Submitted to: HortScience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 25, 2003
Publication Date: June 1, 2004
Citation: Luo, Y., Mcevoy, J.L., Wachtel, M.R., Kim, J., Huang, Y. 2003. Package film oxygen transmission rate affects postharvest biology and quality of fresh-cut cilantro leaves. American Society for Horticultural Science. HortScience Vol.39(3)June 2004, pg 567-570
Interpretive Summary: Cilantro, also known as Chinese parsley or coriander, is an important fresh culinary herb in the United States. As with other fresh culinary herbs, there is an increasing demand by consumers for a fresh-cut, pre-packaged product. However, fresh-cut cilantro has a relatively high respiration rate that decreases its potential shelf-life. We studied the effect of using various packaging films during cold storage that result in various internal atmospheres for controlling respiration and metabolism that shorten shelf-life. We found a superior film that was able to maintain a proper atmosphere essential for ensuring good quality, fresh-cut cilantro that limited growth of microorganisms and extended shelf-life for up to 14 days in cold storage. Further research is planned to examine the ability of foodborne pathogens under storage conditions used for preparing and marketing fresh-cut cilantro. This information will be important for the fresh produce industry for obtaining the desired shelf-life for packaged fresh-cut cilantro and for various food service institutions that use fresh-cut product in cafeterias, etc. Also, consumers will benefit by having a superior product available for purchase at grocery stores.
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 postharvest physiology and quality of the products. Package film OTR significantly (P<0.001) influenced the package atmospheres and the resultant postharvest physiology and quality of fresh-cut cilantro leaves during cold storage (0 degree C). Oxygen and carbon dioxide levels of the packages prepared with 3500 ml oxygen per day per square meter films reached equilibrium of 1.5-2.3% oxygen and 3.6-4.1% carbon dioxide on day 3 and maintained this level throughout the storage. The gas compositions of the packages of 6200 ml oxygen per day per square meter films showed a similar trend, except they equilibrated at a higher oxygen (3.6-5.6%) and lower carbon dioxide (2.7-3.3%) level. Fresh-cut cilantro leaves in both packages exhibited the highest membrane integrity as evidenced by the lowest membrane 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 oxygen per day per square meter film packages displayed a rapid depletion of oxygen and accumulation of carbon dioxide, with nearly no oxygen (appox. 0.02%) and high carbon dioxide (7.7-9.0%) levels inside the packages from day 6 until the end of storage. A rapid increase in membrane electrolyte leakage was observed on 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 rating at the end of storage ("dislike slightly"). Samples packaged in perforated bags lost moisture over time, and small numbers of wilted leaves were seen. There was a gradual increase in aerobic organisms over time with no significant difference among treatments. There was an increase in anaerobic microorganisms on cilantro leaves packaged in 1700 ml oxygen per day per square meter film, although only about 0.5 log cfu per gram difference was observed among the treatments and over time.