Assessment of radiation sensitivity of fresh-cut vegetables using electrolyte leakage measurement

ABSTRACT Fresh-cut cucumbers are popular worldwide, but they are prone to spoilage due to tissue damage caused by processing. The effects of controlled atmosphere storage (CAS) at 3% O2 and 7% CO2 or 8% O2 and 2% CO2 on microorganisms and the quality of fresh-cut cucumbers (Cucumis sativus L. cv. Chinese Long) at 4°C and 90% relative humidity were investigated in this study. The results showed that compared with the control group, both controlled atmosphere treatments maintained chlorophyll concentration, appearance, and color of fresh-cut cucumbers effectively; inhibited respiration rate and polyphenoloxidase (PPO) and peroxidase (POD) activity; delayed the decrease in firmness and the increase in relative electrolyte leakage; and inhibited the growth of microorganisms on cucumbers during storage. On day 10, the chlorophyll concentration and firmness of cucumbers stored at 3% O2 and 7% CO2 was 1.15 and 1.04 times that of cucumbers stored at 8% O2 and 2% CO2, respectively. Respiration rate, relative electrolyte leakage, polyphenoloxidase activity, peroxidase activity, and levels of total bacteria, coliforms, and Pseudomonas spp. at 3% O2 and 7% CO2 were 19.79, 6.01, 5.45, 88.50, 18.07, 16.14, and 19.76% lower than at 8% O2 and 2% CO2, respectively. In conclusion, storage at 3% O2 and 7% CO2 was effective in inhibiting microorganisms and maintaining the quality of stored fresh-cut cucumbers. HIGHLIGHTS

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Package Atmosphere Affects Postharvest Biology and Quality of Fresh-cut Cilantro Leaves

HortScience ◽

10.21273/hortsci.39.3.567 ◽

2004 ◽

Vol 39 (3) ◽

pp. 567-570 ◽

Cited By ~ 34

Author(s):

Yaguang Luo ◽

James L. McEvoy ◽

Marian R. Wachtel ◽

Ji Gang Kim ◽

Yun Huang

Keyword(s):

Electrolyte Leakage ◽

Transmission Rate ◽

Storage Period ◽

Visual Quality ◽

Storage Condition ◽

Modified Atmosphere ◽

Oxygen Transmission Rate ◽

Fresh Cut ◽

Over Time

Experiments were conducted to develop a modified atmosphere packaging system for fresh-cut cilantro (Coriandrum sativum L.) leaves, and to determine the effect of package film oxygen transmission rate (OTR) on package atmosphere and the consequence on quality and microbiology of the product. Package film OTR significantly (P < 0.001) influenced the package atmospheres and the resultant postharvest physiology and quality of fresh-cut cilantro leaves under the tested package configuration (bag size 19 × 22 cm, product fill weight 85 g/bag) and storage condition (0 °C). Oxygen and carbon dioxide levels of the packages prepared with 3500 mL·d-1·m-2 OTR films equilibrated at 1.5 to 2.3 kPa and 3.6 to 4.1 kPa, respectively, on day 3 and maintained this level throughout the storage. The gas compositions of the packages with 6200 mL·d-1·m-2 OTR films showed a similar trend, except they equilibrated at a higher O2 (3.6 to 5.6 kPa) and lower CO2 (2.7 to 3.3 kPa) level. Fresh-cut cilantro leaves in both packages exhibited the highest tissue integrity as evidenced by the lowest tissue electrolyte leakage, with high overall visual quality scores (like moderately to like very much) at the end of 14 days storage. However, atmospheres in 1700 mL·d-1·m-2 OTR film packages displayed a rapid depletion of O2 and accumulation of CO2, with essentially no O2 (≈0.02 kPa) and high CO2 (7.7 to 9.0 kPa) levels inside the packages from day 6 until the end of storage. A rapid increase in tissue electrolyte leakage was observed in cilantro leaves in these packages starting on day 6, increasing 6-fold at the end of the storage period. Products in these packages developed a strong off-odor, accompanied by a rapid loss of typical aroma and overall visual quality, with an unacceptable quality rating at the end of storage (dislike slightly). Samples packaged in perforated bags (without modified atmosphere) lost moisture over time, and small numbers of wilted leaves were seen. There was a slow but significant (P < 0.001) increase in aerobic organisms over time with no significant (P > 0.05) difference among treatments. There was an increase in anaerobic microorganisms on cilantro leaves packaged in 1700 mL·d-1·m-2 OTR film, although only ≈0.5 log cfu/g difference was observed among the treatments and over time.

