Microbial Contamination at Different Stages of Production of Ogi in Mowe: A Rural Community, Southwest, Nigeria
The reported cases of outbreaks of communicable diseases and high child mortality in the developing countries have been linked to food and water contamination due to poor sanitary conditions. The microbial assessment at critical points of production of Ogi was aimed at establishing the source(s) of contamination. The water samples, maize grains, paste and filtrate, wet Ogi, body swabs and underneath of nails of the attendants were screened for microbial presence. The organisms were isolated from 10-3 and 10-7 dilution of water; steep water after soaking of grains, mashed grains, paste and filtrate and fermented wet Ogi, respectively on Potato Dextrose (Fungi), Mueller Hilton (Bacteria) and Sabouraud Dextrose (Yeasts) agar. The enteric organisms were further confirmed on MacConkey and Mannitol salt agar. The isolated organisms included Aspergillus flavus, A. niger, Penicillium oxalicum, Fusarium oxysporium and Rhizopus stolonifer (Fungi), Candida albicans and Saccharomyces cerevisiae (Yeast), Escherichia coli and Klebsiella aerogenes (Enteric bacteria), Lactobacillus plantarum, Pseudomonas aeruginosa and Staphylococcus aureus (Non enteric bacteria). The non enteric bacteria were contained in all the samples screened while the growth of the enteric bacteria and fungi species was significantly inhibited at the latter stages of fermentation. There was a re-contamination of the paste and fermented Ogi by the enteric bacteria due to poor handling and unhygienic practices associated with the attendants. The water samples, soaking medium, grinding mill and transportation from storage to selling points were the critical points of contamination. Appropriate safety measures and good manufacturing practices will ensure good quality of product.
to cite this article:
O.A. Oyelana and A.A. Coker, 2012. Microbial Contamination at Different Stages of Production of Ogi in Mowe: A Rural Community, Southwest, Nigeria. Bacteriology Journal, 2: 1-11.
Received: August 25, 2011;
Accepted: October 10, 2011;
Published: January 23, 2012
Maize products are the cheapest and readily available fermented foods for infants
and young adults in most tropical countries (Torre et
al., 1991). They are important energy food rich in carbohydrates and
with traces of vitamins, proteins and minerals (Achterberg
et al., 1994; FAO, 2009) and are natural antioxidants
(Eaton and Nelson, 1991). The importance of vitamins
as antioxidants was aptly discussed by Singh and Sachan
The wet fermented porridge is prepared and consumed as Ogi, Akamu and Akassa
among the Yorubas, Ibos and Hausas in the west, east and northern Nigeria, respectively
(Parveen and Hafiz, 2003). These maize products are
common in seemingly poor and impoverished communities across the developing
countries (Inyang and Idoko, 2006). These fermented
products are largely from Zea mays, Oryza sativa, Sorghum valgare
and Triticum aestivum. Their production is often by small-scale enterprise
undertaken by unskilled female attendants (Aminigo and Akingbala,
The maize porridge has become part of the stable diets (Adeyemi
and Soluade, 1993) for young adults, nursing mothers and a weaning ration
for infants between the ages of 1 and 2 years (Adebolu
et al., 2007). It is a choice meal for patients in need of soft and
easily digestible foods (Jay, 2005). The nutritive quality
of maize porridge is very low resulting from low quality of maize proteins and
the substantial loss of nutrients at the different stages of production (Nkama
et al., 2000). Consequently, a number of leguminous seeds including
Soya beans and Okra seeds are used to fortify and improve their protein, iron,
calcium and fibre contents (Osungbaro, 2009; Anigo
et al., 2009; Olukoya et al., 1994)
to eliminate the incidences of anaemia and stunted growth often associated with
malnutrition (Muhimbula and Issa-Zacharia, 2010).
The inclusion of fumonisin and aflatoxins in maize (Jespersen
et al., 1994) and other cereal products (Fandohan
et al., 2005; Shephard et al., 2002)
has been linked to certain species of fungi including Aspergillus, Penicillium,
Rhizopus and Fusarium by Omemu et al.
