Production, Acceptability and Microbiological Evaluation of Weaning Food Formulations by M. H. Badau,a I. A. Jideani,b and I. Nkamaa a Department of Food Science and Technology, University of Maiduguri, P.M.B. 1069, Maiduguri, and b Biological Sciences Programme, Abubakar Tafawa Balewa University, P.M.B. 0248, Bauchi, Nigeria
Summary Weaning food formulations were produced from pearl millet cultivar (SOSAT C-88), cowpea and groundnut in the ratio of 70:20:10 and 5 per cent malt from six pearl millet cultivars (SOSAT C-88, ZANGO, EX-BORNO, ICMV IS 94206, GWAGWA, GB 8735) and one sorghum cultivar (ICSV III) were added to produce seven formulations plus the one without malt. Microbiological quality of eight weaning food formulations was evaluated. Twenty weaning mothers were used to determine the acceptability of gruels from the eight weaning food formulations using a nine-point hedonic scale. Addition of 5 per cent malt did not affect the microbial count of weaning food formulations. Saccharomyces cerevisiae, Klebsiella aerogenes and Aspergillus niger were found in all the weaning food formulations. Shigella and Salmonella were not encountered in this study. Addition of 5 per cent SOSAT C-88, ZANGO, EX-BORNO, ICMV-IS 94206 and GWAGWA malt improved the taste and texture of weaning food formulations. The population of micro-organisms isolated from weaning formulations was not high enough to produce effective dose. However, the need for processors of weaning foods to adopt strict hygiene practices cannot be overemphasized.
Introduction Weaning food produced by sophisticated technologies is costly and is not within the reach of rural dwellers and low income earners in the urban cities. Most families have to depend on the local material and technology for the preparation of weaning food. The alternative cheap technology for preparation of low cost weaning food is malting1 and the finished product is seldom free of micro-organisms. The incidence of diarrhoea among children that are feed with this kind of weaning food has been reported.2 Therefore, there is the need to evaluate the weaning food produced to ascertain its microbiological quality. The objectives of the study were to produce weaning food formulations with local materials and using cheap technology. And also to determine the acceptability and to identify microorganisms that were associated with the weaning food formulations.
Correspondence: M. H. Badau, Department of Food Science and Technology, University of Maiduguri, P.M.B. 1069, Maiduguri, Nigeria. E-mail
[email protected].
Materials and Methods Pearl millet cultivars and sorghum were obtained from International Research Institute for the Semi Arid Tropics (ICRISAT) experimental station at Bagauda, Kano and Lake Chad Research Institute, Maiduguri, Nigeria. Cowpea and groundnut were purchased in large quantities from Maiduguri Monday market. Sugar (sucrose) was obtained from University of Maiduguri commercial area. Culture media were obtained from recognized distributors through their agent in Nigeria. Sample preparation The cereal grains were thoroughly cleansed manually using screen and unwanted materials discarded. Broken grains as well as seeds, sand, bit of metal were removed. The cleaned grains were kept in iron cupboard at room temperature (32 2 C) until required. Experimental samples were taken using quarterly procedures of Lees.3 Preparation of weaning food ingredients Weaning food was prepared as described by Nkama, et al.,4 Livingstone, et al.,5 and AlmeidaDomeiguez, et al.6 A bulk of SOSAT C-88 was dehulled with a commercial rice steel huller (Amuda, India) to obtain about 76.5 per cent dehulled grain.4 The dehulled grain was winnowed, washed and