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Processing Line Effects on Storage Attributes of Fresh-cut Spinach Leaves

HortScience ◽

10.21273/hortsci.35.7.1308 ◽

2000 ◽

Vol 35 (7) ◽

pp. 1308-1311 ◽

Cited By ~ 11

Author(s):

D. Mark Hodges ◽

Charles F. Forney ◽

Wendy Wismer

Keyword(s):

Lipid Peroxidation ◽

Electrolyte Leakage ◽

Spinacia Oleracea ◽

Chlorophyll B ◽

Storage Quality ◽

Processing Line ◽

Hue Angle ◽

Fresh Cut ◽

Spinach Leaves

The degree of damage that may occur through harvesting and packing represents one of the major factors that can affect quality of fresh-cut produce. The purpose of this study was to examine the effects of different steps in a representative fresh-cut processing line on storage quality of spinach (Spinacia oleracea L.). To this end, spinach leaves were removed at successive points on the line: 1) before entry into the line (control); 2) after a shaking procedure but before initial rinsing with 10 °C water + 5 mg·L-1 chlorine dioxide; 3) after centrifugal drying; and 4) after commercial packaging. After removal from the different points in the line, the spinach samples were stored at 10 °C for 16 days, during which time malondialdehyde (MDA) concentration (lipid peroxidation assay), electrolyte leakage (membrane leakiness), chlorophyll content (a, b, and total), and color attributes (L, saturation, hue angle) were measured. Both lipid peroxidation and electrolyte leakage increased with time of storage and with stage of procesing. Electrolyte leakage increased most in material removed after the shaking procedure, but prior to hydrocooling. Overall total chlorophyll loss during storage did not change with time of removal from the processing line, although overall chlorophyll b content decreased in stored material 8 days following centrifugal drying and packaging. A more rapid loss in chlorophyll a relative to chlorophyll b over the first 8 days of storage was reflected in hue angle measurements regardless of the point of removal. The processing line under study, thus had both beneficial and detrimental effects on storage quality of spinach. Detrimental effects associated with centrifugal drying and packaging procedures could be modified to improve quality.

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358 Quality of Fresh-cut Onions

HortScience ◽

10.21273/hortsci.34.3.505b ◽

1999 ◽

Vol 34 (3) ◽

pp. 505B-505

Author(s):

M. Khatoon ◽

A. Hakim

Keyword(s):

Weight Loss ◽

Electrolyte Leakage ◽

Controlled Atmosphere ◽

Fungus Infection ◽

Ethanol Content ◽

Quality Retention ◽

Fresh Cut ◽

Atmosphere Storage ◽

Better Than

Sweet onions (Allium cepae) were diced or sliced, ringed with sodium hypochloride solution (50 ppm) for about 2 min, and drained. After that, they were packaged in perforated polyethylene package and stored in an air and controlled-atmosphere (2% O2 and 5% CO2) room at 1 °C for 5 and 10 days. Weight loss, fungus infection, surface discoloration, flavor and taste, ethanol content, TSS, pH, firmness, and electrolyte leakage were determined after storage. Based on weight loss, fungus infection, surface discoloration, flavor and taste, ethanol content, TSS, pH, firmness, and electrolyte leakage, controlled-atmosphere storage, onions diced exhibited better quality retention than those that were stored in air. The overall quality of discs was better than slices. Onion stored for 10 days showed higher weight loss, more fungus infection and surface discoloration, off-flavor, bad taste, higher ethanol content, lower TSS content, less firm and higher electrolyte leakage than those stored for 5 days. So, the quality of fresh-cut onion disks can be maintained properly in a controlled atmosphere with reduced oxygen and elevated carbon dioxide up to 10 days.

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Comparison of Generally Recognized as Safe Organic Acids for Disinfecting Fresh-cut Lettuce

10.1101/348045 ◽

2018 ◽

Author(s):

Jiayi Wang ◽

Dongbing Tao ◽

Yubo Liu ◽

Siwen Han ◽

Fenge Zheng ◽

...