The carcinogenic effects of this contamination were extensively discussed by
Shephard et al. (2002). Few of these toxins including
FB1 are associated with high degree of cancer in rats and humans. Hendricks
(1999) and Barug et al. (2004) warned of the
health implication of consuming mycotoxins contaminated maize products. Fandohan
et al. (2005) warned of the danger of using the supernatant from
Ogi as solvent to extract active ingredients from traditional herbal plants
because of probable high level of fumonisin. A positive correlation between
the level of aflatoxins and the incidences and severity of kwashiorkor in infants
(Adhikari et al., 1994) has been established.
They also discovered a significantly low haemoglobin level, longer oedema and
increased infection rate in children that were positive for aflatoxins.
The death toll as a result of microbial contamination of foods remains ever
high in the developing countries. Over 38, 173 cases of cholera outbreaks were
reported between January and August, 2010 in Nigeria. This figure was three
times the number reported for the year 2009 (WHO, 2010).
The incidence was aptly linked to contamination of food and poor hygienic conditions.
Osho and Fagade (2000) reported outbreaks of cholera,
typhoid fever, infectious hepatitis and gastroenteritis in Ago-Iwoye, Southwest,
Nigeria and adduced similar reasons for the high death of infants and young
adults. A correlation between high mortality rate in infants and low income
families was reported by Uddian and Hossain (2008).
The poor hygienic practices associated with the preparation of Ogi and other
cereal products makes it a source of infection when consumed by young adults
and infants. Consequently, the study aims at establishing the critical points
of contamination during the preparation of Ogi and suggest appropriate control
MATERIALS AND METHODS
The study was conducted at the facilities of Biological Sciences Department, Redeemers University, Nigeria from September 2010 to March, 2011.
Collection of samples: Three production and storage sites were chosen in Mowe, a border town between Lagos and Ogun States and a fast growing rural community 41 with a population close to 100, 000 people. Samples were collected from water in reservoirs (plastic/metal tanks and drums), maize grains, steep water from mashed grains, paste, filtrate from paste and fermented slurry (wet pap). Collection of samples was done twice a month, spanning over four months, starting December, 2010 to March, 2011. The samples were collected in sterile bottles and immediately stored at 4°C temperature until ready for use. Swaps from finger nails, clothes and cooking utensils were collected using moist sterile cotton wool.
Production of Ogi (Liquid porridge from maize): The maize grains were sieved to remove pebbles and dirts and subsequently soaked in water for 4 days. The soft grains were mashed, milled and sieved using Muslin cloth. The solid paste was diluted with water and left to ferment for 48-72 h. The surface water was decanted and the sediment (wet slurry) was collected in a bowl and allowed to stand for 8-10 h to sufficiently solidified. The solidified slurry was portioned into small units or cubes and wrapped in leaves or polythene bags ready for sale.
Media preparation: The techniques described by Arora
and Arora (2008) and Willey et al. (2008) were
employed in preparing the Potato Dextrose (PDA) and Mueller Hilton agar to obtain
pure cultures of the fungal and bacterial isolates, respectively.
Fungi: Serial dilutions of the samples of water (10-3) and steep
water, mashed grains, paste, filtrate from paste and fermented wet slurry (10-7)
were obtained. The sufficiently diluted samples were mixed with warm agar (PDA)
and poured into Petri dishes to obtain sufficient fungal growth. The upper surfaces
of fungal colonies were picked and inoculated on fresh PDA to obtain pure cultures
using the techniques described by Willey et al. (2008).
Yeast: The sufficiently diluted samples were mixed with warm Sabouraud
Dextrose (SDA) agar and plated following the techniques described by Marshall
Bacteria: A small part of the diluted samples was pipette onto the centre
of Mueller Hilton agar and spread out evenly over the agar surface with a sterilized
spreader and incubated at 37°C for 24 h (Willey et
al., 2008). The tip of each colony was picked with a sterilized wire
loop and streaked across fresh agar surface to obtain single cell cultures.
Estimation of the viable bacteria colonies was done using the Standard plate
count agar (Difco lab. Detroit Michigan). The experiment was in duplicate.
Air screening: Petri dishes containing PDA and Mueller Hilton agar were sufficiently exposed to air around the production sites for 4 h, incubated at 37°C for 24 h and analysed for fungal and bacterial presence only.
Biochemical tests analysis: The techniques described by Cheesbrough
(2002) were employed for the Gram staining while the citrate utilization,
Hydrogen sulphide production test and sugar fermentation and oxidase tests were
as, respectively described by MacWilliams (2009) and
Cowan and Steel (2002). The isolates were later identified
using Bergeys manual described by Brenner et al.