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soaked in tap water 3 times their weight. Lime juice extract was added to water used for soaking and pH adjusted to 3.1 to remove the pearl millet greyish colour. After soaking for 24 h, the millet was washed and subsequently roasted for 30 min at 180 C in an oven (Townson and Merie Runcorn Cheshine, WA7 1PR, England) and millet in a hammer mill (Gibbons Electric, Essex, U.K.) to pass through screen of 1 mm mesh size. Malting Six pearl millet cultivars (SOSAT C-88, ZANGO, EX-BORNO, ICMV-IS 94206, GWAGWA, GB 8735) that had good malting properties, negligible tannin content,7 had no traces of lead and cadmium8 along with one sorghum cultivar (ICSV 111) were malted as described by Morrall, et al.,9 Aniche,10 Aniche and Palmer,11 Obizoba and Atii12 and Gomez, et al.13 The grains were steeped at room temperature (32 2 C) for 12 h. The steep liquor was changed after 6 h. One air rest period of 1 h was applied after 6 h of steeping. After steeping, the grains were washed and drained. The grains were immersed in a 0.1 per cent (vol/vol) solution of a commercial bleach (parazone) containing 3.5 per cent sodium hydrochlorite diluted to 175 ml with distilled water as reported by Morall, et al.9 After sterilization, the grain was wrapped in wet pieces of cotton cloth and placed on wet jute bag. Another wet jute bag was used to cover the grains wrapped in the wet cotton cloth.12 The pearl millet grains were allowed to germinate at room temperature (32 2 C) for 12 h. During germination, small quantity of water (15 ml) was sprayed on the germinating grains using an atomizer spray and they were ‘turned’ (by moving a clean wooden rod inside the germinating grains) at the same time.10 At the end of germination, the germinated grains were dried to moisture content of 5.44 0.49 in a fan fitted oven (Gallenkamp, England) at 50 C for 24 h. The dried germinated grains were polished by removing roots and rootlets. Rootlets and shoots of the grains were separated from the kernels by robbing between the palms in a sieve (Endecotts Ltd, London, England) of 0.6 mm mesh size. The sieve allowed the rootlets and shoots to escape but retained the kernels.9,11 The fine polished malt was milled into flour with hammer mill (Gibbon Electric, Essex U.K.) to pass through 1 mm mesh screen, packed in plastic containers and stoned in iron cupboard shortly before use. Large quantity of cowpea was also soaked in tap water three times its weight by volume for 5 min to facilitate dehulling. The cowpea was dehulled with pestle and mortar. The dehulled cowpea was washed, drained and roasted for 30 min at 180 C in oven. A bulk of groundnut was dry roasted at 180 C Journal of Tropical Pediatrics
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for 30 min. After cooling, the skins were removed (blanching) by rubbing between the palms. All samples were roasted to a golden brown colour. The six polished malted pearl millet cultivars and sorghum, the dehulled soaked and roasted SOSAT C-88 and dehulled roasted cowpea were milled with hammer mill (Gibbons Electric, Essex, U.K.) into fine flour, while the roasted and blanched groundnut was milled in disc attrition premier A-1 mill (1 amp motor, Yamaha, Iwota, Japan) to fine particles. Weaning food formulations The weaning food was formulated using pearl millet and legumes in the ratio of 70:30 as described by Almeida-Dominguez, et al.6 The 100 g mix of the weaning food contained 63 g of dehulled soaked and roasted SOSAT C-88 flour, 18 g of cowpea flour, 9 g of groundnut meal, 5 g of sugar and 5 g of malt flour where applicable (Table 1). Firstly, the milled processed SOSAT C-88 flour, cowpea flour and groundnut meal were blended in a blender (Kenwood, England A 707 A, McD3 19328), followed by adding sugar and finally malt flour. The mixture was blended thoroughly until uniform distribution of particles (by visual examination) was achieved. The roasted pearl millet flour, cowpea and groundnut meal were blended with malt flour from the six pearl millet cultivars and one sorghum cultivar. This was done to produce seven formulations (with malt) and one formulation without malt, a total of eight formulations (Table 1). Sensory evaluation of weaning food gruel The gruel of the eight weaning food formulations was prepared as described by Mosha and Svanberg.1 It was served to 20 weaning mothers who were asked to rank the gruels on the basis of taste, texture, colour, aroma and overall acceptability using a point hedonic scale, where 1 ¼ ‘dislike extremely’ and 9 ¼ ‘like extremely’ as reported by Larmond.14 Weaning food gruels were served to the panellists in white and transparent glass cups and were asked to rinse their mouth with fresh room-temperature water provided, before next serving. The containers with the samples were coded and kept far apart to avoid crowding and for independent judgement. Although, the panellists were not trained but their selection was based on basic requirements of a panellist, such as availability for the entire period of evaluation, interest, willing to serve, good health (not suffering from colds), not allergic or sensitive to the products evaluated.15 Microbiological analysis The microbiological analysis of the weaning food formulations were determined as described by 167
