African Journal of
Food Science

  • Abbreviation: Afr. J. Food Sci.
  • Language: English
  • ISSN: 1996-0794
  • DOI: 10.5897/AJFS
  • Start Year: 2007
  • Published Articles: 972

Full Length Research Paper

The microbial quality of pre-packed mixed vegetable salad in some retail outlets in Lagos, Nigeria

R. E. Uzeh1*, F. A. Alade, 1 and M. Bankole2
  1Department of Botany and Microbiology, University of Lagos, Lagos, Nigeria. 2Nigerian Institute of Medical Research, Lagos, Nigeria.
Email: [email protected]

  •  Accepted: 25 August 2009
  •  Published: 30 September 2009

Abstract

 

Pre-packed mixed vegetable salad and salad ingredients- carrots, cucumber, cabbage, and lettuce were analyzed for their microbial quality. The salads were obtained from fast food outlets (well packaged at 4oC) and open markets (exposed at 35oC) within Lagos metropolis. The analysis was both qualitative and quantitative. Microorganisms isolated from salad samples from fast food outlets include Aspergillus fumigatus, Trichoderma spp, Staphylococcus aureus andProteus mirabilis, while those isolated from open market samples include Mucorspp, A. fumigatus, Aspergillus niger, Trichoderma spp, Neurospora crassa,Proteus vulgarisS. aureusCitrobacter freundii, Proteus mirabilis, andCorynebacterium spp. Those from salad ingredients include Mucor spp, A. fumigatus, Trichoderma spp, N. crassaRhizopus spp, A. nigerP. vulgarisP. mirabilisS. aureus, Pseudomonas aeruginosa and C. fruendii. The total viable count was highest in salad samples from open markets (5.9×106 cfu/g) and lowest in salad samples from fast food outlets (2.6 × 104 cfu/g). The total viable counts obtained from the salad ingredients were generally lower than those obtained from salads. Among the salad ingredients the highest count was however obtained from carrot (3.0 × 10cfu/g) and lowest count from cucumber (1.3 × 102 cfu/g). Gentamicin, chloramphenicol, cotrimoxazoleoflaxacin were most effective against the bacterial isolates yielding greater zones of inhibition.  The storage temperature and the dirty nature of the open markets must have been responsible for the occurrence of more microorganisms in salad samples from open markets than those from fast food outlets. The need for safe salad can not be overemphasized.

 

Key words: Vegetable salad, salad ingredients, microorganisms, fast food outlets, open markets.