(2005). Confirmation of coliforms was as described by Willey
et al. (2008) using selective and differential media such as MacConkey
and Mannitol salt agar to analyse for E. coli and Klebsiella sp.
and Staphylococcus aureus, respectively. The presumptive test in broth
was streaked out on Mueller Hilton agar and incubated at 37°C for 48 h to
morphologically characterize the isolates.
The water samples from the three study sites consisted of Aspergillus niger, A. flavus, Penicillium oxalicum, Fusarium oxysporium and Rhizopus stolonifer (Table 1). These organisms were the principal contaminants and found in water used in the washing and soaking of maize, mashed grains and freshly milled maize pastes. The growth of these fungi pathogens were significantly inhibited at the later stages of fermentation (Table 1). They were found suspended in air around the three study sites and also on clothes and body swabs (Table 2) of the attendants.
The two yeast contaminants which included Candida albicans and Saccharomyces
cerevisiae were equally isolated from maize after soaking and under the
nails of attendants and utensils (Table 3). The Lactobacillus
plantarum and Staphylococcus aureus were among the four bacteria
species isolated from both water and at the different stages of production (Table
3a, b). They were equally isolated from under nails and
clothes of the attendants and cooking utensils (Table 3).
The analysis of clothing revealed heavy presence of Pseudomonas aeruginosa.
The surface of grains was almost sterile while the bacteria growth progressively
decline in the steep water, paste and filtrate and fermented Ogi (Table
|| Fungal contamination at stages of production
|a: Water in reservoirs, b: Maize grains, c: Steep water, d:
Maize, e: Filtrate from paste, f: Wet ogi, -: Absent, +: Present
|| Microbial assay of air, utensils and body swabs of the attendants
|a: Air, b: Underneath of nails, c: Boby swabs, d: Clothing,
e: Utensils, -: Absent (no growth), +: Present (growth)
||Estimation (c.f.u. mL-1×
106) of bacteria and yeast population in samples from different
stages of production
|A: Water from tanks (reservoirs), B: Maize grains prior to
soaking, C: Steep wate, D: Miaze paste, E: Filtrate from paste, F: Wet ogi
, 1-3: Sites of collection, I-VIII: Number of sampling-absence of organisms
||Estimation (c.f.u. mL-1×
106) of bacteria and yeast population in samples from different
stages of production
|A: Water from tanks (reservoirs), B: Maize grains prior to
soaking, C: Steep wate, D: Miaze paste, E: Filtrate from paste, F: Wet ogi
, 1-3: Sites of collection, I-VIII: Number of samplingabsence of organisms
There was no significant difference (p = 0.005-ANOVA) in the number of colonies found in all the water sources from the three sites. The growth of E. coli and K. aerogenes declined significantly at complete fermentation stages. These organisms were re-introduced into the preparation at later stages of production as fresh contaminants. The growth of P. aeruginosa, L. plantarum and S. aureus was unaffected (4.00-5.76 cfu mL-1x106) at terminal stages of fermentation.
The outbreak of infectious and communicable diseases in tropical parts of the
world is primarily as a result of food poisoning due to microbial contamination
(Jay, 2005). They are often responsible for acute gastroenteritis,
abdominal discomfort and pain and diarrhoea in infants and young adults (WHO,
2010; Kimmons et al., 1999).
The maize grains were almost surfaced sterile prior to soaking. The isolated
Staphylococcus aureus in few maize samples could have arisen from contaminated
sacks used for storage and transportation of produce. Onovo
and Ogaraku (2007) discovered some bacteria and fungi on exposed Tigernut
(Cyperus esculentus L.) before processing. The presence of Aspergillus
flavus, A. niger, Penicillium oxalicum, Fusarium oxysporium, Rhizopus stolonifer,
Saccharomyces cerevisia Candida albicans Escherichia coli Klebsiella aerogenes
and Staphylococcus aureus in water from the reservoirs suggests an extremely
poor storage system, deplorable sanitary conditions available at the three sites
and multiple sources of contamination due to open access to the reservoirs.
Similar and related organisms were implicated in food and canned products by
Gadaga et al. (2008), Taulo
et al.( 2009) and Oladipo and Omo-Adua (2011).