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Table 1 Weaning food formulations Formulations Ingredient (g) Roasted SOSAT-C88 Flour Roasted Cowpea Flour Roasted Groundnut Flour Sugar Pearl malt flour SOSAT C-88 ZANGO EX-BORNO ICMV-IS 94206 GWAGWA GB 8735 Sorghum malt flour ICSV III Total
I 66.5 19.0 9.5 5.0
II 63.0 18.0 9.0 5.0
III 63.0 18.0 9.0 5.0
IV 63.0 18.0 9.0 5.0
V 63.0 18.0 9.0 5.0
VI 63.0 18.0 9.0 5.0
VII 63.0 18.0 9.0 5.0
VIII 63.0 18.0 9.0 5.0
– – – – – –
5.0 – – – – –
– 5.0 – – – –
– – 5.0 – – –
– – – 5.0 – –
– – – – 5.0 –
– – – – – 5.0
– – – – – –
–
–
–
–
–
–
–
100
100
100
100
100
100
100
Collins and Lyne,16 Harriyan and McCance,17 Nkama, et al.,18 Badau, et al.19 and Badau, et al.20–22 Preparation of samples for microbial studies Sample of the eight weaning food formulations were also placed in sterile sampling containers and stored in refrigerator prior to microbiological analysis. Preparation of culture media Culture media were prepared in accordance with the methods described by Collins and Lyne,16 Harrigan and McCance,17 Nkama, et al.,18 Badau, et al.19 Badau, et al.20–22 The culture media prepared were potato-dextose agar, czapek dox agar, nutrient agar, mannitol salt, sabouraud and dextrose agar, salmonella/shigella agar. Isolation and identification of bacteria mould, and yeast Ten grams of each of the eight weaning food formulations was suspended into 90 ml of sterile water to give 101 dilution. This was done up to the 106 dilution. Each diluent of the samples was plated out in duplicate using the pour plating technique as described by Harrigan and McCance,17 Nkama, et al.,18 Badau, et al.19 and Badau, et al.20–22 Incubation of bacteria was in an aerobic incubator for 24 and 48 h at 37 C. Plates for fungal growth were incubated at room temperature (32 2 C) for 72 h. After incubation period for bacteria and fungi, their colonies appearing on the agar plates were counted using a digital colony counter. The average colony obtained from the countable duplicate plates, were expressed as colony forming unit per gram (cfu/g). All pure cultures of bacteria, moulds and yeast were maintained on nutrients agar, and 168
5.0 100
sabouraud dextrose agar slants, respectively. These isolates were kept in the refrigerator prior to identification. The cultural characteristics of discrete colonies such as colour, shape and pigmentation of the colonies were observed and noted. It was followed by characterization of the isolates using microscopic examination for cell morphology. Microscopic examinations for detailed cell morphology and gram reaction were carried out on 24 h old bacteria culturing.17 Biochemical tests were conducted on each isolate for the tests. The isolate was inoculated in peptone water and left for 24 h at 37 C. Biochemical tests carried out on all the bacteria isolates in each sample were starch hydrolysis, catalase test and utilization of sugars. The sugars used were glucose, sucrose, mannose, mannitol, xylose, arabinose, lactose, galactose, starch, maltose and fructose. Voges Proskauer, nitrate reduction, indole and motility tests were carried out using the methods described by Collins and Lyne,16 Harrigan and McCance.17 Results obtained from these tests were compared with literature standards using diagnostic tables showing the biochemical reactions identifying many genera and species of bacteria.23 Fungal isolates were identified based on cultural and morphological characteristics. It was prepared by taking an inoculum from the edge of an isolated colony, placing it on a slide and mounting fluid (Lactophenol cotton blue) added. This was covered with a cover slip and heated on a flame to expel air bubble. The prepared slide was mounted on a microscope and morphological characteristics and types of spores noted. The moulds were identified as reported by Gilman,24 Gaffa and Jideani,25 and Singh, et al.26 Journal of Tropical Pediatrics
