Bridging technique failure through low-tech improvisation: A case study of food microbiology

Research output: Contribution to journalArticle


Modern technology for food safety studies includes standardized protocols and equipment. However, appropriate technology needs to step in to bridge technology dys- or malfunctioning. We examined different low-tech methods for extraction of bacteria from fresh vegetables. Standard equipment including stomacher and filter bags were compared to extraction using bread stick and alternative filter material (nylon stocking, mosquito net). Comparison of microspheres’ (ø: 53-63 µm; ø: 63-75 µm) passage through filter bags, nylon stockings with different densities (15 DEN, 20 DEN, 25 DEN, 40 DEN) and mosquito net showed no significant difference between filter bag and nylon stocking. A significantly higher number of both size microspheres (ø: 53-63 and ø: 63-75 µm) passed through the mosquito net than filter bag and nylon stocking. Manual extraction of romaine lettuce leaf was performed by three technicians. Viable counts of leaf associated bacteria were influenced by the technician and choice of filter material. Viable bacterial counts obtained from breadstick with filter bag manual extraction did not show any significant difference from standard method. We conclude that standard procedures can be replaced by low-tech approaches in the event of malfunctioning equipment. However, method validation is imperative.


  • Most Tahera Naznin
  • Sofia Widstam
  • Rumana Akter
  • Lars Mogren
  • Hanna Y Berhane
  • Yemane Berhane
  • Eva-Charlotte Ekström
  • Magnus Jirström
  • Beatrix W. Alsanius
External organisations
  • Swedish University of Agricultural Sciences
  • Addis Continental Institute of Public Health
  • Uppsala University
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Social Sciences Interdisciplinary
  • Food Science
Original languageEnglish
Article number6DAB22F64345
Pages (from-to)361-365
Number of pages5
Issue number7
Publication statusPublished - 2020 Jul 7
Publication categoryResearch