The exposure of water tanks to direct rays from the sun provided the required
warmth and physical condition for growth of these organisms. Ozoh
and Kuyanbana (1995) and Osho and Fagade (2000)
equally affirmed water as the source of Shigella spp. and E. coli
in maize and other cereal porridge. Contaminated water was linked as the main
source of Vibrio cholera infection (Shahcheraghi
et al., 2009) in some population in Iran. Oranusi
et al. (2007) estimated 2-3 Log10 coliforms per 100 g mL-1
of cooked maize porridge and linked contamination to the water used during washing
and soaking of maize grains. Heavy presence of E. coli, Klebsiella
pneumonia and Streptococcus sp. was reported (Yeboah-Manu
et al., 2010) in some foods sold around the University of Ghana campus.
The introduction Salmonella sp. Rhizopus sp. and Staphylococcus
aureus in some food products have been linked to the presence of phytotoxin
by Okafor and Omodamiro (2006).
The attendants at the three study sites admitted collecting water from streams
and lakes whenever the public water supply failed and often time untreated water
was used during preparation. Good and hygienic water supply has been the bane
of many communities in the developing countries (Ehiri et
al., 2001) including Nigeria where the needed social and infrastructural
facilities are grossly inadequate.
The unlimited and open access to the water tanks allowed cross contamination
of the cooking utensils and bowls and subsequent re-contamination of products
at the later stages of production. The body swabs and underneath of nails contained
substantial counts of Staphylococcus aureus and Lactobacillus plantarum
and also, E. coli, Klebsiella aerogenes and Saccharomyces cerevisiae.
The Muslin clothes used in sieving the shaft were stained and soiled and often
reused without thorough washing. The wrapping leaves and polythene were not
sufficiently rinsed or sterilized before use. Omemu and
Adeosun (2010) observed similar unhygienic practices among attendants and
vendors at some production sites in Abeokuta, Nigeria.
The air was laden with Aspergillus flavus, Penicillium oxalicum and
Rhizopus stolonifer and served as source of re-contamination of the finished
products. Wacher et al. (1993) linked the contamination
of freshly prepared pozol, traditional Mexican fermented maize dough to the
surrounding air. The growth of bacteria (Escherichia coli and Klebsiella
aerogenes) declined significantly in fully fermented wet paste as rightly
observed by Byaruhanga et al. (1999) for Bacillus
cereus after 24 h fermentation. Also, Mensah et al.
(1990, 1991) observed a significant inhibition in
the growth of some gram-negative bacteria. Chukeatirote
et al. (2010) observed an exponential increase in the population
of bacteria and fungi with increased pH and fermentation time of Thua nao (Soybean).
However, a re-contamination at latter stages of production by these enteric
bacteria as observed could be linked to water as it was used repeatedly during
preparation. Odugbemi et al. (1993) reported
an increase in the level of faecal coliforms in cooked Ogi under 9 h storage
conditions and suggested a probable re-introduction during storage. A similar
conclusion was held by Sanni et al. (2002) for
the rise in the population of yeast from 1.0 cfu g-1 to 5.36 cfu
g-1 after 12 h fermentation. Alalade and Adeneye
(2007) observed a significant correlation between pH and coliform bacterial
count in wara cheese during fermentation process.
We observed few counts of Escherichia coli and Klebsiella aerogenes
in fully fermented products (wrapped wet Ogi). Poor handling by vendors was
rightly suggested by Wacher et al. (1993) for
the significant increase in enteric bacteria in freshly prepared pozol. On the
other hand, the growth of Lactobacillus plantarum was unhindered at the
different stages of production, even after 48 h fermentation. Relatedly, an
exponential increase in growth of some lactic acid bacteria was earlier reported
by Kunene et al. (1999) in both fermented and
cooked maize porridge. The critical contamination points during the preparation
of Ogi included the point of soaking of grains, mill and wrapping materials.
Effective GMP as recommended by Amoa-Awua et al.
(2007) would help eliminate contaminants for improved table quality and
assure the health of consumers.
The water samples were the major sources of microbial contamination of products at all the stages of production. The unhygienic practices by attendants were linked to the heavy presence and repeated contamination by A. flavus, A. niger, F. oxysporium, P. oxalicum and R. stolonifer, S. cerevisiae, C. albicans, E. coli, K. aerogenes, P. aeruginosa, L. plantarum and S. aureus. The enteric bacteria and all the fungi species were eliminated at full fermentation while the growth of others was unaffected. The wrapping leaves and surfaces of bowls provided secondary sources of contamination of product. Appropriate training to expose attendants and vendors to safety standards and good manufacturing practices is essential to maintaining quality of products.
