Regular Cold Storage Research Articles

Automation of Refrigeration Systems for Extending Shelf life of Fruits and Vegetables in Remote Areas for Economically Weaker Section

India is an agricultural country. During lockdown, there had been a big problem transporting the productionto cold storages. Considering the problem of villagers, a low cost and affordable refrigeration system is proposedhere. The time and cost of transportation through the cold chain and the storage are thus saved. This cold storageis automated to control the environmental conditions suitable for extending life of fruits and vegetables. It uses amicrocontroller to control humidity, temperature and CO2 level which is appropriate for the commodity to bestored by the farmer. It alerts the farmer before the expiry date of the stored commodity through a message on thephone number linked with the storage. It uses the water obtained from condensation on cooling ducts for humiditycontrol. To maintain the optimum level of CO2 inside the chamber, fresh air is circulated at regular intervals oftime. It consumes same power as a refrigerator would consume. It does not require continuous water supply orammonia as in regular cold storage systems. It can be easily customized for a particular user.

‘WA 38’ Apple

‘WA 38’ (‘Enterprise’ · ‘Honeycrisp’) is a new apple selection from the Washington State University apple breeding program with commercial potential based on its exceptional eating quality, its large fruit size, attractive appearance, and its productivity. It is very attractive with 90% of the skin surface covered by dark red–purple blush over a green–yellow background. It is significantly more crisp and juicy eaten both fresh and out of storage when compared with commercial cultivars. Unlike many existing cultivars, it has little reduction in quality, particularly firmness, after several months in regular cold storage. It ripens in late September in Wenatchee, WA, and its vigor and productivity fall within the range of existing commercial cultivars. Its cut flesh shows very low enzymatic browning, making it suitable for fresh-cutslice packaging and for use in salads. It is suited to the fresh market both directly off the tree and out of mediumand long-term storage.

A simple pretreatment with low O2 to alleviate superficial scald in Granny Smith apples

AbstractSealing Granny Smith apples in a low‐O2 atmosphere for 7 days at 20 °C (LO2‐20C) prior to cold storage reduced superficial scald development after 6 and 8 months at 0 °C plus 10 days at 20 °C. This LO2‐20C treatment reduced the O2 levels that induce endogenous production of significant amounts of CO2, acetaldehyde and ethanol, and thereby reduced ethylene production in cold storage, which in turn reduced scald development. Treatment with ethanol vapour (20 mL L−1) for 1 day at 20 °C plus 6 days at 1 °C or with low O2 for 1 day at 20 °C plus 6 days at 1 °C (LO2‐1C) did not reduce scald effectively. 1‐Methylcyclopropene (1‐MCP) treatment at 0.5 µL L−1 was the most efficient at reducing scald development. In all treatments, superficial scald development proceeded from the distal blossom end towards the proximal stem end of fruits. After 6 months of cold storage at 0 °C, peel browning and membrane leakage, measured as electrical conductivity in situ, were greater at the blossom end than at the stem end of control, ethanol‐ and LO2‐1C‐pretreated fruits. In LO2‐20C‐ and 1‐MCP‐pretreated fruits, colour indices (hue angle, lightness and chroma) and electrolyte leakage were similar at both the stem and blossom ends and were associated with less scald development after 6 months at 0 °C. The reduction in scald development was also associated with lower peroxidase and polyphenol oxidase activities in the peel of LO2‐20C‐ and 1‐MCP‐pretreated fruits. A simple treatment at 20 °C (LO2‐20C) prior to regular cold storage could also be suitable for organically grown apples that cannot be treated with diphenylamine or 1‐MCP. Copyright © 2007 Society of Chemical Industry

1-MCP treatment preserves aroma quality of ‘Packham's Triumph’ pears during long-term storage

