|Luo, Yaguang - Sunny|
Submitted to: Food Research International
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/22/2004
Publication Date: 9/28/2004
Citation: Wang, H., Feng, H., Luo, Y. 2004. Microbial reduction and storage quality of fresh-cut cilantro washed with acidic electrolyzed water and aqueous ozone. Food Research International. 37:949-956. Interpretive Summary: Cilantro is a low-growing vegetable item, and can be easily contaminated with pathogenic and spoilage microorganisms. Technology to decontaminate cilantro without losing quality has not been successful due to its perishable nature. As such, cilantro has been implicated in several food-borne illness outbreaks. This study explored the possibility of a combination treatment of acidified electrolyzed water (AEW) and aqueous ozone on microbial reduction and quality maintenance of fresh-cut cilantro during storage. Results indicated that a sequential treatment of cilantro with ozone and AEW significantly improved the effectiveness of microbial reduction from cilantro. This treatment also maintained a low growth rate of total aerobic bacteria and coliforms during cold storage. This information is of importance to future development of effective sanitizers to reduce microbial populations and maintaining food quality and safety of fresh produce. Thus, the research results will benefit the fresh produce industry.
Technical Abstract: Efficacy of decontamination treatments in reducing microbial populations on cilantro and in improving its storage quality was investigated. Fresh-cut cilantro was washed for 5 min, using tap water, acidic electrolyzed water (AEW) (pH 2.45, oxidation reduction potential 1130mV, and available chlorine 16.8 mg/L), aqueous ozone (3.9 mg/L), and chlorinated water (NaClO) (pH 6.5, available chlorine 50 mg/L), respectively, or washed with aqueous ozone for 5 min followed by AEW wash for another 5 min. Treated cilantro was packaged in 19×22 cm polyethylene bags prepared with the film of selected oxygen transmission rate of 6200 mL d-1 100 in-2) and stored at 0 °C for 14 days. The total microbial population, coliforms, electrolyte leakage and sensory qualities were examined every 4 days. Test results indicated that sequential wash of aqueous ozone followed by AEW achieved the highest initial microbial reduction. This treatment also maintained a lower growth rate of total aerobic bacteria and coliforms than the rest of the treatments. However, the higher electrolyte leakage observed in this treatment may also indicate cilantro tissue damage by this treatment. Using AEW alone also resulted in a moderate control of aerobic bacterial growth during storage. Ozone treatment, on the other hand, achieved the highest overall quality of cilantro during 14 days storage and also maintained the typical aroma of cilantro leaves.