This study was executed through the research grant from Redeemers University, Nigeria. Dr. A. Osho provided the manual for identification of the microorganisms and Ms. O.O. Fatoki, typed the manuscript.
Achterberg, C., E. McDonnell and R. Bagby, 1994.
How to put the food quide pyramid into practice. J. Am. Diet Assoc., 94: 1030-1035.PubMed | Direct Link |
Adebolu, T.T., O.A. Olodun and B.C. Ihunweze, 2007.
Evaluation of ogi liquor from different grains for antibacterial activities against some common diarrheal bacteria in Southwest, Nigeria. Afr. J. Biotechnol., 6: 1140-1143.Direct Link |
Adeyemi, I.A. and E.O. Soluade, 1993.
Development and quality evaluation of pawpaw-ogi. Plant Foods Human Nutr., 44: 213-220.PubMed | Direct Link |
Adhikari, M., G. Ramjee and P. Berjak, 1994.
Aflatoxin, kwashiorkor and morbidity. Natural Toxins, 2: 1-3.CrossRef | Direct Link |
Aminigo, E.R. and J.O. Akingbala, 2004.
Nutritive composition and sensory properties of ogi fortified with okra seed meal. J. Applied Sci. Environ. Manage., 8: 23-28.Direct Link |
Amoa-Awua, W.K., P. Ngunjiri, J. Anlobe, K. Kpodo, M. Halm, A.E. Hayford and M. Jakobsen, 2007.
The effect of applying GMP and HACCP to traditional food processing at a semi-commercial kenkey production plant in Ghana. Food Control, 18: 1449-1457.CrossRef |
Anigo, K.M., D.A. Ameh, S. Ibrahim and S.S. Danbauchi, 2009.
Nutrient composition of commonly used complementary foods in North Western Nigeria. Afr. J. Biotechnol., 8: 4211-4216.Direct Link |
Arora, D.R. and B. Arora, 2008.
Textbook of Microbiology. 3rd Edn., CBS Publishers and Distributors, New Delhi, India, Pages: 771
Barug, D., H. van Egmond, R. Lopez-Garcia, T. van Osenbruggen and A. Visconti, 2004.
Meeting the Mycotoxin Menace. Wageningen Academic Publishers, The Netherlands, ISBN: 9076998280, Pages: 320
Brenner, J., R. Kreig and T. Stanley, 2005.
Bergey's manual of systematic bacteriology. The probacteria, Part A. Introductory Essay, 2 : 587-848.
Byaruhanga, Y.B., B.H. Bester and T.G. Watson, 1999.
Growth and survival of Bacillus cereus in mageu, a sour maize beverage. World J. Microbiol. Biotechnol., 15: 329-333.CrossRef |
Cheesbrough, M., 2002.
District Laboratory Practice in Tropical Countries. Cambridge University Press, Cambridge, pp: 97-182
Cowan, S.T. and K.J. Steel, 2002.
Manual for the Identification of Medical Bacteria. 2nd Edn., Cambridge University Press, Cambridge, UK., pp: 51-120
Eaton, S.B. and D.A. Nelson, 1991.
Calcium in evolutionary perspective. Am. J. Clin. Nutr., 54: 281S-287S.PubMed | Direct Link |
Ehiri , J.E., M.C. Azubuike, C.N. Ubaonu, E.C. Anyanwu, K.M. Ibe and M.O. Ogbonna, 2001.
Critical control points of complementary Food preparation and handling in Eastern Nigeria. Bull. World Health Organisation, 79: 423-433.PubMed | Direct Link |
Fandohan, P., D. Zoumenou, D.J. Hounhouigan, W.F.O. Marasas, M.J. Wingfield and K. Hell, 2005.
Fate of aflatoxins and fumonisins during the processing of maize into food products in Benin. Int. J. Food Microbiol., 98: 249-259.PubMed | Direct Link |
Gadaga, T.H., B.K. Samende, C. Musuna and D. Chibanda, 2008.
The microbiological quality of informal vended foods in Harare, Zimbabwe. Food Control, 19: 829-832.CrossRef |
Hendricks, K., 1999.