Keyword(s):

Lactic Acid ◽

Organic Acids ◽

Electrolyte Leakage ◽

Sensory Quality ◽

Fresh Produce ◽

Microbial Reduction ◽

Cold Chain ◽

Minimal Processing ◽

Log Reduction ◽

Fresh Cut

ABSTRACTIn this study, we aimed to determine the organic acids (acetic, lactic, citric, malic, propionic, succinic, and tartaric acids; 1% and 0.5%, w/w or v/v) that were most effective for fresh-cut lettuce disinfection based on analysis of quality (i.e., color, electrolyte leakage, and sensory quality) and microbial examination. The results showed that these acids did not negatively affect the color quality (i.e., L*, a*, b*, whiteness index, and sensory color). Additionally, 0.5% lactic acid led to the lowest electrolyte leakage (0.83%), which was not significantly different (p > 0.05) from that of distilled water (0.46%). Lactic acid (1%) did not affect the sensory quality and led to the highest microbial reduction (1.45 log reduction in aerobic plate counts [APCs]; 2.31 log reduction in molds and yeasts [M&Y]) and was therefore recommended as the primary choice for lettuce disinfection. Malic acid (0.5%), with a 1.07% electrolyte leakage rate, 0.73 log reduction in APCs, and 1.40 log reduction in M&Y, was better than the other six acids (0.5%) and was recommended as a pH regulator and a potential synergistic agent for oxidizing sanitizers. Acetic acid (1%) negatively affected the sensory quality and led to the highest electrolyte leakage (2.90%). Microbial analysis showed that propionic acid (0.5% and 1%) was ineffective for disinfection of lettuce (p > 0.05); thus, acetic and propionic acids were not recommended. Our results provide insights into the choice of sanitizers and formula design in food safety.IMPORTANCESince chlorine is forbidden in several countries, generally recognized as safe organic acids are used in minimal processing industries and in household sanitizers. The disinfection efficacy of organic acids has been studied when used alone or with oxidizing sanitizers. However, since different antibacterial mechanisms, contact time, fresh produce, and concentration have been reported, the acids most effective for single fresh produce disinfection, especially that of lettuce, an important salad vegetable, are not known. Moreover, in developing countries, because of imperfections in field management, cold chain transportation, and minimal processing industry development, the demand for low-cost household sanitizers is greater than that for minimally processed fresh produce. In this work, microbial load in lettuce was determined after disinfecting with seven GRAS organic acids. The changes in quality were also determined. These results provide insights into the choice of minimal processing sanitizers and a formula design for household sanitizers.

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Tomato Cultivation Systems Affect Subsequent Quality of Fresh-cut Fruit Slices

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.125.6.729 ◽

2000 ◽

Vol 125 (6) ◽

pp. 729-735 ◽

Cited By ~ 19

Author(s):

Ji Heun Hong ◽

Douglas J. Mills ◽

C. Benjamin Coffman ◽

James D. Anderson ◽

Mary J. Camp ◽

...

Keyword(s):

Electrolyte Leakage ◽

Chilling Injury ◽

Titratable Acidity ◽

Soluble Solids ◽

Forecasting Model ◽

Disease Forecasting ◽

Hairy Vetch ◽

Fresh Cut ◽

Polyethylene Mulch

Experiments were conducted to compare changes in quality of slices of red tomato (Lycopersicon esculentum Mill. `Sunbeam') fruit from plants grown using black polyethylene or hairy vetch mulches under various foliar disease management systems including: no fungicide applications (NF), a disease forecasting model (Tom-Cast), and weekly fungicide applications (WF), during storage at 5 °C under a modified atmosphere. Slices were analyzed for firmness, soluble solids content (SSC), titratable acidity (TA), pH, electrolyte leakage, fungi, yeasts, and chilling injury. With both NF and Tom-Cast fungicide treatments, slices from tomatoes grown with hairy vetch (Vicia villosa Roth) mulch were firmer than those from tomatoes grown with black polyethylene mulch after 12 days storage. Ethylene production of slices from fruit grown using hairy vetch mulch under Tom-Cast was ≈1.5- and 5-fold higher than that of slices from WF and NF fungicide treatments after 12 days, respectively. The percentage of water-soaked areas (chilling injury) for slices from tomatoes grown using black polyethylene mulch under NF was over 7-fold that of slices from tomatoes grown using hairy vetch under Tom-Cast. When stored at 20 °C, slices from light-red tomatoes grown with black polyethylene or hairy vetch mulches both showed a rapid increase in electrolyte leakage beginning 6 hours after slicing. However, slices from tomatoes grown using the hairy vetch mulch tended to have lower electrolyte leakage than those grown with black polyethylene mulch. These results suggest that tomatoes from plants grown using hairy vetch mulch may be more suitable for fresh-cut slices than those grown using black polyethylene mulch. Also, use of the disease forecasting model Tom-Cast, which can result in lower fungicide application than is currently used commercially, resulted in high quality fruit for fresh-cut processing.

