بررسي اثر هم افزايي عصاره هاي آويشن دنايي و چاي سبز بر ويژگي هاي شيميايي و ميكروبي گوشت ماهي قزل آلاي رنگين كمان منجمد

The Synergistic Effects of Thymus daenensis and Camellia sinensis Hydroalcoholic Extracts on Chemical and Microbial Properties of Frozen Rainbow Trout

ﮔﻮﺷﺖ ﻣﺎﻫﯽ ﯾﮑﯽ از ﻣﻬﻢﺗﺮﯾﻦ ﻣﻨﺎﺑﻊ ﭘﺮوﺗﺌﯿﻨﯽ اﺳﺖ ﮐﻪ ﺳﺮﯾﻌﺎً دﭼﺎر ﻓﺴﺎد ﺧﻮاﻫﺪ ﺷﺪ. ﻟﺬا ﻫﺪف از اﯾﻦ ﻣﻄﺎﻟﻌﻪ ﺑﺮرﺳﯽ اﺛﺮ ﻫﻢ اﻓﺰاﯾﯽ ﻋﺼﺎره ﻫﺎي آوﯾﺸﻦ دﻧﺎﯾﯽ و ﭼﺎي ﺳﺒﺰ ﺑﺮ وﯾﮋﮔﯽ ﻫﺎي ﺷﯿﻤﯿﺎﯾﯽ و ﻣﯿﮑﺮوﺑﯽ ﮔﻮﺷﺖ ﻣﺎﻫﯽ ﻗﺰل آﻻي رﻧﮕﯿﻦ ﮐﻤﺎن در زﻣﺎن ﻧﮕﻪداري در ﺣﺎﻟﺖ اﻧﺠﻤﺎد ﺑﻮد. در اﯾﻦ ﻣﻄﺎﻟﻌﻪ ﻋﺼﺎره ﻫﯿﺪرواﺗﺎﻧﻮﻟﯽ ﺑﺮگ ﭼﺎي ﺳﺒﺰ و آوﯾﺸﻦ دﻧﺎﯾﯽ ﺑﺎ اﺳﺘﻔﺎده از روش ﺧﯿﺴﺎﻧﺪن اﺳﺘﺨﺮاج و ﺗﺮﮐﯿﺒﺎت آن ﻫﺎ ﺑﺎ روش HPLC ﺷﻨﺎﺳﺎﯾﯽ ﺷﺪﻧﺪ. ﻋﺼﺎره ﻫﺎ در ﻏﻠﻈﺖ ﻫﺎي 0/5 درﺻﺪ ﺑﻪ ﺻﻮرت ﺗﮑﯽ و ﺗﺮﮐﯿﺒﯽ ﺟﻬﺖ ﭘﻮﺷﺶ دﻫﯽﮔﻮﺷﺖ ﻣﺎﻫﯽ ﻗﺰل آﻻي رﻧﮕﯿﻦ ﮐﻤﺎن ﻣﻮرد ﺑﺮرﺳﯽ ﻗﺮار ﮔﺮﻓﺘﻨﺪ. ﻧﻤﻮﻧﻪ ﻫﺎ ﺑﻪ ﻣﺪت 60 روز در دﻣﺎي18- درﺟﻪ ﺳﻠﺴﯿﻮس در ﻓﺮﯾﺰر ﻧﮕﻪداري ﺷﺪﻧﺪ. ﻧﻤﻮﻧﻪ ﻫﺎ در ﻓﻮاﺻﻞ 10روز از ﻧﻈﺮ pH ، ازت ﺗﺎم ﻓﺮار، ﻣﯿﺰان ﺗﯿﻮﺑﺎرﺑﺒﺘﻮرﯾﮏ اﺳﯿﺪ ، ﺷﻤﺎرش ﻟﯿﺴﺘﺮﯾﺎ ﻣﻨﻮﺳﯿﺘﻮژﻧﺰ و ﺧﺼﻮﺻﯿﺎت ﺣﺴﯽ ﻣﻮرد ارزﯾﺎﺑﯽ ﻗﺮار ﮔﺮﻓﺘﻨﺪ. ﺑﯿﺸﺘﺮﯾﻦ ﺗﺮﮐﯿﺒﺎت ﻣﻮﺟﻮد در آوﯾﺸﻦ دﻧﺎﯾﯽ و ﭼﺎي ﺳﺒﺰ ﺑﻪ ﺗﺮﺗﯿﺐ ﺗﯿﻤﻮل 39/4، ﮐﺎرواﮐﺮول 36/27 ﻣﯿﻠﯽﮔﺮم در ﮔﺮم و اﭘﯽﮔﺎﻟﻮﮐﺎﺗﭽﯿﻦﮔﺎﻻت 105/88، اﭘﯽﮐﺎﺗﭽﯿﻦ ﮔﺎﻻت 41/2، اﭘﯽﮔﺎﻟﻮﮐﺎﺗﭽﯿﻦ 29/55 و ﮐﺎﻓﺌﯿﻦ 29/45 ﻣﯿﻠﯽﮔﺮم در ﮔﺮم ﺑﻮد. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﻪ در ﻃﯽ زﻣﺎن ﻧﮕﻪداري، ﺗﻤﺎم ﺗﯿﻤﺎرﻫﺎ ﺳﺒﺐ ﮐﺎﻫﺶ ﻣﯿﺰان ازت ﺗﺎم ﻓﺮار، pH، ﺗﯿﻮﺑﺎرﺑﯿﺘﻮرﯾﮏ اﺳﯿﺪ، ﺷﻤﺎرش ﻟﯿﺴﺘﺮﯾﺎ ﻣﻨﻮﺳﯿﺘﻮژﻧﺰ ﻧﺴﺒﺖ ﺑﻪ ﻧﻤﻮﻧﻪ ﺷﺎﻫﺪ ﺷﺪﻧﺪ. ﻫﻤﭽﻨﯿﻦ ﺗﯿﻤﺎر ﺗﺮﮐﯿﺒﯽ)0/5 درﺻﺪآوﯾﺸﻦ دﻧﺎﯾﯽ و 0/5 درﺻﺪﭼﺎي ﺳﺒﺰ( ﺑﻄﻮر ﻣﻌﻨﯽ داري ﺳﺒﺐ ﺑﻬﺒﻮد وﯾﮋﮔﯽ ﻫﺎي ﻣﯿﮑﺮوﺑﯽ،ﺷﯿﻤﯿﺎﯾﯽ و ﺣﺴﯽ ﻧﻤﻮﻧﻪ ﻫﺎ در ﻃﯽ زﻣﺎن ﻧﮕﻪداري ﺷﺪﻧﺪ. ﻟﺬا اﯾﻦ ﻋﺼﺎره ﻫﺎ ﻣﯽﺗﻮاﻧﻨﺪ ﺑﻪ ﻋﻨﻮان ﺗﺮﮐﯿﺒﺎت ﺿﺪ ﻣﯿﮑﺮوﺑﯽ و آﻧﺘﯽ اﮐﺴﯿﺪاﻧﯽ در ﺻﻨﺎﯾﻊ ﮔﻮﺷﺖ ﻣﻮرد اﺳﺘﻔﺎده ﻗﺮار ﮔﯿﺮﻧﺪ.

