Effect of initial oxygen concentration and film oxygen transmission rate on the quality of fresh-cut romaine lettuce

The objective of this study was to evaluate the influence of packaging films on the quality of canola oil which contains high concentration of fat under photooxidation condition and get the oxidation kinetics based on measuring the oxidation intensities including peroxide value, hexanal, and photosensitizer (chlorophyll). The canola oil was packaged by PET/CPP; KPET/PE was used for experiments. The change of light and oxygen transmission rate (OTR) of PET/CPP which was considered as the typical fatty foods packaging film under different light intensities was also tested. The results show that the peroxide value increased rapidly under light conditions and fitted the zero order kinetics; also the oxygen transmission rate had great impact on it; hexanal fitted the zero order kinetic in oil whose package of low OTR generated a lot; however package in high OTR films changed very slowly that might be dependent on the performance of hexanal through plastic films. The degradation of chlorophyll fitted the first order kinetic and decreased quickly under light but was almost independent of OTR of transparent packaging material. Light reduced the oxygen barrier properties of the films, which should be considered as the photooxidation condition (and the photooxidation condition thus should be considered).

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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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362 Prolonging the Shelf-life of Fresh-cut Tomato Slices through Modified Atmosphere and Low Temperature

HortScience ◽

10.21273/hortsci.34.3.506a ◽

1999 ◽

Vol 34 (3) ◽

pp. 506A-506

Author(s):

Ji Heun Hong ◽

Ken Gross

Keyword(s):

Relative Humidity ◽

Shelf Life ◽

Transmission Rate ◽

Chilling Injury ◽

Fungal Growth ◽

Atmospheric Composition ◽

Modified Atmosphere ◽

Oxygen Transmission Rate ◽

Fresh Cut ◽

Oxygen Transmission

Fresh-cut produce continues to be a rapidly growing industry. However, there is little information available on storage conditions for many commodities, particularly for fresh-cut tomato slices. A major problem with fresh-cut tomato slices is their short shelf-life. The best method to extend shelf-life is refrigerated storage, preferably around 4 to 5 °C. Unfortunately, tomato tissue is susceptible to chilling injury at such temperatures. Experiments were conducted to compare changes in quality of slices from red tomato (Lycopersicon esculentum Mill.) fruit during storage at 5 or 10 °C under various modified-atmosphere conditions. In this study, we used the fourth uniform slice from the stem end and analyzed for various quality attributes during the storage period. At both 5 and 10 °C storage temperatures, ethylene concentration in containers sealed with Film A (oxygen transmission rate of 60.3 or 77.9 ml per hour per m2 at 1 atm and 99% relative humidity at 5 or 10 °C, respectively) was higher than that sealed with Film B (oxygen transmission rate of 87.4 or 119.4 ml per hour per m2 at 1 atm and 99% relative humidity at 5 or 10 °C, respectively), during storage. In addition, chilling injury, as measured by percent of slices showing some water soaked-areas, in containers sealed with Film B was higher than that of slices in containers sealed with Film A. The percent of visible fungal growth of slices was roughly correlated with the degree of chilling injury, as measured by the percent of slices showing some water soaked-areas. After 13 days of storage at 5 °C, slices stored in containers with a beginning atmospheric composition of 12% CO2 /1% O2 were firmer, compared to slices given the other treatments. After 9 days of storage at 10 °C, no visible fungal growth was observed on slices in containers with a beginning atmospheric composition of 12% CO2/1% O2 or 12% CO2/20% O2. However, slices in containers with a beginning atmospheric composition of air, or 4% CO2/1 or 20% O2 and 8% CO2/1 or 20% O2 did show visible signs of fungal growth at 25%, 33%, 46%, 29%, and 100% of infected slices, respectively. Slices in containers given all treatments, with the exception of 12% CO2/1% O2, had visible fungal growth after 15 days of storage at 5 °C. Slices in containers containing eight slices had less chilling injury and visible fungal growth than those containing four slices. Chilling injury of slices stored in completely enclosed plastic containers, similar to those commonly observed in grocery food stores, was over 7-fold higher than chilling injury observed in slices containers covered with Film A after 12 days of storage at 5 °C. However, there were no significant differences in the amounts of the volatiles we measured, i.e., ethanol, ethyl acetate, hexanol and hexanal, between the two container types. These results suggested that modified-atmosphere packaging storage can extend shelflife, as well as inhibit chilling injury in fresh-cut tomato slices.

