Table 1.
Microbiological quality of milk and milk products in West Africa 1.
| Country | Milk Source | Milk Product | Processing Technique |
Microorganism | Prevalence n/N 2 (%) | Mean log CFU 3/mL |
Reference |
|---|---|---|---|---|---|---|---|
| Benin | Cow | Raw milk | None | Fecal coliform bacteria | NR 4 | 2.96 | [96] |
| Escherichia coli | 0.60 | ||||||
| Staphylococcus aureus | 1.60 | ||||||
| Benin | Cow | Raw milk | None | Listeria monocytogenes | 9/30 (30.0) | NR | [97] |
| Burkina Faso | NR | Raw milk | None | E. coli | 19/50 (38.0) | NR | [98] |
| Salmonella enterica | 3/50 (6.0) | ||||||
| Curd milk | NR | E. coli | 22/50 (44.0) | ||||
| Burkina Faso | NR | Raw milk | None | E. coli | 5/15 (33.0) | NR | [45] |
| Klebsiella spp. | 15/15 (100.0) | ||||||
| K. pneumoniae | 10/15 (66.7) | ||||||
| Enterobacter spp. | 13/15 (86.7) | ||||||
| Enterobacter cloacae | 10/15 (66.7) | ||||||
| Sour milk | NR | E. coli | 2/15 (13.3) | ||||
| Klebsiella spp. | 5/15 (33.3) | ||||||
| K. pneumoniae | 3/15 (20.0) | ||||||
| Enterobacter spp. | 3/15 (20.0) | ||||||
| Enterobacter cloacae | 1/15 (6.7) | ||||||
| Yogurt | NR | E. coli | 1/15 (6.7) | ||||
| Klebsiella spp. | 4/15 (26.7) | ||||||
| K. pneumoniae | 4/15 (26.7) | ||||||
| Enterobacter spp. | 2/15 (13.3) | ||||||
| Enterobacter cloacae | 2/15 (13.3) | ||||||
| Burkina Faso | Cow | Gappal | Combined fermentation of raw or sour milk and millet dough | Enterobacteriaceae | 13/106 (12.3) | [99] | |
| S. aureus | 10/106 (9.4) | ||||||
| Burkina Faso | Cow | Farm milk | None | E. coli | 68/69 (98.6) | NR | [100] |
| Raw milk | None | 29/84 (34.5) | |||||
| Curd milk | NR | 29/89 (32.6) | |||||
| Pasteurized milk | NR | 29/101 (28.7) | |||||
| Yogurt | NR | 4/92 (4.4) | |||||
| Déguè | NR | 14/87 (16.1) | |||||
| Burkina Faso | Camel | Fermented milk | NR | Coliform bacteria | 21/24 (87.5) | NR | [101] |
| S. aureus | 19/24 (79.2) | ||||||
| Cow | Coliform bacteria | 45/50 (90.0) | |||||
| S. aureus | 42/50 (84.0) | ||||||
| Goat | Coliform bacteria | 33/40 (82.5) | |||||
| S. aureus | 31/40 (77.5) | ||||||
| Burkina Faso | Cow | Lait caillé | Spontaneous fermentation in covered plastic containers at ambient temperature | Enterobacteriaceae | NR | 5.80 | [102] |
| Enterococcus faecium | NR | ||||||
| Côte d’Ivoire | Reconstituted powdered milk | Lait caillé | Fermentation started with addition of commercial yogurt | Coliform bacteria | 99/100 (99.0) | 4.63 | [103] |
| E. coli | 51/100 (51.0) | 4.08 | |||||
| Salmonella spp. | 57/100 (57.0) | NR | |||||
| Côte d’Ivoire | Cow | Raw milk | None | E. coli | NR/NR (70.5) | NR | [104] |
| S. aureus | NR/NR (17.6) | ||||||
| Enterococcus spp. | NR/NR (58.8) | ||||||
| Ghana | Cow | Nunu | Spontaneous fermentation in calabashes or rubber buckets for 1–2 days | Enterobacter | NR | NR | [105] |
| Klebsiella | |||||||
| E. coli | |||||||
| Proteus vulgaris | |||||||
| Shigella | |||||||
| Ghana | Cow | Raw milk | None | Yersinia spp. | 19/98 (19.9) | NR | [42] |
| Klebsiella spp. | 15/98 (15.6) | ||||||
| Proteus spp. | 7/98 (7.3) | ||||||
| Enterobacter spp. | 6/98 (6.3) | ||||||
| E. coli | 2/98 (2.1) | ||||||
| Staphylococcus spp. | 14/98 (14.6) | ||||||
| Bacillus spp. | 11/98 (11.5) | ||||||
| Mycobacterium spp. | 1/98 (1.0) | ||||||
| Ghana | Cow | Raw milk | None | E. coli | 28/224 (12.5) | NR | [106] |
| Ghana | Cow | Nunu | Spontaneous fermentation in calabashes or rubber buckets for 1–2 days | Enterococcus faecium | NR | NR | [32] |
| Ghana | Cow | Raw milk | None | E. coli | 74/150 (49.3) | NR | [107] |
