The Effect of Ziziphora clinopodioides Essential Oil and Nisin on Chemical and Microbial Characteristics of Fish Burger during Refrigerated Storage

Ziziphora clinopodioides is from the genus of Ziziphora and family of Lamiaceae,which grows in Iran and Turkey. This study was conducted to preserve the chemical and microbial quality of trout fish burger during storage using Ziziphora clinopodioides essential oil (ZEO) individually and in combination with nisin.  Firstly, the chemical composition of ZEO was determined using GC-MS analysis. Different treatments of trout fish burger were formulated using ZEO and nisin as natural preservatives, stored in refrigerator for 20 days and were analyzed for chemical (pH and Total Volatiles Base-Nitrogen (TVB-N)) and microbial (total viable count, psychotropic counts, Enterobacteriaceae count and Pseudomonas spp count) characteristics.at 5-day intervals.The Results indicated a yield of 1% (w/w) for ZEO isolation and Pulegone (40.09%), Menthone (13.76%) and Isomenthone (12.31%) were identified as the major components of phytochemicals of ZEO. According to the obtained results combination of ZEO and nisin had the strongest effect on chemical and microbial quality of fish burger; however, their individual use had significant effects on preserving the chemical and microbial quality of fish burger as well. based on results of this study, formulation of ZEO and Nisin in fish burger especially in combinations can prolong its shelf life and control chemical and microbial changes during storage at 4˚ C.