Abstract

The microbiological status of some dried spices and herbs from local markets in Jordanand the effect of home microwave on reducing their microbial load were evaluated. The results indicated that the sixteen tested samples were contaminated with aerobic mesophilic bacteria ranging from 1.18 x 10³ to 5.1 x 10⁵ CFU/g, mesophilic spore former bacteria 1.2 x 10² to 1.2 x 10⁴ CFU/g, thermophilic spore former bacteria 4.8 x 10² to 1.2 x 10³ CFU/g, fungi 1.04 x 10³ to 2.2 x 10⁴ CFU/g and coliforms < 10² to 3.44 x 10² CFU/g.Salmonella and Staphylococcus aureus were not detected. According to the international standards, 87.5% of the samples were unsatisfactory because of the large population of fungi (87.5%) and coliforms (37.5 %). Exposure of spices and herbs (dry and wet treatments) to microwave resulted in a reduction of the microbial population. In both treatments and at 30 s exposure, the total counts of fungi were decreased by 1-3 log cycle (D values = 0.188 to 0.450 min). Thermophilic spore former bacteria were reduced by 1-2 log cycle (D values = 0.165 to 0.357 min). This novel short period decontamination process could be suitable for use at home and at industrial levels. In addition, implementation of an authorized food control program could prevent the harmful contamination effect on human.

Key words: Spices and herbs, microwave, microbiological quality, D value, microbial decontamination