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Heritability of Fresh-cut Fruit Quality Attributes in Capsicum

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.141.4.308 ◽

2016 ◽

Vol 141 (4) ◽

pp. 308-314 ◽

Cited By ~ 1

Author(s):

John R. Stommel ◽

Mary J. Camp ◽

Judith M. Dumm ◽

Kathleen G. Haynes ◽

Yaguang Luo ◽

...

Keyword(s):

Weight Loss ◽

Electrolyte Leakage ◽

Transmission Rate ◽

Fruit Weight ◽

Oxygen Transmission Rate ◽

Partial Pressures ◽

Class 1 ◽

Cut Quality ◽

Fresh Cut ◽

Current Report

Fresh pepper (Capsicum) fruit that are sliced and/or diced are referred to as fresh-cut products. The current report evaluates the inheritance of postharvest attributes that contribute to pepper fresh-cut quality. Marketable green fruit of large-fruited Capsicum annuum accessions with bell and related pod types (Class 1), C. annuum accessions with jalapeno and serrano pod types (Class 2), and thin-walled “aji”-like tabasco pod types from Capsicum baccatum, Capsicum frutescens, and Capsicum chinense (Class 3) were processed and stored up to 14 days in selective oxygen transmission rate packaging. Fresh-cut attributes were influenced by genotype as well as year. For all pod types, O2 and CO2 partial pressures in storage packages, tissue weight loss, and electrolyte leakage differed among accessions, days of storage, and years of testing. Percent O2 declined and CO2 and electrolyte leakage generally increased during storage. Some accessions in Class 1 and Class 2 maintained acceptable product quality during storage. Changes in fruit weight loss were small with greater weight loss observed in Class 1 accessions relative to weight loss for Class 2 and Class 3. Broad-sense heritability for fresh-cut attributes was moderate to low indicating that it will be difficult to breed for fresh-cut quality.

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Delayed Modified Atmosphere Packaging of Fresh-cut Romaine Lettuce: Effects on Quality Maintenance and Shelf-life

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.130.1.116 ◽

2005 ◽

Vol 130 (1) ◽

pp. 116-123 ◽

Cited By ~ 34

Author(s):

Ji Gang Kim ◽

Yaguang Luo ◽

Robert A. Saftner ◽

Kenneth C. Gross

Keyword(s):

Electrolyte Leakage ◽

Modified Atmosphere Packaging ◽

Ambient Air ◽

Modified Atmosphere ◽

Romaine Lettuce ◽

Quality Maintenance ◽

Oxygen Transmission Rate ◽

Fresh Cut ◽

Volatile Production

Fresh-cut tissues are subjected to severe injury during preparation that leads to increased respiratory activity and quality deterioration. Modified atmosphere packaging (MAP) has been used to maintain quality of fresh-cut produce, but O2 depletion and excessive CO2 accumulation can be injurious. This study was conducted to evaluate the effect of delayed packaging and MAP using two different oxygen transmission rate (OTR) films on quality maintenance and shelf stability of fresh-cut romaine lettuce (Lactuca sativa L.). Romaine lettuce leaves were cut, washed, dried, and placed for 0, 4, 8, and 12 hours at 5 °C in ambient air before packaging. Fresh-cut samples were placed into packages prepared from films having OTRs of 8.0 and 16.6 pmol·s-1·m-2·Pa-1, flushed with N2 to reach an initial headspace O2 level of 1.5 kPa O2, and stored at 5 °C for up to 14 days. Delayed packaging affected gas composition, fermentative volatile production, off-odor development, color, CO2 injury, and tissue electrolyte leakage. With increasing delay before packaging, fermentative volatile production, off-odor development, and CO2 injury progressively decreased and discoloration increased. The modified atmospheres obtained with 16.6 OTR film increased discoloration when present, and generally had less off-odor development and CO2 injury compared to MAP with 8.0 OTR film. Delayed packaging affected overall quality of fresh-cut romaine lettuce packaged with both films. A 12-hour delayed packaging into packages prepared from 8.0 OTR film maintained quality by inhibiting CO2 injury, off-odor development, and tissue electrolyte leakage. However, an 8-hour delayed packaging into packages prepared from 16.6 OTR film was better at maintaining the quality of fresh-cut romaine lettuce at 5 °C for 14 days. The results indicated that delayed packaging could be an alternative method to optimize or balance package O2 during suboptimal OTR film packaging conditions.

