CNU Journal of Agricultural Science 40(2), 2013. 6 131 The effect of citrus and onion peel extracts, calcium lactate, and phosvitin on microbial quality of seasoned chicken breast meat Amali U. Alahakoon, Young Sik Bae, Hyun Joo Kim, Samooel Jung, Dinesh D. Jayasena, Hae In Yong, Sun Hyo Kim, Cheorun Jo* Department of Animal Science and Biotechnology, Chungnam National University, Daejeon 305-764, Republic of Korea Received on 11 April 2013, revised on 2 May 2013, accepted on 2 May 2013 Abstract : The inhibitory effect of citrus peel extract, onion peel extract, calcium lactate and phosvitin on microbial growth was investigated in seasoned chicken breast meat during aerobic storage at 4℃, 10℃ and 20℃. Citrus peel and onion peel extract significantly improved (p<0.05) the microbial quality of the sample by reducing the initial counts of the microbial flora compared to control and other two treatments. Data clearly revealed that the counts of the total aerobic bacteria significantly increased with the increase in storage temperature. The shelf life of all samples stored under 20℃ was less than 6 days, while the shelf life of citrus and onion treatment can be extended more than 9 days at 4℃ and more than 6 days at 10℃ in aerobic storage condition. These results indicated that citrus and onion peel extracts are efficient treatment methods to prevent microbial spoilage of seasoned chicken products during storage at 4℃. However, there was an adverse effect of addition of citrus and onion peel extract on several sensory attributes which need to be improved by reformulation of seasoning. Key words : Citrus peel extract, Onion peel extract, Calcium lactate, Phosvitin, Seasoned chicken *Corresponding author: Tel: +82-42-821-5774 E-mail address: cheorun@cnu.ac.kr I. Introduction The popularity of the ready-to-cook (RTC) and ready-to-eat (RTE) meat products is growing all over the world due to its convenience (Lee et al., 2005). However, microbial contamination of RTE and RTC meat products occurs during processing such as slicing, packaging, and other handling activities (Lin et al., 2006). It is important to store these products under frozen temperature to prevail the microbiological quality. However, freezing is a costly method together with some adverse effects on texture and consumer acceptance (Fallah et al., 2010). Even though the use of chemical preservatives can effectively prevent the growth of most foodborne microorganisms, there is a growing concern over safety problems related to chemical preservatives. Hence, searching for new types of effective and non-toxic natural antimicrobial compounds is essential (Chun-Lin et al., 2013). Citrus peel is a natural antimicrobial and antioxidant source rich in polyphenol compounds, mainly flavonoids including hesperidin, naringin, nobiletin, anthocyanins, and coumarins located in the cell vacuoles of the citrus peel albedo tissue (Elisa et al., 2013). Large quantity of citrus peel is generated as a by-product of juice industry in many countries (Bocco et al., 1998). In Korea, about 40,000 tons of citrus peel by-products out of 150,000 tons of citrus have been produced annually during citrus juice processing (Kang et al., 2006). Isolation of functional compounds such as dietary fiber from citrus peel can be of great interest to the food industry (Fernandez-Lopez et al., 2004). Citrus essential oils have been found to inhibit Gram-positive and Gram-negative bacteria as well as yeasts, molds and food poisoning bacteria (Chun-Lin et al., 2013). Furthermore, flavonoids present in citrus CNU Journal of Agricultural Science Vol. 40, No. 2, pp. 131-137, June 2013 DOI: http://dx.doi.org/10.7744/cnujas.2013.40.2.131