Fish meat is as one the most important source of protein and high spoilage feature. Therefore, the aim of this study was to evaluate the synergistic effects of Thymus daenensis (TD) and Camellia sinensis (CS) hydro-alcoholic extracts on chemical and microbial properties of rainbow trout during frozen storage. In this experimental study, hydro-alcoholic extracts of TD and CS were extracted using maceration method and determined their compounds by HPLC. Extracts in 0.5% concentrations were studied separately and in combination for coating rainbow trout meat. The coated fish fillet was kept at -18 °C for 60 days and subjected to pH-testing, total volatile nitrogen (TVN), thiobarbituric acid (TBA), count of Listeria monocytogenes and sensory evaluation every 10 days. Major compounds in Thymus daenensis and Camellia sinensis extracts were thymol (39.4 mg/g), carvacrol (36.27 mg/g) and epigallocatechin gallate (105.88 mg/g), epicatechin gallate (41.2 mg/g), epigallocatechin (29.55 mg/g) and caffeine (29.45 mg/g), respectively. The results showed that during the storage period, all treatments reduced TVN, pH, TBA, count of L. monocytogenes compared to the control sample. Also, combination treatment (0.5% thyme and 0.5% green tea) significantly improved the chemical, microbial and sensory properties of fish fillet during storage.Therefore, green tea and thyme can be used as antimicrobial and antioxidant compounds in meat industry.