African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5232

Full Length Research Paper

An innovative microwave process for microbial decontamination of spices and herbs

Basem F. Dababneh  
Department of Nutrition and Food Processing, Faculty of Agricultural Technology, Al–Balq'a Applied University, Jorda
Email: [email protected]

  •  Accepted: 20 November 2012
  •  Published: 19 February 2013


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 10CFU/g, fungi 1.04 x 103 to 2.2 x 10CFU/g and coliforms < 10to 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