Fumonisins and neural tube defects in South Texas. Epidemiology, 10: 198-200.Direct Link |
Inyang, C.U. and C.A. Idoko, 2006.
Assessment of the quality of ogi made from malted millet. Afr. J. Biotechnol., 5: 2334-2337.Direct Link |
Jay, J.M., 2005.
Modern Food Microbiology. 4th Edn., CBS Publishers and Distributors, New Delhi, India, ISBN: 81-239-0475-4, Pages: 701
Jespersen, L., M. Halm, K. Kpodo and M. Jacobsen, 1994.
Significance of yeasts and moulds occurring in maize dough fermentation for Kenkey
production. Int. J. Food Microbiol., 24: 239-248.Direct Link |
Kimmons, J.E., K.H. Brown, A. Lartey, E. Collison, P.P.A. Mensah and K.G. Dewey, 1999.
The effects of fermentation and/or vacuum flask storage on the presence of coliforms in complementary foods prepared for Ghanaian children. Int. J. Food Sci. Nutr., 50: 195-201.CrossRef |
Kunene, N.F., J.W. Hastings and A. von Holy, 1999.
Bacterial populations associated with a sorghum-based fermented weaning cereal. Int. J. Food Microbiol., 49: 75-83.Direct Link |
Marshall, R.T., 1993.
Standard Methods for the Microbiological Examination of Dairy Products. 16th Edn., American Public Health Association, Washington, DC
Mensah, P.P.A., A.M. Tomkins, B.S. Drasar and T.J. Harrison, 1991.
Antimicrobial effect of fermented Ghanian maize dough. J. Applied Microbiol., 70: 203-210.CrossRef |
Mensah, P.P.A., A.M. Tomkins, B.S. Drasar and T.J. Harrison, 1990.
Fermentation of cereals for reduction of bacterial contamination of weaning food in Ghana. Lancet, 336: 140-143.CrossRef |
MacWilliams, M.P., 2009.
Citrate test protocols. Microbe Library, American Society of Microbiology. http://www.microbelibrary.org/component/resource/laboratory-test/3203.
Muhimbula, H.S. and A. Issa-Zacharia, 2010.
Persistent child malnutrition in Tanzania: Risks associated with traditional complementary foods. Afr. J. Food Sci., 4: 679-692.Direct Link |
Nkama, I., S. Dappiya, S. Modu and W. Ndahi, 2000.
Physical, chemical, Rheological and sensory properties of Akama from different pearl millet cultures. J. Arid Agric., 10: 145-149.
Odugbemi, T., J.P.O. Oyerinde, O.M.T. Odujinrin, C.O. Akitoye and F.I. Esumeh, 1993.
Bacteriological study of cooked ogi (fermented cereal weaning food) and its potential safety in a rural Nigerian community. Trans. R. Soc. Trop. Med. Hyg., 87: 234-235.CrossRef |
Olukoya, D.K., S.I. Ebigwei, N.A. Olasupo and A.A. Ogunjimi, 1994.
Production of Dogik: An improved Ogi (a Nigerian fermented weaning food) with potential for use in diarrhea control. J. Trop. Pediatrics, 40: 108-113.PubMed | Direct Link |
Omemu, A.M. and O.F. Adeosun, 2010.
Evaluation of hazards and critical control points of ogi in small scale processing centres in Abeokuta, Nigeria. J. Applied Biosci., 29: 1766-1773.Direct Link |
Omemu, A.M., M.O. Edema and M.O. Bankole, 2005.
Bacteriological assessment of street vended ready to eat (RTE) vegetables and pre-packed salad in Nigeria. Nig. J. Microbiol., 9: 497-504.
Oranusi, S.U., M. Galadima, V.J. Umoh and P.I. Nwanze, 2007.
Food safety evaluation in boarding schools in Zaria, Nigeria using the HACCP system. Scient. Res. Essay, 2: 426-433.Direct Link |
Osho, A. and O.E. Fagade, 2000.
Occurrence of coliform and faecal Streptococcus in Ago-Iwoye well water. Nig. J. Sci., 34: 323-329.
Osungbaro, T.O., 2009.
Physical and nutritive properties of fermented cereal foods. Afr. J. Sci., 3: 23-27.Direct Link |
Ozoh, P.T.E. and A.U. Kuyanbana, 1995.