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3
Mocrobial count log10 (cfu/g)
2.5
2 VIII VII 1.5 VI V 1 IV
Formulations
III
0.5 II
Micro-organisms
Mould
Staphylococus
I Yeast
Coliform
Total bacteria
0
Fig. 1. Microbial count of weaning food formulations (Formulation 1 had no malt, Formulations II, III, IV, V, VI, VII & VIII had 5% SOSAT C-88 malt, ZANGO, EX-BORNO, ICMV-IS 94206, GWAGWA, GB 8735 and sorghum (ICSV III), respectively). Statistical analysis Statistical analysis was carried out as described by Gomez and Gomez,27 Mead, et al.28 and with computer programme, statistics, version 4.1 USA. Analysis of variance was used to determine differences among microbial count and sensory scores of weaning food gruels. The means were separated using Duncan multiple range test.27 Results and Discussion The microbiology of weaning food formulations The microbial count log10 (cfu/g) of the various weaning food formulations mix are presented in Fig. 1. The total bacterial count of the weaning food formulations ranged from 2.48 to 2.57 log10 (cfu/g), coliform from 1.67 to 2.15, yeast from 1.20 to 1.59, staphylococcal from 1.48 to 1.59 and mould from 1.18 to 1.54. The addition of malt had no effect on the total bacterial count. The distribution of micro-organisms and their percentage frequency of occurrence in the weaning food formulations are shown in Table 2. The Journal of Tropical Pediatrics
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predominant micro-organisms encountered in weaning food formulations I was Rhizopus arrhizus. Proteus vulgaris and Rhizopus arrhizus occurred more frequently in weaning food formulation II. Bacillus coagulans, Rhizopus arrhizus, Staphylococcus aureus, Bacillus subtilis and Staphylococcus aureus occurred most frequently in weaning food formulations II, IV, V, VI, VII and VIII, respectively. Saccharomyces cerevisiae, Staphylococcus aureus, Klebsiella aerogenes and Aspergillus niger were widely distributed. It occurred in all the weaning food formulations at relatively lower frequency in most cases. Rhizopus arrhizus was distributed in almost all the weaning food formulations (except formulation I) and occurred at higher frequencies. Contamination of weaning food many occur as a result of poor hygiene of the personnel, the equipment and air of the environment where the weaning food preparation takes place. The preliminary processes such as roasting at high temperature eliminate microorganisms. The presence of micro-organisms may be due to the sugar and other ingredients added. Saccharomyces cerevisiae, Klebsiella aerogenes and Aspergillus niger were found in all the weaning food 169
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Table 2 Distribution of micro-organisms and their percentage frequency of occurrence in weaning food formulations1 Weaning food formulations2 Microorganism Saccharomyces cerevisiae Candida utilis Staphylococcus aureus Bacillus subtilis Proteus vulgaris Lactobacillus delbruekii Klebsiella aerogenes Candida tropicalis Streptococcus lactis Bacillus coagulans Bacillus cereus Candida albicans Escherichia coli Aspergillus niger Rhizopus arrhizus Aspergillus fumigatus Aspergillus nidulans Aspergillus versicolor
I 45.83 37.50 33.33 50.00 54.17 33.33 4.17 – – – – – – 12.50 58.33 – 20.83 –
II 41.67 50.00 50.00 – 54.17 – 4.17 33.33 37.50 45.83 – – – 12.50 54.17 20.83 – –
III 50.00 33.33 33.33 45.83 – – 12.50 – 33.33 54.17 41.67 – – 33.33 45.83 – 25.00 –
IV 37.50 – 50.00 – – – 8.33 41.67 50.00 58.33 54.17 – – 25.00 45.83 29.17 – –
V 45.83 33.33 37.50 – – – 4.17 33.33 45.83 33.33 – – – 33.33 54.17 – 29.17 –
VI 33.33 – 50.00 45.83 – 33.33 8.33 33.33 – 41.67 – 29.17 – 25.00 – 33.33 29.17 –
VII 29.17 – 45.83 62.50 – 33.33 12.50 41.67 50.00 – – 33.33 4.17 12.50 54.17 20.83 – –
VIII 20.83 – 54.17 – – – 8.33 37.50 16.67 33.33 12.50 33.33 4.17 25.00 12.50 29.17 – 33.33
– ¼ nil. 1 Frequency calculation was based on percentage occurrence in plated materials. 2 Formulation I had no malt, while formulations II, III, IV, V, VI, VII and VIII had, 5 per cent SOSAT-C88 malt, ZANGO, EX-BORNO, ICMV-IS 94206, GWAGWA, GB 8735, and Sorghum, respectively.