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Evaluation of the Storage Characteristics in Maintaining the Overall Quality of Whole and Fresh-Cut Romaine Lettuce during MA Storage

Horticulturae ◽

10.3390/horticulturae7110461 ◽

2021 ◽

Vol 7 (11) ◽

pp. 461

Author(s):

In-Lee Choi ◽

Joo-Hwan Lee ◽

Dam-Hee Choi ◽

Li-Xia Wang ◽

Ho-Min Kang

Keyword(s):

Loss Rate ◽

Transmission Rate ◽

Co2 Concentration ◽

Fresh Weight ◽

Romaine Lettuce ◽

Weight Loss Rate ◽

Factors Affecting ◽

Fresh Cut ◽

Storage Characteristics

This study aimed to examine the effect of modified atmosphere (MA) storage on the quality and storability of romaine lettuce. Whole and fresh-cut romaine lettuce were packaged with 1300; 10,000; 50,000; 100,000 cc m−2·day−1·atm−1 O2 transmission rate (OTR) films and stored at 2 or 8 °C for 15 days. The respiration and ethylene production rates before pre-cooling were higher in fresh-cut lettuce than in whole romaine lettuce. The reduction in fresh weight for whole and fresh-cut romaine lettuce during storage was less than 0.5%. The CO2 concentration was less than 2%, except for the 1300 cc treatment (at 8 °C for whole and fresh-cut lettuce) and 10,000 cc (in fresh-cut lettuce). At the end date of storage, the overall quality of the whole lettuce was good, the off-odor was lower in the 10,000 cc treatment, and the 50,000 cc treatment at 8 °C led to good overall quality in the fresh-cut lettuce. The chlorophyll content of the whole lettuce was maintained at a higher level in the treatment of 10,000 cc at 8 °C, while it was higher in the 50,000 cc treatments at 2 and 8 °C in the fresh-cut lettuce. Correlation and PCA confirmed that the main factors affecting the storability and quality of romaine lettuce were fresh weight loss rate, off-odor, and the concentration of CO2. In addition, the storage characteristics of whole and fresh-cut lettuce were opposite to 0 in PC1 and PC2, indicating that the storage characteristics were different depending on the processing type.

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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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(50) Effect of Delayed MA Packaging and Packaging Film on Quality Maintenance of Fresh-cut Iceberg Lettuce

HortScience ◽

10.21273/hortsci.40.4.1087e ◽

2005 ◽

Vol 40 (4) ◽

pp. 1087E-1088

Author(s):

Ji Gang Kim ◽

Sun Tay Choi ◽

Chai Il Lim

Keyword(s):

Transmission Rate ◽

Quality Maintenance ◽

Oxygen Transmission Rate ◽

Air Atmosphere ◽

Iceberg Lettuce ◽

Ma Packaging ◽

Fresh Cut ◽

Volatile Production ◽

Delayed Time

Modified atmosphere (MA) packaging has been used to maintain quality of fresh-cut lettuce, but O2 depletion and excessive CO2 accumulation can be injurious. This study was conducted to evaluate the effect of delayed MA packaging using three different films on quality maintenance of fresh-cut iceberg lettuce. Iceberg lettuce leaves were sliced, washed, dried, and placed for 0, 5, 10, and 15 hours under air atmosphere at 5 °C. Samples were packaged with 2.9 and 16.6 pmol·kg·Pa·s, oxygen transmission rate (OTR) films and microperforated film (P-plus), and stored for 12 days at 5 °C. Results indicated that delayed packaging affected gas composition (O2 and CO2), fermentative volatile production, off-odor, color, and tissue electrolyte leakage. With 2.9 OTR film, longer delayed time maintained quality by inhibiting off-odor development and the accumulation of ethanol. However, delayed packaging was not effective in maintaining quality of samples packaged with 16.6 OTR film and P-plus film. Regardless of delayed time, all 16.6 OTR-packaged samples had severe discoloration after 7 days of storage. All delayed treatments packaged with P-plus film attained the desired O2 (3–5 kPa) and CO2 levels (10–12 kPa) from day 9 to the end of storage. A 15-hour delayed packaging into packages prepared from 2.9 OTR film and samples packaged with P-plus film maintained quality by inhibiting off-odor development. The results indicate that delayed packaging could be an alternative method when fresh-cut lettuce is packaged with low OTR films.

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