoes, without affecting their market quality by acting as diffusion barrier for gases.
Hugo Ramirez, Judith Zambrano, and Eusebio Bracho
They were done studies on the influence of temperature (10, 15 and 24 C) and permeable coatings (Prolong and Primafresh) on the storage life of tomatoes cv `Large River' and `Caribbean'. Fruits were obtained from a commercial source in the Clear River area of the Lara State, at the breaker state. Quality measurements included weight loss, color, titrable acidity, pH, total soluble solids and dry matter. Weight loss was highest in the `Caribbean' cultivar being notorious in the first five days of storage, but it was not observed a meaningful response with respect to permeable coatings. `Large River' developed color early, though it was affected very little by the temperature of 10 C and Prolong. `Caribbean- resulted firmer during all the period of storage and the low temperature. Both cultivars showed equal trend with respect to increase total soluble solids. Dry matter showed a similar trend for both cultivars, temperature and permeable coatings.
Robert C. Ebel, Edward L. Proebsting, and Max E Patterson
`Delicious' apple (Malus domestica Borkh.) trees received regulated deficit irrigation (RDI) early in the growing season to determine if fruit quality and storage life would he altered compared to well-watered trees. Soil moisture and leaf water potential were lower in RDI trees than in those that did not receive RDI most of the season. Internal ethylene concentration increased logarithmically earlier in RDI apples. At harvest, RDI fruit were smaller and had a higher soluble solids concentration (SSC) and lower titratable acidity. Starch degradation was delayed in RDI fruit, and their color was not affected. Firmness was not affected when the effect of size on firmness was removed. The SSC of RDI apples remained higher during storage, but starch content, titratable acidity, firmness, and color were similar.
Jiwon Jeong, Donald J. Huber, and Steven A. Sargent
1-Methylcyclopropene (1-MCP), an inhibitor of ethylene action, has been shown to extend the storage life of avocado fruit. Waxing is also known to extend the storage life of avocado by reducing water loss and modifying the fruit internal atmosphere. In this study, 1-MCP and waxing were used to investigate their effects on ripening characteristics in avocado fruit. Preclimacteric `Tower II' and `Booth 7' avocados were treated with 1-MCP (Ethylbloc®) for 12 h at 20 °C. Half of the fruit were waxed (Sta-Fresh 819F®, FMC Co.) after 1-MCP treatment. The fruit were subsequently stored at 13 °C or 20 °C at 85% RH. As evaluated by fruit firmness, ethylene evolution, and respiration rate, 1-MCP and waxing delayed the ripening of `Tower II' avocados stored at 20 °C. Fruit treated with both 1-MCP and wax had better retention of green peel color and fruit firmness, and the delayed climacteric pattern of ethylene evolution and respiration rates. Waxing reduced weight loss and retarded softening, but did not delay climacteric ethylene evolution and respiration rates. Whereas firmness of control fruit decreased from >100 N to 20 N in as few as 7 days at 20 °C, fruit treated with both 1-MCP and wax reached 20 N over 11 days at 20 °C. The firmness of `Booth 7' avocados treated with both 1-MCP and wax decreased from >170 N to 20 N over a 5-week period at 13 °C. Current studies are addressing the nature of the dramatic decrease in firmness of MCP-treated fruit.
Ji Gang Kim*, Yaguang Luo, Yang Tao, and Kenneth C. Gross
The effects of 1-methylcyclopropene (MCP), sanitizer and their combination on ethylene action, microbial growth and storage life of fresh-cut cilantro were studied. Fresh cilantro was treated with 1.5 μL·L-1 MCP for 18 hours at 10 °C. The treated and nontreated cilantro leaves were cut and washed in water, chlorine, and mixed solution of sodium chlorite and citric acid (SANOVA). Samples were dried, packaged with 29.2μmol·kg-1 Pa s oxygen transmission rate films, and stored for 14 days at 5 °C. Results indicated that MCP affected respiration rate of fresh-cut cilantro and the headspace gas composition (O2 and CO2) of sample packages. The combined treatment had lower tissue electrolyte leakage and ethanol concentration, and delayed color changes during storage. SANOVA and the combination of MCP and SANOVA were effective in reducing aerobic microbial population and coliform population. Samples treated with MCP and SANOVA had good quality with high overall quality score at the end of storage.
R. Couture, M.I. Cantwell, D. Ke, and M.E. Saltveit Jr.
Relationships between storage quality attributes, such as russet spotting and browning intensity, and physiological attributes, such as soluble phenolic content and polyphenol oxidase (PPO) and phenylalanine ammonia-lyase (PAL) activities, of minimally processed crisphead lettuce (Lactuca sativa L.) were studied. The processed lettuce tissue was kept in air or air plus ethylene at 2 or 5 μl·liter-1 at 2.5 or 5C for 1 to 4 days and then transferred to air at 2.5, 5, or 20C for 1 to several days. None of the above physiological attributes of the initial samples from eight lettuce cultivars (Calmar, El Toro, Sea Green, Pacific, Monterey, Salinas 88, 86-13, and Nerone) and three maturity stages (immature, mature, and overmature) correlated with their storage quality. However, ethylene-induced PPO and PAL activities and browning intensity measured 3 to 4 days after harvest consistently and significantly correlated with the final visual quality of the ethylene-treated, minimally processed lettuce after 6 to 10 days of storage. Among these three attributes, ethylene induced a 2.5- to 5.3-fold increase in PAL activity, while the relative changes in PPO activity and browning intensity were only 23% to 68%. Ethylene-induced PAL activity possibly may be used as an index to predict the storage life of minimally processed lettuce.