Evaluation of the Nutritional and Microbiological Quality of Kunun (A Cereal Based Non-Alcoholic Beverage) in Rivers State, Nigeria
E Essien, C Monago, E Edor
biochemical analysis, kunun drinks, microbes., microbial analysis
E Essien, C Monago, E Edor. Evaluation of the Nutritional and Microbiological Quality of Kunun (A Cereal Based Non-Alcoholic Beverage) in Rivers State, Nigeria. The Internet Journal of Nutrition and Wellness. 2009 Volume 10 Number 2.
Evaluation of the nutritional and microbiological quality of laboratory processed and hawked kunun drinks (A Cereal Based Non-Alcoholic Beverage)
Food is any substance, usually composed of carbohydrates, fats, proteins and water, which can be eaten or drunk by animals including humans for nutrition or pleasure. Items considered food may be sought from plants, animals or other categories such as fungus and fermented products (Jango-cohen, 2005). In many developing Countries like Nigeria, people depend mostly on indigenous technology for food preparations especially food of plant origin. Some of these foods that originates from plant includes on alcoholic beverages made mostly from cereal grains. In addition to filling a basic human need, beverages form part of the culture of human society (Larry).
Kunun is a traditional non-alcoholic fermented beverage widely consumed in the Northern parts of Nigeria especially during the dry season (Adeyemi and Umar, 1994). Kunun is cheap and the cereals used in its preparation are widely grown throughout the savannah region of Nigeria such as Bauchi, Kano, Sokoto and Katsina States (Agoa, 1987). Kunun is consumed anytime of the day by both adult and children as breakfast drink or food complement, It is usually used as appetizer to entertain visitors in rural and urban centers and is commonly served at social gatherings Onuorah
Kunun processing is mostly done by women using simple household equipment and utensil. Depending on cereal availability, Sorghum, Maize, millet, Gunea corn or rice are commonly used for kunun preparation. According to Odunfa and Adeyeye (1985) the traditional processing of Kunu involves the steeping of grains, wet milling with spices (ginger, cloves pepper), wet sieving and partial gelatinization of the slurry, followed
by the addition of sugar and bottling. The processed Kunun is usually packed for sale either in plastic bottles or in large containers and distributed under ambient temperature or cooled in a refrigerator where available. Kunun-zaki processed from sorghum grains contains 11.6% protein, 3.3% fat, 1.9% ash and 76.8% carbohydrate and arrays of amino acid (Lichtenwalner
However, this nonalcoholic beverage is however becoming more widely accepted in several other parts of Nigeria, including Port Harcourt metropolis, owing to its refreshing qualities.
The preparation of this beverage has become technology in many homes in the rural communities and more recently in the urban areas where commercial production due to support from the government through the poverty alleviation scheme, has helped to alleviate poverty among the people.
In developing nations like Nigeria, it has not been possible to have control over the processing of hawked foods, because most of the vendors lack the adequate knowledge of food processing and handling practices. As such, there is likely to be a high risk of chemical and microbial contamination. A large number of lactic acid bacteria, coliforms, molds and yeast have been reportedly implicated in food spoilage as they use the carbohydrate content of the foods for undesirable fermentation processes (Odunfa, 1988; Ojokoh
In most Nigeria cities, the sales and consumption of this locally made beverage is high due to the high cost other non-alcoholic drinks. This drink is usually hawked in the motor parks, military barracks, school premises and market places.
This research was therefore conducted to investigate the nutritional and microbiological qualities of this hawked non-alcoholic drink called Kunun-Zaki in selected locations of Port Harcourt Metropolis, south- south Nigeria.
Materials and Methods
Hawked Kunun drinks samples were purchased from four locations in in PortHrcourt Metropolis- Rumuokoro market, Mile 1 and Mile 3 motor parks and the Army barracks in Bori camp. Five samples were purchased in each location, properly labeled and placed in plastic containers. These samples were respectively brought to the Biochemistry and Microbiology laboratory of the Biochemistry and Microbiology Departments of the University of Port Harcourt for biochemical and microbiological analysis respectively. A Kunun drink sample was also prepared in the laboratory using Millet and Guinea corn respectively. The samples were purchased from the Bori camp Mammy market.
The drink samples were also subjected to the same analysis.
Biochemical analysis carried out on the Kunun drink samples include the pH, the % ash, % moisture content, % total solid, protein, total titrable acidity, carbohydrate content and ether extract (AOAC, 1990).
Isolation of microbes associated with Kunun zaki drinks: Ten fold dilutions of each kunun samples were made using 0.1% peptone water. Appropriate dilutions were made and 0.1 mL of the diluted samples were pour plated in triplicate plates on Plate Count Agar (PCA) for viable count, Eosin Methylene Blue (EMB) for
Identification of the microbial isolates: Colonies were selected randomly, bacteria cultures were characterized and identified using various morphological and biological test such as gram stain, spore stain, motility, catalase, coagulase, indole, MR –VP, urease, citrate, Oxidase and sugar fermentation. Pure cultures of each isolate were obtained by streaking the specific colonies on suitable media and incubated appropriately; these were maintained in an agar slant in McCartney bottles. The identification of the microbial isolates was based on classification Scheme proposed by Harrigan and McCance (1976), Buchanan and Gibbson (1974) and Collin and Lyne (1984). The identification was based essentially on morphological and biochemical reactions.