The effects of 1-MCP and CA storage in aroma production and consumer acceptance, were investigated during the long-term storage of ‘Packham‘s Triumph’ pears. Pears were harvested 144 (Harvest 1) and 157 days (Harvest 2) after full bloom. The fruit were stored under cold storage (0 °C, 90–95% R.H.), controlled atmospheres (CA, 2.0–2.5 kPa O 2 and 1.0–1.5 kPa CO 2) or treated at harvest with 1-MCP (0.2 μL L −1) followed by cold storage. Ripening indices and aroma volatile production (using SPME technology) were determined after 2, 4 and 6 months of storage plus 5 days of shelf life, in addition to sensory evaluations. Butyl and hexyl acetate, followed by pentyl acetate and butyl butanoate, were the most abundant esters produced by the pears, and butanol and hexanol the most abundant alcohols. Their abundance increased during the development of ripening. Hexyl acetate with fruity notes was found to be the main contributor to the aroma of the pears, followed by butyl acetate and pentyl acetate, while alcohols showed a poor contribution. After 2 months of storage, pears stored under regular cold storage developed the highest content of volatile compounds and also the highest odour value, being preferred by sensory panelists. CA storage and 1-MCP treatment reduced the production of aromatic volatiles by the fruit. Nevertheless, after a longer storage period, pears treated with 1-MCP or stored under CA conditions, recovered capacity for volatile production with odour activity, and the panelists preferred 1-MCP treated over CA stored fruit. Pears treated with 1-MCP from the late harvest date were capable of producing higher amounts of volatile compounds during storage than those harvested at the commercial peak. The treatment of pears with 1-MCP followed by cold storage maintained textural characteristics preferred by the consumers and the capacity of volatile production, and therefore this technology could be used for maintaining fruit quality during long-term storage.

Economic aspects of alternatives to methyl bromide in the postharvest and quarantine treatment of selected fresh fruits

Methyl bromide is the most commonly used postharvest and quarantine treatment of temperate fruit worldwide. Low costs, short fumigation times, and consistent quarantine security are the main reasons for methyl bromide's dominance. Recent environmental issues and laws have created the need for an alternative to methyl bromide for postharvest and quarantine treatment of fresh fruits. The objective of this study was to analyze alternative treatment scenarios with capabilities equal to those achieved by methyl bromide for treatment of apples, sweet cherries, nectarines, peaches, and plums. Partial budget scenarios for each commodity were developed to determine the methyl bromide treatment costs which established a benchmark scenario to compare to the alternative treatment scenarios of each commodity. Irradiation was the only alternative identified that was available for all the fruits in this study. Cost increases for all fruit treated with irradiation ranged from two to 14 times methyl bromide costs. Controlled atmosphere storage for apples had cost increases of 122% over methyl bromide costs. Costs for regular cold storage for apples was 93% of the benchmark cost. However, the reduced costs of suppressing the pests resulted in a marketing window of only four months since there is an eight-month limit on regular cold storage and four months were required for suppressing the pests.

565 Evaluation of the Massive Use of Magnesium Infiltration to Predict Bitter Pit in Apples

Bitter pit (BP) is the main physiological disorder of apples in Chile. Its incidence affects pre- and postharvest handling of the fruit and the profitability of this species. Since 1991, its control and prediction have been studied by this research team through field and laboratory trials. The BP incidence is linked to the fruit Ca concentration; however, fruit Ca analysis has not adequately predicted BP incidence in postharvest. Several authors have proposed Ca/Mg antagonism, which has been the basis to develop a predictive method through fruit Mg infiltration (IMG) 40 days before harvest. IMG has been massively used for two seasons in Chile, with 375 samples processed in 1997 and 1170 in 1998. The industry has been increasing its proportion of the samples processed, from 22% in 1997 to 71% in 1998. The most prominent varieties are `Granny Smith' (GS) > `Braeburn' (BR) > `Royal Gala' (RG) > `Red King Oregon' (RKO). The massive use of IMG has obtained predictive capacities (r2 between BP predicted and BP after 3 months regular cold storage) of 0.8 for `Fuji'; 0.7 for GS, BR, and RG; and 0.58 for RKO. (This reduction in the predictive capacity with regards to the previous research under controlled conditions would, in part, be due to problems in obtaining fruit samples: non-uniform fruit size, inadequate sampling dates, diverse fruit numbers, etc.) Developments are underway to increase the geographical coverage of the service, the predictive capacity of the method for certain cultivars and productive areas and the number of samples processed.