Microbiological contamination of pap akamu in Bauchi markets from water or utensils. Int. J. Environ. Health Res., 5: 311-316.CrossRef | Direct Link |
Parveen, S. and F. Hafiz, 2003.
Fermented cereal from indigenous raw materials. Pak. J. Nutr., 2: 289-291.CrossRef | Direct Link |
Sanni, A.I., S. Sefa-Dedeh, E. Sakyi-Dawson and M. Asiedu, 2002.
Microbiological evaluation of Ghanaian maize dough co-fermented with cowpea. Int. J. Food Sci. Nutr., 53: 367-373.CrossRef | Direct Link |
Shephard, G.S., N.L. Leggott, S. Stockenstrom, N.I.M. Somdyala and W.F.O. Marasas, 2002.
Preparation of South African maize porridge: Effect on fumonisin mycotoxin level. S. Afr. J. Sci., 98: 393-396.Direct Link |
Taulo, S., A. Wetlesen, R.K. Abrahamsen, J.A. Narvhus and R. Mkakosya, 2009.
Quantification and variability of Escherichia coli
and Staphylococcus aureus
cross contamination during serving and consumption of cooked thick porridge in Lungwena rural households, Malawi. Food Control, 20: 1158-1166.Direct Link |
Torre, M., A.R. Rodriguez and F. Saura-Calixto, 1991.
Effects of dietary fiber and phytic acid on mineral availability. Food Sci. Nutr., 1: 1-22.PubMed | Direct Link |
Wacher, C., A. Canas, P.E. Cook, E. Barzana and J.D. Owens, 1993.
Sources of microorganisms in pozol, a traditional mexican fermented maize dough. World J. Microbiol. Biotechnol., 9: 269-274.CrossRef |
Willey, J.M., L.M. Sherwood and C.J. Woolverton, 2008.
Prescott, Harley and Kleins's Microbiology. 7th Edn., McGraw-Hill Higher Education, USA., ISBN: 9780071102315, Pages: 1088
Nigeria: 2010 cholera outbreaks-more than 1,500 fatalities. http://www.flutrackers.com/forum/showthread.php?t=139473.
Maize, rice and wheat: Area harvested, production quantity, yield. Food and Agriculture Organization of the United Nations, Statistics Division 2009.
Singh, V.P. and N. Sachan, 2011.
-a vital vitamin for human health: A review. Am. J. Food Technol., 6: 857-863.CrossRef |
Uddian, M.J. and M.Z. Hossain, 2008.
Predictors of infant mortality in a developing country. Asian J. Epidemiol., 1: 1-16.CrossRef | Direct Link |
Onovo, J.C. and A.O. Ogaraku, 2007.
Studies on some microorganisms associated with exposed tigernut (Cyperus esculentus
L.) milk. J. Boil. Sci., 7: 1548-1550.CrossRef | Direct Link |
Shahcheraghi, F., M. Rahbar, S.M. Zahraei, V.S. Nikbin and F. Shooraj, 2009.
Transmission of Vibrio cholera
O1 serotype inaba in a rural area of qazvin, Iran Associated with Drinking Water. Asian J. Epidemiol., 2: 66-71.CrossRef | Direct Link |
Yeboah-Manu, D., G. Kpeli, M. Akyeh and L. Bimi, 2010.
Bacteriological quality of ready-to-sell foods sold in and around University of Ghana campus. Res. J. Microbiol., 5: 130-136.
Okafor, P.N. and O.D. Omodamiro, 2006.
Assessment of chemical/phytotoxin and microbial contamination of pasta foods marketed in Nigeria. Am. J. Food Technol., 1: 190-195.CrossRef | Direct Link |
Alalade, O.A. and J.A. Adeneye, 2007.
The effect of short-term frozen storage on the chemical composition and Coliform Microflora of Wara Cheese Wara Cheese under frozen storage. Am. J. Food Technol., 2: 44-47.CrossRef | Direct Link |
Oladipo, I.C. and R.O. Omo-Adua, 2011.
Antibiotics resistance among bacteria isolated from evaporated milk. Asian J. Biol. Sci., 4: 77-83.CrossRef | Direct Link |
Chukeatirote, E., C. Chainun, A. Siengsubchart, C. Moukamnerd and P. Chantawannakul et al
Microbiological and biochemical changes in Thua nao
fermentation. Res. J. Microbiol., 5: 309-315.