Result obtained was subjected to analysis of variance using one – way ANOVA. Differences between means were separated using Duncan’s Multiple Range Test (Steel and Torrie, 1980, Duncan, 1955).
Results and Discussion
Results of the biochemical analyses of Hawked and laboratory processed kunun are shown in Table 1.
Results presented in Table 1 shows that the highest crude protein % was found in the hawked Kunun zaki samples obtained from Mile 1 market (1.98±0.01%), followed by Rumuokoro market (0.98±0.02%) while samples from Mile 3 had the lowest protein content (0.67±0.05%). The kunun drinks prepared with guinea corn had the highest protein content of 0.80±0.01% while that prepared with millet had a protein content of 0.48±0.02%. Ash content ranged from 0.42±0.10% to 1.38±1.08% in the hawked kunun samples while the laboratory prepared samples had ash contents of 1.14±0.56 and 1.09±0.05 respectively.
There was no significant difference between the Carbohydrate contents and the PH of the hawked and the laboratory prepared samples while the Total titratable acidity of samples obtained from Mile 1 Motor park/market and Bori camp army barracks were significantly higher (0.45±0.10 and 0.35±0.10% respectively) than samples obtained from Mile 3 Motor park and Rumuokoro markets (0.12±0.01 and 0.13±0.03% respectively). Total solids of the laboratory prepared samples were significantly higher than in the hawked samples (Table 1).
Six different microbes were found associated with the Hawked (marketed) Kunun in Port Harcourt metropolis while the laboratory processed samples harboured five (Table 2). These microbes include
Results in Table 3 indicate that the highest total viable count of 8.00×106 cfu/ml was recorded for samples obtained from Rumuokoro market followed by samples obtained from Mile 3 Motor park/market (7.40×106 cfu/ml), while the least mean total viable of was recorded for samples obtained from Bori camp and Mile 1 markets.
These values were however significantly lower than values recorded for the laboratory prepared kunun samples (1.60×106 cfu/ml and 1.02 ×106 cfu/ml respectively). The coliform count ranged from 2.9×106 cfu /ml to 5.8×106 cfu/ ml in the hawked samples while no coliform was found associated with the laboratory processed samples. There was no observable growth of salmonella/shigella in both the hawked and laboratory prepared samples, while the hawked samples from Mile 1 and Mile 3 Motor Park/ markets had staphylococcus counts of 3.5±0.03 and 3.1±0.01×102 cfu/ml respectively. No staphylococcuss was observed in the Bori camp, Rumuokoro and the laboratory prepared samples.
Results of the experiment indicated that the highest crude protein content was found in the hawked Kunun samples compared to the laboratory prepared samples. Reasons for this might have been as a result of some of the additives added to the processed kunun samples. However, the protein contents of these Kunun drinks were very low probably because most of it might have been loss during processing. According to Hamad and Fields (1979), much of the protein in cereals is usually located in the testa and germ which are usually sifted off during processing. The protein contents obtained in this study were lower than that observed in sorghum-based kunun drinks by Amusa and Odunbaku, (2009). This may have been due to the use of Guinea corn and millet to prepare the drinks. However, Lichtenwalner
Results obtained for total titrable acidity of the hawked samples from two locations were higher than values obtained for the laboratory prepared samples. Values obtained for the laboratory prepared samples (0.27±0.03and 0.25±0.01g/100g respectively) compared well with values obtained by Amusa and Ashaye (2009) in kunun drink which ranged between 0.21 and 0.28g/100g. High total solids content of the laboratory prepared samples compared to the hawked samples may be due to loss of slurry during the wet milling of the cereal grains.
The microbes associated with the kunun samples include
The presence of some of these organisms are not surprising as most of them are known to thrive in medium rich in fermentable substrates such as sugars which often led to the production of acids after fermentation. Odunfa and Adeyeye (1985) reported that
Some of these associated microbes have been implicated in food poisoning outbreak of some food materials (Sartory and Howard, 1992). The presence of Escherichia
The presence of coliform bacterial in the hawked kunun drinks is not unexpected since the source of water used in many parts of Port Harcourt metropolis is tap or borehole water. Coliforms as been reportedly associated with tap water popularly consumed in some towns in Nigeria (Adegoke
The presence of
This is a source of concern in Nigeria because the teaming populace relies on these drinks as alternatives to the bottled canned drinks whose price is becoming unaffordable. It is therefore suggested that kunun drinks should be properly processed to avoid microbial contamination. While treated municipal water or clean water should be used during for processing and dilution of the processed drinks to avoid contamination with enteropathogenic bacteria.
Since spices have been reported to inhibit microbial growth (Zaika