ORIGINAL ARTICLE Effects of chitosan coating containing lysozyme or natamycin on shelf-life, microbial quality, and sensory properties of Halloumi cheese brined in normal and reduced salt solutions Ghadeer F. Mehyar 1 | Anas A. Al Nabulsi 2 | Mohammed Saleh 1 | Amin N. Olaimat 3 | Richard A. Holley 4 1 Department of Nutrition and Food Technology, The University of Jordan, Amman, 11942, Jordan 2 Department of Nutrition and Food Technology, Faculty of Agriculture, Jordan University of Science and Technology, Irbid, Jordan 3 Department of Clinical Nutrition and Dietetics, Hashemite University, Zarqa, 13133, Jordan 4 Department of Food Science, University of Manitoba, Winnipeg, MB R3T 2N2, Canada Correspondence Ghadeer F. Mehyar, Department of Nutrition and Food Technology, The University of Jordan, Amman, 11942, Jordan. Email: g.mehyar@ju.edu.jo Funding information University of Jordan (Deanship of Research and Graduate Studies) Abstract The effects of chitosan (C) coating with or without lysozyme (L) or natamycin (N) on shelf-life, microbial quality, and sensory properties of Halloumi cheese held at 3 8C or 25 8C in 5%, 10% or 15% (w/v) NaCl were examined. Coatings increased cheese shelf-life by  5 days than the control when brined in 5% and 10% NaCl at 3 8C but did not affect the shelf-life of cheese in 15% NaCl. Nonetheless, coatings reduced psychrotrophs, anaerobes, lactic acid bacteria, and yeasts and molds by 1.8 to 2.2 log in 15% brined cheese. Reductions of microbial species contaminating Hal- loumi cheese at 10% and 15% brine were not significantly different with CL and CN coatings throughout storage at 3 8C. Coatings did not adversely affect sensory properties of cheese. There- fore, brine concentration could be reduced to 10% for CL and CN-coated cheeses. Practical applications Results support the possibility of reducing the high salt concentration in brine solution of Halloumi cheese by using a chitosan coating containing lysozyme or natamyc in which provided similar shelf-life and microbial stability. The coatings did not adversely affect the sensory properties of cheese and can be applied by a simple step during processing which facilitates their use in the food industry. 1 | INTRODUCTION Halloumi cheese, a semi-hard to hard white brined cheese, is extremely popular in the Middle East and the Mediterranean region. During proc- essing, Halloumi cheese is boiled in salt solution which eliminates most of the contaminating microorganisms, except thermoduric bacteria including some species of lactic acid bacteria (LAB). The metabolic activ- ity of LAB may increase the internal acidity of cheese and thus contrib- ute to the development of desired flavor as well as limit the growth of other species (Bintsis & Papademas, 2002; Kaminarides, Stamou, & Massouras, 2007; Kamleh, Toufeili, Ajib, Kanso, & Haddad, 2012). Under normal processing conditions, vacuum packaged Halloumi cheese has a shelf life of 3–7 days at 20–25 8C or 40–80 days at 4–5 8C (Kam- leh et al., 2012; Papademas & Robinson, 1998). However, microbial contamination of cheese surfaces during processing by handling and from food contact surfaces are considered the main reasons for early shelf-life termination of Halloumi cheese (Papademas & Robinson, 2000; Somers, Johnson, & Wong, 2001). A variety of microbial species has been isolated from Halloumi cheese including thermophilic spore forming anaerobes such as Bacillus and Clostridium, facultative microor- ganisms such as LAB (Lactobacillus spp. and Enterococcus faecium) and foodborne pathogens such as Listeria monocytogenes. Yeasts such as Candida species, Pichia membranifaciens and Debaromyces hansenii were also isolated at 2.3–2.8 3 10 5 cfu/g from Halloumi cheese or its brine solutions (Bintsis & Papademas, 2002; Papademas & Robinson, 2000). Processing of Halloumi cheese involves a brining step in which cheese is placed in 14–16% aqueous NaCl solution for 18 hr before being vacuum packaged. During this step, salt penetrates the cheese matrix which limits microbial growth and provides desirable flavor. However, the high salt content could have adverse effects on con- sumer health (Papademas & Robinson, 1998). Substituting NaCl with KCl in a 16% brine solution of Halloumi cheese did not affect LAB numbers, whereas use of lower salt concentrations ( 12%) in brine allowed heterogeneous spoilage microorganisms to grow (Ayyash & J Food Process Preserv. 2017;e13324. https://doi.org/10.1111/jfpp.13324 wileyonlinelibrary.com/journal/jfpp V C 2017 Wiley Periodicals, Inc. | 1 of 9 Received: 8 September 2016 | Revised: 31 January 2017 | Accepted: 31 January 2017 DOI: 10.1111/jfpp.13324