Mathematical modeling of microbial load in poultry meat fillets according to Impedance-Splitting method and evaluation it's correlation with total volatile nitrogen (TVN)

Measuring total microbial count of poultry meat with conventional pour plate method and comparing the results with standard limits is one of the routine tests. Achieving the results of total microbial count in minimum time is really important for confidence from the hygienic quality of products. So impedance – splitting method as a new technique for this purpose was considered in order to receiving the results in a shorter time and as soon as possible. The main purpose of this study، was to evaluate the correlation between impedance detection time (IDT in hrs)، total microbial population (log10 N) and total volatile nitrogen (TVN) of poultry meat fillets. Totally 80 samples (40 samples in warm season and 40 samples in cold season) were collected and examined under sterile conditions. The total microbial count by pour plate technique and impedance – splitting method، also measuring total volatile nitrogen were carried out based on the recommendations of Iran''s Standard Institute and Industrial Investigation. Then the calibration curves of 3 methods and their equations were obtained by using Excel software. The calibration curves of methods were elaborated for total microbial count and impedance detection time، demonstrating a good correlation between the two methods in cold and warm season and also all of samples equal to 98. 1%، 97. 3% and 97. 4%، respectively. Also according to the calibration curves، the correlation between impedance detection time and total volatile nitrogen in cold and warm season and also all of samples were equal to 81. 5%، 85. 4% and 82. 5% respectively. Also the correlation between total microbial count and total volatile nitrogen in cold and warm season and also all of samples were equal to 83. 2%، 86. 8% and 84. 4%، respectively for poultry meat samples. Therefore، impedance measurement which is a more rapid، automated and less laborious method than conventional technique could be used as an alternative method for the rapid quality evaluation in foods instead of conventional methods.