| Ghana | Cow | Brukina | Milk was boiled for 1 h then fermentation was started by back slopping and continued overnight at room temperature | Coliform bacteria | NR | 2.91 | [108] |
| S. aureus | 4.68 | ||||||
| Ghana | Cow | Raw milk | None | Listeria spp. | 20/114 (17.5) | NR | [109] |
| L. monocytogenes | 10/114 (8.8) | ||||||
| Nunu | Spontaneous fermentation | Listeria spp. | 11/84 (13.1) | ||||
| L. monocytogenes | 4/84 (4.7) | ||||||
| Ghana | Cow | Raw milk | None | E. coli O157:H7 | 1/58 (1.7) | NR | [110] |
| Boiled milk | Boiling | E. coli O157:H7 | 12/19 (63.2) | ||||
| S. aureus | 6/19 (31.6) | ||||||
| Nunu | Spontaneous fermentation | E. coli O157:H7 | 3/9 (33.3) | ||||
| S. aureus | 1/9 (11.1) | ||||||
| Brukina | Fermented milk and millet | E. coli O157:H7 | 6/21 (28.6) | ||||
| S. aureus | 1/21 (4.8) | ||||||
| Raw wagashi | Soft cheese made without fermentation | E. coli O157:H7 | 1/17 (5.9) | ||||
| Salmonella enterica | 3/17 (17.7) | ||||||
| Ghana | Cow | Boiled milk | Boiling over open flame for up to 1 h | Fecal coliform bacteria | NR | 0.72 | [111] |
| E. coli | NR | ||||||
| K. pneumoniae | NR | ||||||
| Brukina | Fermented milk and millet | Fecal coliform bacteria | 2.59 | ||||
| E. coli | NR | ||||||
| K. pneumoniae | NR | ||||||
| Raw wagashie | Coagulating fresh milk with extracts of the Sodom apple plant | Fecal coliform bacteria | 4.97 | ||||
| E. coli | NR | ||||||
| K. pneumoniae | NR | ||||||
| Fried wagashie | Deep frying | E. coli | NR | ||||
| K. pneumoniae | NR | ||||||
| Yogurt | NR | Fecal coliform bacteria | 1.43 | ||||
| E. coli | NR | ||||||
| K. pneumoniae | NR | ||||||
| Mali | Cow | Raw milk | None | Coliform bacteria | 5/6 (83.3) | 4.21 5 | [112] |
| E. coli | 2/6 (33.3) | 5.99 5 | |||||
| Curdled milk | NR | Coliform bacteria | 4/12 (33.3) | 6.76 5 | |||
| E. coli | 4/12 (33.3) | 6.66 5 | |||||
| Nigeria | NR | Pasteurized milk | NR | Salmonella spp. | 2/13 (15.4) | 1.83 | [113] |
| Streptococcus spp. | 5/13 (38.5) | 3.32 | |||||
| Enterococcus spp. | 3/13 (23.1) | 3.34 | |||||
| Pseudomonas spp. | 3/13 (23.1) | 2.38 | |||||
| Yogurt | E. coli | 4/15 (26.7) | 1.48 | ||||
| S. aureus | 3/15 (20.0) | 3.37 | |||||
| Streptococcus spp. | 9/15 (60.0) | 3.48 | |||||
| Enterococcus spp. | 3/15 (20.0) | 3.15 | |||||
| Klebsiella spp. | 2/15 (13.3) | 3.22 | |||||
| Nigeria | NR | Raw milk | None | S. aureus | 6/80 (7.5) | NR | [114] |
| Nono | Fermentation | 8/80 (10.0) | |||||
| Nigeria | Cow | Raw milk | None | S. aureus | 17/100 (17.0) | NR | [115] |
| MRSA 6 | 15/100 (15.0) | ||||||
| Wara | NR | S. aureus | 35/100 (35.0) | ||||
| MRSA | 35/100 (35.0) | ||||||
| Nigeria | Cow | Raw milk | None | E. coli | 15/160 (9.4) | NR | [116] |
| E. coli O157:H7 | 3/160 (1.9) | ||||||
| Fermented milk | NR | E. coli | 9/100 (9.0) | ||||
| E. coli O157:H7 | 2/100 (2.0) | ||||||
| Nigeria | Cow | Nono | Fermentation | E. coli | 27/100 (27.0) | NR | [117] |
| Enterobacter spp. | 8/100 (8.0) | ||||||
| Klebsiella spp. | 6/100 (6.0) | ||||||
| Proteus spp. | 3/100 (3.0) | ||||||
| Citrobacter spp. | 2/100 (2.0) | ||||||
| Senegal | NR | Raw milk | None | Coliform bacteria | NR | 4.93 | [44] |
| Salmonella Johannesburg | 1/15 (6.7) | NR | |||||
| Coxiella burnetii | 6/15 (40.0) | NR | |||||
| Coagulase-positive Staphylococcus | NR | NR | |||||
| Pasteurized milk | NR | Coliform bacteria | NR | 7.51 | |||
| Coagulase-positive Staphylococcus | NR | NR |
1 Adapted from [39]. 2 Number of positive samples/total number of samples. 3 Colony forming units. 4 Not reported. 5 Most probable number (MPN)/100 mL. 6 Methicillin-resistant S. aureus.