formulations. Shigella and Salmonella spp. were not encountered in the weaning foods. Gram-positive spore-forming rods isolated from weaning food were Bacillus cereus, Bacillus subtilis and Bacillus coagulans, while gram positive none spore forming rods was Lactobacillus delbruekii. Gram negative rods isolated were Escherichia coli, Klebsiella aerogenes and Proteus vulgaris. Staphylococcus aureus and Streptococcus lactis were the gram positive cocci isolated in the weaning food formulations. The moulds encountered in the weaning foods were Aspergillus fumigatus, A. niger, A. versicolour and Rhizopus arrhizus and yeasts isolated were Saccharomyces cerevisisae, Candida utilis, Candida tropicalis and Candida albicans. Aspergillus versicolour is commonly isolated as opportunistic pathogens.29 Saccharomyces cerevisiae has been implicated in food spoilage due to its fermentative ability, osmophilic nature, tolerance of acid, tolerance of alcohol and ability to grow at low temperature.30 Microorganisms that appeared in all the weaning food formulations were Saccharomyces cerevisiae, Staphylococcus aureus, Klebsiella aerogenes and Aspergillus niger. The predominating micro-organism in the weaning food formulations were Rhizopus arrhizus, Bacillus coagulans, Rhizopus arrhizus, Stapylococcus aureus, Bacilus subtilis and Staphylococcus aureus in formulations I, III, IV, V, VI and VIII respectively. Proteus vulgaris and Rhizopus arrhizus are the 170
predominating micro-organisms in formulation II. These were the likely micro-organisms to cause food spoilage or food poisoning or both if favourable conditions are provided for their growth. The populations of these micro-organisms were low in the weaning food formulations and therefore could not produce effective dose. Therefore the weaning food formulations were safe for consumption. Acceptability of weaning food formulations The sensory attributes of weaning food from mixtures of dehulled, soaked and roasted pearl millet (SOSAT C-88), cowpea and groundnut as affected by addition of malt from various pearl millet cultivars and sorghum are presented in Table 3. The aroma, colour and overall acceptability of all the weaning food gruels were not affected by the addition of malt. However, the taste of weaning food gruels that had 5 per cent SOSAT C-88 malt, ZANGO, EX-BORNO, ICMV-IS 94206 and sorghum differ from the control (Without malt) significantly ( p 5 0.05). Similarly, the texture of weaning foods that had 5 per cent malt from SOSAT C-88, ZANGO, EX-BORNO, ICMV IS 94206 were significantly preferred ( p 5 0.05). Addition of 5 per cent malt from various grains to the weaning food formulation did not change the aroma, colour and overall acceptability. However, it affected the taste and texture of gruels Journal of Tropical Pediatrics
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Table 3 The sensory quality of weaning food as affected by malt from sorghum and pearl millet cultivars1 Sensory scores Weaning food Formulation I Formulation II Formulation III Formulation IV Formulation V Formulation VI Formulation VII Formulation VIII
Aroma 6.12 7.27 6.96 6.73 7.08 6.62 6.50 6.69
Colour 6.77 7.15 7.00 7.23 6.77 6.92 6.89 7.15
Overall acceptability 6.15 7.19 7.08 6.92 7.00 6.65 6.54 6.27
Taste 5.92b 6.77a 7.00a 6.54ab 6.85a 6.31ab 5.92b 6.23ab
Texture 6.3c 7.27a 7.39a 7.23ab 7.23ab 6.85abc 6.50bc 6.46c
1
Mean of triplicate determination. Means within each column not followed by the same superscripts are significant ( p 5 0.05) different. Formulation I had no malt, while formulations II, III, IV, V, VI, VII and VIII had, 5 per cent SOSAT-C88 malt, ZANGO, EX-BORNO, ICMV-IS 94206, GWAGWA, GB 8735, and Sorghum, respectively. abc
