title: Application of microwaves for microbial load reduction in black pepper (Piper nigrum L.).
abstract: BACKGROUND
  Black pepper (Piper nigrum L.) is exposed to microbial contamination which could potentially create public health risk and also rejection of consignments in the export market due to non-adherance to microbial safety standards. The present study investigates the use of microwave (MW) radiation for microbial load reduction in black pepper and analyses the effect on quality.
  
  
  RESULTS
  Black pepper was exposed to MWs at two different power levels (663 and 800 W) at an intensity of 40 W g(-1) for different time intervals (1-15 min) and moisture content (110 and 260 g kg(-1) on a wet basis). The exposure of black pepper to MWs at 663 W for 12.5 min was found to be sufficient to reduce the microbial load to the permissible level suggested by the International Commission on Microbiological Specifications for Foods and the European Spice Association. The retention of volatile oil, piperine and resin was 91.3 ± 0.03, 87.6 ± 0.02 and 90.7 ± 0.05%, respectively, in MW-treated black pepper. The final moisture content after MW treatment was found to be 100 ± 1 g kg(-1) for black pepper containing initial moisture of 260 ± 3 g kg(-1) .
  
  
  CONCLUSIONS
  These results suggest that MW heating can be effectively used for microbial load reduction of black pepper without a significant loss in product quality. © 2016 Society of Chemical Industry.
authors.affiliation: Department of Food Engineering, Central Food Technological Research Institute (CFTRI), Mysore, Karnataka, 570 020 India.
authors.forename: G Chengaiyan
authors.initials: GC
authors.lastname: Jeevitha
authors.affiliation: Department of Spice and Flavor Science, CSIR - Central Food Technological Research Institute (CFTRI), Mysore, Karnataka 570 020, India.
authors.forename: H Bogegowda
authors.initials: HB
authors.lastname: Sowbhagya
authors.affiliation: Department of Food Engineering, Central Food Technological Research Institute (CFTRI), Mysore, Karnataka, 570 020 India.
authors.forename: H Umesh
authors.initials: HU
authors.lastname: Hebbar
mesh_terms: D058491:Bacterial Load / Q000528:radiation effects*; D005506:Food Contamination / Q000517:prevention & control; D005516:Food Microbiology / Q000379:methods; D005519:Food Preservation / Q000379:methods*; D063427:Food Quality; D059022:Food Safety / Q000379:methods; D005658:Fungi / Q000528:radiation effects*; D006361:Heating; D050296:Microbial Viability / Q000528:radiation effects; D008872:Microwaves; D029222:Piper nigrum / Q000737:chemistry / Q000382:microbiology* / Q000528:radiation effects*
keywords: black pepper; microbial load reduction; microwave; piperine; volatile oil