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1-Methylcyclopropene (1-MCP) for Maintaining Texture Quality of Fresh-cut Tomato

HortScience ◽

10.21273/hortsci.39.6.1359 ◽

2004 ◽

Vol 39 (6) ◽

pp. 1359-1362 ◽

Cited By ~ 28

Author(s):

Jiwon Jeong ◽

Jeffrey K. Brecht ◽

Donald J. Huber ◽

Steven A. Sargent

Keyword(s):

Lycopersicon Esculentum ◽

Developmental Stage ◽

Ethylene Production ◽

Electrolyte Leakage ◽

Chilling Injury ◽

Fresh Cut ◽

Textural Changes ◽

The Relationship

A study was conducted to determine the effect of 1-methylcyclopropene (1-MCP) on textural changes in fresh-cut tomato (Lycopersicon esculentum, Mill.) slices during storage at 5 °C. The relationship between fruit developmental stage and tissue watersoaking development was also determined. Fresh-cut tomato slices prepared from light-red fruit that had been exposed to 1-MCP (1 μL·L-1 for 24 h at 5 °C) retained significantly higher pericarp firmness during storage at 5 °C for 10 d than slices from nontreated fruit or slices stored at 10 or 15 °C and they also had a significantly higher ethylene production maximum. 1-MCP (1 or 10 μL·L-1 for 24 h at 5 °C) had no affect on the firmness of fresh-cut, red tomato slices at 5 °C or on slices prepared from 5 °C-stored, intact red tomatoes. Nor did 1-MCP treatment have a significant effect on electrolyte leakage of tomato slices or intact fruit stored at 5 °C. Slices from fruit of the same developmental stage but with higher initial firmness values had less watersoaking development and responded better to 1-MCP treatment during 8 d storage at 5 °C. 1-MCP (1 μL·L-1) was more effective in reducing watersoaking in light red stage tomato slices when applied at 5 °C for 24 h compared with 1-MCP applied at 10 or 15 °C. Watersoaking development was also more rapid in fresh-cut tomato slices as initial fruit ripeness advanced from breaker to red stage. Our results suggest that watersoaking development in fresh-cut tomato slices is an ethylene-mediated symptom of senescence and not a symptom of chilling injury as had previously been proposed.

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412 Quality of Packaged Fresh-cut Cantaloupe

HortScience ◽

10.21273/hortsci.34.3.515a ◽

1999 ◽

Vol 34 (3) ◽

pp. 515A-515

Author(s):

A. Hakim ◽

A. Purvis ◽

M. Khatoon

Keyword(s):

Weight Loss ◽

Electrolyte Leakage ◽

Storage Time ◽

Controlled Atmosphere ◽

Fungus Infection ◽

Lower Weight ◽

Lycopene Content ◽

Fresh Cut ◽

Sodium Hypochloride

Cantaloupe at commercial stage of maturity were sliced, i.e., prepared as minimally proceed, rinsed with or without sodium hypochloride solution (50 ppm), and drained. They were stored in perforated polyethylene package (PE) at 1 °C in air and controlled atmosphere (2 % O2 and 5 % CO2) for 5 and 10 days. Fresh-cut cantaloupe slices were analyzed initially and after 5 and 10 days of storage for weight loss, lycopene content, fungus infection, flavor and taste, TSS, pH, ethanol, firmness, and electrolyte leakage. Fruit stored in CA exhibited lower weight loss, higher lycopene content, less fungus infection, better flavor and taste, more firmness, higher TSS content, and lower electrolyte leakage than store in air. When compared to fruit treated with sodium hypochloride, lower lycopene content, higher fungus infection, inferior flavor and taste, more softness, and higher electrolyte leakage were detected in fruit that were not rinsed with sodium hypochloride solution. Extended storage time resulted in higher weight loss, increased fungus infection, bad taste, off-flavor, more softness, lower TSS content, and higher leakage value. This study indicates that it is possible to extend the shelf-life of fresh-cut cantaloupe slices from 5 to 10 days if kept at 1 °C in 2% O2 and 5% CO2 in PE package.

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