of the weaning food formulations. Addition of the malt had a positive effect on the taste and texture of the gruels of the weaning food formulations. This could be attributed to the action of various enzymes from the malt. The principals of which are a- and b-amylases on the starchy structures of pearl millet grain, cowpea and groundnut used for preparing the weaning food. The action of the enzymes could have probably resulted in producing reducing sugars which increased the sweetness of the gruels and reduced the particle size of the ingredients resulting in smooth product. Conclusions Addition of 5 per cent malt did not affect the microbial count of weaning food. Saccharomyces cerevisiae, Klebsiella aerogenes and Aspergillus niger were found in all the weaning food formulations. Shigella and Salmonella were not encountered in this study. Addition of 5 per cent SOSAT C-88, ZANGO, EXBORNO and ICMV-IS 94206 malt improved the taste and texture of weaning foods. The population of micro-organisms was not high enough to produce an effective dose. However, the need for processing of weaning foods to adopt strict hygiene practices cannot be over emphasized. References 1. Mosha AC, Svanberg U. Preparation of weaning foods with high nutrient density using flour of germinated cereals. Food Nutrit Bull 1983; 5: 1014. 2. Appropriate Health Resources and Technologies Action Group (AHRTAG) Ltd., London, UK. (1990) Dialogue on Diarrhoea. In: The International Newsletter on the control of Diarrhoeal Diseases. 3. Lees R. In: Food Analysis: Analytical and Quality Methods for the Food Manufacturer and Buyer. 3rd edn. Leonard Hill Books, London. Journal of Tropical Pediatrics
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4. Nkama I, Dagwanna FN, Ndahi WB. Production, proximate composition and consumer acceptability of weaning foods from mixtures of pearl millet, cowpea and groundnut. J Arid Agric 2001; 11: 165–69. 5. Livingstone AS, Feng JJ. Malleshi NG. Development and nutritional quality evaluation of weaning foods based on malted popped and roller dried wheat and chickpea. J Food Sci Technol India 1993; 28: 35–43. 6. Almieda-Dominguez HD, Serna-Saldivar SO, Gomez MH, Rooney LW. Production and nutritional value of weaning foods from mixtures of pearl millet and cowpeas. Cereal Chem 1993; 70: 14–8. 7. Badau MH, Nkama I, Ajalla CO. Physicochemical characteristics of pearl millet grown in Northern Nigeria. Int J Food Prop 2002; 5: 37–47. 8. Badau MH, Nkama I, Jideani IA. Phytic acid content and hydrochloric acid extractability of minerals in pearl millet as affected by germination time and cultivar. Food Chem 2005; 92: 425–35. 9. Morall P, Boyd HK, Taylor RNT. Effect of germination time, temperature and moisture on malting sorghum. J Inst Brewing 1986; 92: 439–45. 10. Aniche GN. Studies on the effect of germination time on the malting qualities of two maize varieties. Proc Biochem 1989; 183–86. 11. Aniche GN, Palmer GA. Development of amylolytic activities in sorghum and barley malt. J Inst Brewing 1990; 96: 377–79. 12. Obizoba IC, Atii JV. Evaluation of the effect of processing techniques on the nutrient and antinutrient contents of pearl millet (Pennisetum glaucum) seeds. Plant Food Human Nutrit 1994; 45: 23–34. 13. Gomez MI, Obliana AB, Martin DF, Madzavamuse M, Monyo ES. Manual of Laboratory Procedures for Quality Evaluation of Sorghum and Pearl Millet. Technical Manual No. 2 ICRISAT, Pantecheru, Andhra Pradesh, India 1997; 502: 324. 14. Larmond E. Laboratory methods for sensory evaluation of food. Canadian Government Publishing Centre, Ottawa, Canada. 15. Penfield MP, Campbell AM. Experimental Food Sciences. 3rd edn. Academic Press, Inc., New York. 171
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16. Collins CH, Lyne PM. Microbiological Methods. Laboratory Technique Series. University Park Press, Baltimore. 17. Harrigan WF, McCance ME. Laboratory Methods in Food and Dairy Microbiology. Academic Press, London. 18. Nkama I, Badau MH, Collins EK, Mian W, Igene JO, Negbenegor CA. Microflora of some dried spices and condiments sold in Maiduguri, Nigeria. J Food Sci Technol-India 1994; 31: 420–22. 19. Badau, MH, Adeniran AM, Nkama I, Baba SS. Bacteriological quality of fresh meat sold in Maiduguri Market, Nigeria. J Arid Agric 1999; 9: 133–41. 20. Badau MH, Imhoede OL, Nkama I. Production, acceptability and bacteriological quality of kunun zaki in Maiduguri metropolis. Nigerian J Basic Appl Sci 2001; 10: 67–82. 21. Badau MH, Salami GO, Kasum AL. Microbiology assay of ingredients, contact surfaces and stages in akara processing at three locations in Maiduguri, Nigeria. Agro-Sci: J Trop Agric Food, Environ Exten 2001; 2: 42–9. 22. Badau MH, Adeniran AM, Nkama, I. Fungi associated with various fresh meat sold in Maiduguri
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