Effects of Cobalt Gamma Radiation on San Jose Scale (Homoptera: Diaspididae) Survival on Apples in Cold and Controlled-Atmosphere Storage

‘Red Delicious’ apples ( Malus pumila (Mill.)) infested with San Jose scale, Quadraspidiotus perniciosus (Comstock), harvested from commercial and experimental orchards were subjected to cobalt-60 gamma radiation and then stored in either regular cold storage, controlled-atmosphere storage, or at room temperature. Scale survival measured at various intervals after treatment declined with time and the magnitude of the radiation dose received. Survival was not influenced by method of storage.

RESPONSE OF ‘TOP RED DELICIOUS’ APPLES TO DAMINOZIDE

ABSTRACTDaminozide was applied at 2.2, 4.5, 6.7 or 9.0 kg/ha to ‘Top Red Delicious’ apple trees 86 days after full bloom the first year and at 2.2, 3.4 or 4.5 kg/ha, 80 days after full bloom the second year. At commercial harvest, after 2 and 4 months regular cold storage, and after 6 and 10 months of controlled atmosphere (CA) storage apples were evaluated for carbon dioxide, ethylene production, flesh firmness, external color, soluble solids, acids, subjective appearance and daminozide residue. Ethylene production was reduced as daminozide application was increased. Delay in onset of the climacteric ranged from 3 to 21 days depending on chemical rate used. Firmness, red color, acids, subjective appearance and number of days to reach climacteric were significantly improved by all rates of daminozide. Quality differences due to daminozide were evident following both types of storage. Daminozide residues were directly related to rate and did not dissipate during storage. There was no detectable daminozide carry‐over in fruit from year to year.

EFFECTS OF PICKING DATE, DELAYED STORAGE, STORAGE TEMPERATURE, AND STORAGE ATMOSPHERE ON THE QUALITY OF STARRING DELICIOUS APPLES

The effects of picking date, storage atmosphere, storage temperature, and delayed storage on the behavior of Starking Delicious apples (Malus sylvestris Mill.) were studied over a 3-yr period. Regular cold storage, controlled atmosphere storages of 2% CO2 + 3% O2, and 0% CO3 + 3% O2, delayed storage of 48 h at 20 C prior to cold and controlled-atmosphere storage and temperatures of 0 and − 1 C were the treatments used. Temperature showed little or no effect on firmness, acidity, soluble solids, core browning, or flesh browning but controlled atmosphere treatments at − 1 C markedly reduced the incidence of scald compared with 0 C. Apples from the 2% CO2 + 3% O2 atmosphere had significantly more core browning than those from the 0% CO2 + 3% O2 atmosphere. The fruit picked later had less core browning than that picked 1 wk earlier when stored in the 2% CO2 + 3% O2 atmosphere. Fruit stored in a 2% CO2 + 3% O2 atmosphere was firmer than that in 0% CO2 + 3% O2.

Preharvest and Postharvest Applications of Benzimidazoles for Control of Storage Decay of Pears1

Abstract Two orchard sprays with 800 ppm methyl l-(butylcarbamoyl)-2-benzimidazole-carbamate (benomyl) or three orchard sprays with 300 ppm 2-(4-thiazolyl) benzimidazole (thiabendazole or TBZ) achieved significant control of storage decay of ‘Spadona’ pears (Pyrus communis L.). Almost complete control of storage decay required postharvest dip-treatments of 1000 ppm benomyl or 500 ppm TBZ. Penicillium expansum and Botrytis cinerea (Pers. ex Fr.) were inhibited by these treatments but Alternaria tenuis (Nees ex Cda.) was unaffected and its incidence increased during storage, possibly due to control of the other organisms. These benzimidazole treatments tended to increase the incidence of internal breakdown of treated pears during prolonged regular cold storage.