African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5093

Full Length Research Paper

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

Most Tahera Naznin
  • Most Tahera Naznin
  • Department of Biosystems and Technology, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden.
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Sofia Windstam
  • Sofia Windstam
  • Department of Biosystems and Technology, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden.
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Rumana Akter
  • Rumana Akter
  • Department of Biosystems and Technology, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden.
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Lars Mogren
  • Lars Mogren
  • Department of Biosystems and Technology, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden.
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Hanna Y. Berhane
  • Hanna Y. Berhane
  • Addis Continental Institute of Public Health, 26751/1000 Addis Ababa, Ethiopia.
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Yemane Berhane
  • Yemane Berhane
  • Addis Continental Institute of Public Health, 26751/1000 Addis Ababa, Ethiopia.
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Eva-Charlotte Ekström
  • Eva-Charlotte Ekström
  • Department of Women’s and Children Health, International Maternal and Child Heath, Uppsala University, 751 85 Uppsala, Sweden.
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Magnus Jirström
  • Magnus Jirström
  • Department of Human Geography, Faculty of Social Sciences, Lund University, 223 62 Lund, Sweden.
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Beatrix W. Alsanius
  • Beatrix W. Alsanius
  • Department of Biosystems and Technology, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden.
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  •  Received: 23 April 2020
  •  Accepted: 07 July 2020
  •  Published: 31 July 2020

Abstract

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.

 

Key words: Homogenizer, low-tech method, microbial load, romaine lettuce.