Predictive model design for microbial load based on impedance in traditional and industrial dried vegetables

This study was aimed to use of impedance technique and comparison of its results with reference method in traditional and industrial dried vegetables. In this study, 30 samples of traditional dried vegetable and 30 samples of industrial dried vegetable were tested for microbial counts by reference method of culture and Impedance device in accordance with the Instruction of Standards and Industrial Research Institute of Iran. The impedance method showed the minimum and maximum number of microorganisms in traditional samples were 4.80 × 104 and 1.40 × 106 bacteria per gram respectively. The minimum and maximum number of microorganisms in industrial samples were 6.00 × 102 and 7.00 × 105 bacteria per gram, respectively. The maximum detection time in impedance method in industrial and traditional dried vegetables was 20.24 and 23.68 hours, respectively and minimum detection time in industrial and traditional samples was 11.35 and 8.25 hours. The results showed determination coefficients of bacterial load in dried vegetable by regression equations were 0.9169, 0.9133 and 0.8861 in traditional, industrial and total of two method dried vegetables respectively. It indicates that high correlation was between reference and impedance methods for traditional and industrial dried vegetables. Microbial load in traditional and industrial dried vegetables was higher and lower than that of standard limit, respectively. Therefore, impedance technique could be used as an alternative method for control of bacterial load in dried vegetable.