Comparison of the performance of bromophenol blue and bromocresol green Sensors in determining the microbial spoilage of (Clupeonella cultriventris caspia) stored in the refrigerator

In this study, a sensor based on chitosan biofilm with bromophenol blue and bromocresol green sensors based on filter paper were used to determine the bacterial quality of common Kilka fish mince in refrigerated temperature. The total viable bacterial count (TVCs) on day zero was 3.473 log CFU / gr, which at the end of the storage period was changed to 6.497 log CFU / gr (p <0.05). The psychrotrophic bacterial counts (PTCs) at the beginning storage time was a 1.473 log CFU / gr and increased during the refrigerated storage time and achieved to 7.516 log CFU / gr (p <0.05). Total volatile basic nitrogen (TVB-N) at the beginning of the storage period was 7.01mg N/100g, which increased to 44.348 mg N/100g at the end of the storage (p <0.05). The pH during storage time changed from 6.105 to 6.827 (p <0.05). The correlation among microbial, chemical and color change values (ΔE) was different, and the highest correlation was observed in bromophenol blue indicator, which correlates with TVCs, The PTCs, TVB-N and pH were 0.941, 0.989, 0.912 and 0.779, respectively (p <0.05). Based on the results of this study, it was found which bacterial and chemical changes spoilage in the minced fish package was simultaneous with the sensors color change and they show a quality decrease as form color change.